DE102015012794A1 - Air mass measuring device of an air intake tract, air filter and air intake tract - Google Patents

Abstract

An air mass measuring device (16) of an air intake tract of an internal combustion engine, in particular of a motor vehicle, an air filter and an air intake tract are described. The air mass measuring device (16) comprises at least one sensor tube section (24), in which at least one air mass sensor (26) for detecting a mass flow of the intake air (32) through the at least one sensor tube section (24) is arranged. Furthermore, the air mass measuring device (16) comprises at least one hydrocarbon trap (28) for removing hydrocarbon from the gas flowing back from the internal combustion engine, which is arranged to flow through the intake air (32) with respect to the intake air flow upstream of the at least one air mass sensor (26). The at least one hydrocarbon trap (28) has a plurality of air-conducting channels (30). At least one hydrocarbon trap (28) is formed as a grid. The air-conducting channels (30) are arranged honeycomb-shaped. The walls of the air-conducting channels (30) consist of a ceramic material suitable for capturing hydrocarbon.

Description

Technical area

The invention relates to an air mass measuring device of an air intake tract of an internal combustion engine, in particular of a motor vehicle, having at least one sensor pipe section in which at least one air mass sensor for detecting a mass flow of the intake air is arranged through the at least one sensor pipe section, and with at least one hydrocarbon pipe. A trap for removing hydrocarbon from gas flowing back from the internal combustion engine which is arranged to flow through the intake air upstream of the at least one air mass sensor with respect to the intake air flow, the at least one hydrocarbon trap having a plurality of air-conducting ducts.

Furthermore, the invention relates to an air filter with at least one air mass measuring device of an air intake tract of an internal combustion engine, in particular of a motor vehicle, with at least one sensor tube section, in which at least one air mass sensor for detecting a mass flow of the intake air through the at least one sensor tube section is arranged, and with at least one hydrocarbon trap for removing hydrocarbon from gas flowing back from the internal combustion engine, which gas is arranged to flow through the intake air upstream of the at least one air mass sensor, the at least one hydrocarbon trap having a plurality of air-conducting ducts.

In addition, the invention relates to an air intake with at least one air mass measuring device of an internal combustion engine, in particular a motor vehicle, with at least one sensor tube section, in which at least one air mass sensor for detecting a mass flow of the intake air through the at least one sensor tube section is arranged, and at least a hydrocarbon trap for removing hydrocarbon from gas flowing back from the internal combustion engine, which is arranged with respect to the intake air flow upstream of the at least one air mass sensor of the intake air, wherein the at least one hydrocarbon trap having a plurality of air-conducting channels.

State of the art

From the US 20040255911 A1 For example, an air intake system is known which comprises a hydrocarbon adsorbing member for adsorbing a recycle of hydrocarbons from a vehicle engine. The air induction system includes an air filter for filtering ambient air, a clean air duct in fluid communication with the air filter, a sensor mounted adjacent to the clean air duct, and a hydrocarbon adsorber mounted on the clean air duct for adsorbing hydrocarbon recirculation the engine. The hydrocarbon adsorber comprises an outer body having an air inlet end and an air outlet end. The body is made of hydrocarbon adsorbent material and has a structure of interconnected inner walls disposed therein and spaced from one another. The partitions are arranged so that they are limited by channels, which increase in size from radially inward to radially outward.

The invention has for its object to make an air mass measuring device, an air filter and an air intake tract of the type mentioned, in which an air flow in the region of the at least one air mass sensor improved and a deposition of hydrocarbons contained in rückströmendem gas can be improved.

Disclosure of the invention

This object is achieved in that at least one hydrocarbon trap is formed as a grid, the air-conducting channels are arranged honeycomb and the walls of the air-conducting channels made of a suitable material for capturing hydrocarbon ceramic material.

According to the invention, at least one hydrocarbon trap is combined with at least one air mass sensor in such a way that both the removal of hydrocarbons contained in the gas flowing behind and the measurement of the mass flow of the intake air by the air mass measuring device are realized. With the at least one hydrocarbon trap, hydrocarbons can be taken up from the refluxing gas, in particular adsorbed and / or absorbed. Thus, it can be prevented that backflowing hydrocarbons from the internal combustion engine can pass through the air intake tract into the environment.

The terms "upstream" and "downstream" refer to the flow direction of the intake air throughout normal operation of the internal combustion engine. The backflowing gas is the gas, which can flow back into the air intake tract, in particular during an operation stop of the internal combustion engine. In general, it can be thereby fuel vapors, in particular petrol fumes act.

At least one hydrocarbon trap is formed as a grid. The permeable areas of the grid form the air-conducting channels. At least one hydrocarbon trap may have a regular, solid structure.

The air-conducting channels are arranged honeycomb. "Honeycomb" in the sense of the invention means that the air-conducting channels are the same shape and have similar dimensions. The air-conducting channels may have the same flow cross sections, in particular diameter and profiles, and / or lengths.

In the channels, the intake air is passed. It can be specified with the channels whose flow direction, in particular on the downstream side. Through the honeycomb-shaped arrangement, a more uniform flow can be achieved over the entire areal extent transversely to the direction of flow of the intake air. Thus, an air flow in the flow field of the intake air flowing from the channels can be improved, in particular calmed. In contrast to the air intake system known from the prior art, according to the invention a more uniform flow field can be realized transversely to the flow direction.

At least one hydrocarbon trap is disposed upstream of at least one air mass sensor. In this way, the air flow of the intake air in the region of the at least one air mass sensor is improved by the air-conducting channels of the at least one hydrocarbon trap, in particular calmed. Thus, a signal quality at the at least one air mass sensor can be improved. The at least one hydrocarbon trap is additionally used as air mass sensor. An additional air mass sensor can be dispensed with.

The grid of the at least one hydrocarbon trap consists of a ceramic material which is suitable for capturing, in particular for adsorption and / or absorption, of hydrocarbon. The ceramic material has the advantage that it has a particularly smooth surface. In this way, the walls of the air-conducting channels provide a fluidically correspondingly low resistance. Furthermore, turbulences in the air flow are reduced, preferably avoided, by the correspondingly smooth surfaces of the ceramic material.

Advantageously, the ceramic material of the at least one hydrocarbon trap may contain carbon. Advantageously, the walls of the channels, in particular the entire hydrocarbon trap, may comprise or consist of a ceramic activated carbon material. With such ceramic materials hydrocarbons can be captured even better and removed from the back-flowing gas.

Advantageously, the air mass measuring device can be modular. Such a module may in particular comprise at least one sensor tube section, at least one air mass sensor contained therein and at least one hydrocarbon trap. Such modules can be easily pre-assembled and arranged accordingly in an air intake tract, in particular an air filter. A modular design also has the advantage that the module can be tested in advance and adjusted, in particular calibrated or calibrated.

Advantageously, the air-measuring device can be arranged in an air intake module. The air intake module may include a housing having at least one air inlet and at least one air outlet. At least one corresponding air cleaning device, in particular at least one air filter or the like, can be arranged in the housing. The at least one air filter may have at least one filter element. At least one filter element can be a so-called flat filter element, a so-called round filter element or a filter element that is realized in another way and is suitable for cleaning air.

Advantageously, the air mass measuring device may be part of an air filter, in particular an air filter module, an internal combustion engine of a motor vehicle. The air filter may advantageously be part of an air intake tract of the internal combustion engine. The air intake tract can serve to suck in ambient air as combustion air for the internal combustion engine. The air filter can be used to clean the intake combustion air.

However, the invention is not limited to an air filter of an air intake tract of an internal combustion engine of a motor vehicle. Rather, it can also be used in other types of air-carrying systems of motor vehicles. The invention can also be used outside the automotive industry, especially in industrial engines.

In an advantageous embodiment, the air-conducting channels can have identical cross-sections, in particular shapes and / or cross-sectional areas. In this way, one can still more uniform air flow downstream of the at least one hydrocarbon trap can be achieved.

In a further advantageous embodiment, a distance between an outlet side of the at least one hydrocarbon trap and an inlet side of the at least one air mass sensor may be smaller than a flow cross section of the sensor tube section in the region of the at least one air mass sensor. In this way, the at least one air mass sensor may be arranged in a region of the flow field downstream of the at least one hydrocarbon trap, in which a positive influence of the at least one hydrocarbon trap on the flow to improve the measurement quality at least one air mass sensor is particularly good. In addition, at such a small distance from the at least one hydrocarbon trap, there is less risk of turbulence than at a greater distance.

The outlet side of the at least one hydrocarbon trap is the side on which the intake air exits the at least one hydrocarbon trap during normal operation of the internal combustion engine. The inlet side is the corresponding opposite flow side.

In a further advantageous embodiment, at least one hydrocarbon trap can extend over the entire flow cross-section of the sensor tube section. In this way, the at least one hydrocarbon trap can overlap and cover the entire flow cross section of the sensor tube section. The intake air must inevitably flow through the at least one hydrocarbon trap.

Due to the positive flow through the grille, it is possible to ensure that no air passes the at least one hydrocarbon trap and passes into the flow region of the at least one Luftwaffe sensor, where it can lead to turbulences or disturbances in the air flow. Thus, the air flow in the region of the at least one air mass meter can be further calmed.

Furthermore, by the forced flow of at least one hydrocarbon trap, which also applies to the back-flowing gas, a deposition efficiency of hydrocarbons can be further improved.

In a further advantageous embodiment, at least one hydrocarbon trap can be flat at least on its outlet side, in particular on its outlet side and its inlet side. In this way, the flow field downstream of the at least one hydrocarbon trap can be made even more uniform.

Due to the planar arrangement, the air-conducting channels may have a correspondingly uniform, in particular the same, durchströmbare length. Furthermore, the outlet-side ends of the air-conducting channels can thus have the same distance to the at least one air mass sensor. The air flow in the region of the at least one air mass sensor can be further calmed in this way.

In a further advantageous embodiment, at least the walls of the air-conducting channels of at least one hydrocarbon trap can be cut off at least on its downstream side from a prefabricated ceramic semi-finished product by means of a forming process, in particular a tensile forming process. In this way, the corresponding edges of the walls can be made very smooth. In contrast to hydrocarbon traps, which are molded by a casting process, in particular injection molding, the material surface and edges according to the invention can be made even smoother.

To produce a hydrocarbon trap according to the invention, a semifinished product, in particular in the form of a cylinder, can be produced from the corresponding ceramic material by a forming process. In this case, channels for the corresponding air-conducting channels can be realized evenly. Subsequently, the semifinished product can be cut transversely to the longitudinal direction of the channels into lattices. The grids can be designed like a disk. The grids form corresponding hydrocarbon traps. From a semi-finished so can be cut several hydrocarbon traps.

In the forming process may advantageously be a so-called Zugumformverfahren.

Furthermore, the object is achieved in the air filter according to the invention characterized in that at least one hydrocarbon trap is formed as a grid, the air-conducting channels are arranged honeycomb-shaped and the walls of the air-conducting channels of a for trapping Hydrocarbon suitable ceramic material.

In addition, the object is achieved in the air intake according to the invention characterized in that at least one hydrocarbon trap is formed as a grid, the air-conducting channels are arranged honeycomb and the walls of the air-conducting channels consist of a suitable material for capturing hydrocarbon ceramic material.

Incidentally, the features and advantages shown in connection with the air mass measuring device according to the invention, the air filter according to the invention and the air intake tract according to the invention and their respective advantageous embodiments apply mutatis mutandis and vice versa. The individual features and advantages can, of course, be combined with one another, whereby further advantageous effects can be achieved that go beyond the sum of the individual effects.

Brief description of the drawings

Further advantages, features and details of the invention will become apparent from the following description, are explained in more detail in the embodiments of the invention with reference to the drawing. The person skilled in the art will expediently also individually consider the features disclosed in the drawing, the description and the claims in combination and combine these into meaningful further combinations.

It show schematically

1 a section of an air intake module of an internal combustion engine with an air mass measuring device having an air mass sensor and a hydrocarbon trap;

2 a plan view of a hydrocarbon trap, which corresponds to that in the Luftansaugmodul from the 1 is similar.

In the figures, the same components are provided with the same reference numerals.

Embodiment (s) of the invention

In the 1 is an air intake module 10 an internal combustion engine, not shown, of a motor vehicle shown in a section. The air intake module 10 is part of an air intake tract of the internal combustion engine. With the air intake module 10 is sucked from the environment sucked air and determines the air mass flow.

The air intake module 10 includes a housing 12 in which an air filter element 14 is arranged. Furthermore, the air intake module comprises 10 an air mass measuring device 16 , which on the clean air side downstream of the air filter element 14 is arranged.

The housing 12 comprises a housing base 18 , in the 1 below, which with a housing hood 20 , in 1 above, is closed. The housing body 18 has one in the cut in the 1 invisible air intake for ambient air and a recess for the air filter element 14 on the housing cover 20 facing side. In the installation opening is the air filter element 14 inserted and between the housing body 18 and the housing cover 20 sealed. The air filter element 14 is designed as a so-called flat filter element.

The housing cover 20 also has an air outlet 22 , which is connected via an air line, not shown, of the air intake tract with the internal combustion engine. The air filter element 14 is so in the housing 12 arranged that there is the air inlet from the air outlet 22 separates.

The air outlet 22 is on a sensor pipe section 24 the air mass measuring device 16 realized. The sensor pipe section 24 is exemplified as a circular cylindrical tube. The sensor pipe section 24 is an example of one piece with the housing cover 20 connected. The sensor pipe section 24 leads laterally out of the housing cover 20 out. Its longitudinal axis runs approximately parallel to the downstream side of the air filter element 14 , So approximately perpendicular to a mean flow direction of the sucked air through the air filter element 14 ,

On the air filter element 14 opposite side leads an air mass sensor 26 through the peripheral wall of the sensor tube section 24 something over the middle protruding into its interior.

On the inlet end of the sensor tube section 24 which is the air outlet 22 is a grid-like hydrocarbon trap 28 the air mass measuring device 16 arranged. The hydrocarbon trap 28 serves the removal of hydrocarbon from gases, such as gasoline vapors, for example, in an operation stop from the internal combustion engine back into the air intake tract 10 can flow.

The hydrocarbon trap 28 has about the shape of a round disc. The downstream exit side of the hydrocarbon trap 28 , which the air mass sensor 26 is facing, is just. Likewise, the opposite entrance side is flat.

The hydrocarbon trap 28 has a variety of continuous air-conducting channels 30 on each of which is from the inlet side of the hydrocarbon trap 28 extend to the exit side. The longitudinal axes of the channels 30 run parallel to each other. The channels 30 are identical in their cross-section, ie their profile and their diameters. The channels 30 are evenly arranged honeycomb.

The hydrocarbon trap 28 overlaps the inlet side of the sensor tube section 24 completely, so that during normal operation of the internal combustion engine from the intake air and, for example, in an operation stop by the flowing back gases is inevitably flowed through.

A distance between the exit side of the hydrocarbon trap 28 and the air mass sensor 26 is smaller than a diameter of the sensor tube section 24 in the area of the air mass sensor 26 , The hydrocarbon trap 28 is therefore located in the immediate vicinity of the air mass sensor 26 ,

The hydrocarbon trap 28 and with it the walls of the channels 30 are made of ceramic material containing activated carbon. The surfaces of the walls of the channels 30 and their inlet-side and outlet-side edges are extremely smooth. In this way, turbulences in the intake air flowing through are avoided.

For the preparation of the hydrocarbon trap 28 is made of the ceramic material with activated carbon, for example by a Zugumformverfahren a semi-finished product in the form of a cylinder having parallel channels, which later the air-conducting channels 30 form. Subsequently, the cylinder is sliced according to perpendicular to the longitudinal directions of the channels. Each disc forms a hydrocarbon trap 28 , By cutting the edges of the walls of the channels 30 extremely smooth. The hydrocarbon traps 28 are then attached to the corresponding sensor tube section 24 appropriate.

During operation of the internal combustion engine, ambient air is introduced through the air inlet into the housing base body 18 sucked. The air flow in the air intake module 10 is in the 1 through arrows 32 indicated. The intake air flows through the air filter element 14 , The cleaned intake air enters the housing cover 20 , From there, the intake air first flows through the hydrocarbon trap 28 , The intake air is in the channels 30 passed and evenly distributed, leaving on the exit side of the hydrocarbon trap 28 a uniform, turbulence-free air flow field is formed.

In the air flow field is the air mass sensor 26 , With this, the mass flow of the intake air through the sensor tube section 24 detected and transmitted via signal lines, not shown, for example, to an engine control of the internal combustion engine. Because the sensor tube section 24 the only air outlet 22 forms, the detected mass flow corresponds to the mass flow of the intake air through the air intake module 10 ,

The cleaned intake air leaves the air intake module 10 through the air outlet 22 and passes via the air line to the internal combustion engine.

For example, in an operation stop loaded with hydrocarbons gasoline vapors from the engine back into the Luftansaugmodul 10 stream. The gasoline vapors must the hydrocarbon trap 28 to flow against the direction of the air flow during normal operation of the internal combustion engine. In the air-conducting channels 30 are adsorbed in gasoline-containing hydrocarbons. The refluxing gasoline vapors are freed from the hydrocarbons.

In the 2 is a hydrocarbon trap 128 according to a second embodiment shown in plan view. In contrast to the first embodiment, the hydrocarbon trap 128 square. The hydrocarbon trap 128 according to the second embodiment can be used in conjunction with a corresponding square sensor tube section.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• US 20040255911 A1 [0004]

Claims (8)

Air mass measuring device ( 16 ) an air intake tract of an internal combustion engine, in particular of a motor vehicle, with at least one sensor pipe section ( 24 ), in which at least one air mass sensor ( 26 ) for detecting a mass flow of the intake air ( 32 ) through the at least one sensor tube section ( 24 ) and at least one hydrocarbon trap ( 28 ; 128 ) for removing hydrocarbon from gas flowing back from the internal combustion engine, which with respect to the intake air flow upstream of the at least one air mass sensor ( 26 ) of the intake air ( 32 ) is arranged through which the at least one hydrocarbon trap ( 28 ; 128 ) a plurality of air-conducting channels ( 30 ), characterized in that at least one hydrocarbon trap ( 28 ; 128 ) is formed as a grid, the air-conducting channels ( 30 ) are honeycomb-shaped and the walls of the air-conducting channels ( 30 ) consist of a ceramic material suitable for capturing hydrocarbon. Air mass measuring device according to claim 1, characterized in that the air-conducting channels ( 30 ) have identical cross-sections, in particular shapes and / or cross-sectional areas. Air mass measuring device according to claim 1 or 2, characterized in that a distance between an outlet side of the at least one hydrocarbon trap ( 28 ; 128 ) and an inlet side of the at least one air mass sensor ( 26 ) is smaller than a flow cross-section of the sensor tube section ( 24 ) in the region of the at least one air mass sensor ( 26 ). Air mass measuring device according to one of the preceding claims, characterized in that at least one hydrocarbon trap ( 28 ; 128 ) over the entire flow cross-section of the sensor tube section ( 24 ). Air mass measuring device according to one of the preceding claims, characterized in that at least one hydrocarbon trap ( 28 ; 128 ) at least on its outlet side, in particular on its outlet side and its inlet side, is flat. Air mass measuring device according to one of the preceding claims, characterized in that at least the walls of the air-conducting channels ( 30 ) at least one hydrocarbon trap ( 28 ; 128 ) are cut off at least on their downstream side from a prefabricated ceramic semi-finished product by means of a forming process, in particular a tensile forming process. Air filter ( 10 ) with at least one air mass measuring device ( 16 ) of an air intake tract of an internal combustion engine, in particular of a motor vehicle, in particular according to one of the preceding claims, with at least one sensor pipe section ( 24 ), in which at least one air mass sensor ( 26 ) for detecting a mass flow of the intake air ( 32 ) through the at least one sensor tube section ( 24 ) and at least one hydrocarbon trap ( 28 ; 128 ) for removing hydrocarbon from gas flowing back from the internal combustion engine, which with respect to the intake air flow upstream of the at least one air mass sensor ( 26 ) of the intake air ( 32 ) is arranged through which the at least one hydrocarbon trap ( 28 ; 128 ) a plurality of air-conducting channels ( 30 ), characterized in that at least one hydrocarbon trap ( 28 ; 128 ) is formed as a grid, the air-conducting channels ( 30 ) are honeycomb-shaped and the walls of the air-conducting channels ( 30 ) consist of a ceramic material suitable for capturing hydrocarbon. Air intake tract with at least one air mass measuring device ( 16 ) of an internal combustion engine, in particular of a motor vehicle, in particular according to one of the preceding claims, with at least one sensor tube section ( 24 ), in which at least one air mass sensor ( 26 ) for detecting a mass flow of the intake air ( 32 ) through the at least one sensor tube section ( 24 ) and at least one hydrocarbon trap ( 28 ; 128 ) for removing hydrocarbon from gas flowing back from the internal combustion engine, which with respect to the intake air flow upstream of the at least one air mass sensor ( 26 ) of the intake air ( 32 ) is arranged through which the at least one hydrocarbon trap ( 28 ; 128 ) a plurality of air-conducting channels ( 30 ), characterized in that at least one hydrocarbon trap ( 28 ; 128 ) is formed as a grid, the air-conducting channels ( 30 ) are honeycomb-shaped and the walls of the air-conducting channels ( 30 ) consist of a ceramic material suitable for capturing hydrocarbon.

Images