DE102017010537A1 - Air pre-filter - Google Patents

Abstract

An air pre-filter (9) for separating particles of air to provide a clean air flow comprises a housing (10) having an inlet (13) and an outlet (14) for air flow in a flow path (12) through the housing. Elements (15) are arranged to create a swirl of rotating air to move through the housing, while particles contained in the air are displaced by centrifugal forces towards the outer boundary of the flow path. The housing includes a double wall construction (17) having an inner wall (18) defining a central space (19) for the passage of clean air to the exit (14) and an outer wall (20) which together with the inner wall has an outer wall Environmental space defined (21), which receives a vortex portion (22) of air, which is loaded with particles. NACA nozzles (25) are disposed on an outer side (24) of the inner wall (18) for directing air from the outer ambient space (21) into the central space (19).

Description

TECHNICAL FIELD OF THE INVENTION

• • ein Gehäuse mit Innenwänden, die einen Strömungsweg definieren, der sich von einem Eintritt zu einem Austritt des Gehäuses erstreckt,
• • Elemente, die in der Region des Gehäuseeintritts angeordnet und dazu konfiguriert sind, Luft, die an dem Gehäuse ankommt, so dass ein Wirbel von sich drehender Luft erzeugt wird, um sich in dem Strömungsweg zu bewegen, zu dem Gehäuseaustritt hin zu leiten, während Schmutz, der in der Luft enthalten ist, durch Fliehkräfte zu der äußeren Abgrenzung des Strömungswegs hin verdrängt wird,
• • eine Doppelwandkonstruktion in einem stromabwärtigen Teil des Gehäuses mit einer Innenwand, die einen zentralen Raum zum Durchtritt von sauberer, schmutzfreier Luft zu dem Gehäuseaustritt hin definiert, und einer Außenwand, die eine Verlängerung der Innenwände, die den Strömungsweg definieren, stromaufwärts der Doppelwandkonstruktion ist und die zusammen mit der Innenwand einen äußeren Umgebungsraum definiert, der dazu konfiguriert ist, einen Wirbelteil von Luft, die mit Schmutz belastet ist, aufzunehmen, der von dem zentralen Teil der Luftströmung getrennt ist, und
• • ein Mittel, das dazu konfiguriert ist, Schmutz aus dem Gehäuse zu entfernen, indem es diesen aus dem äußeren Umgebungsraum entfernt.

The present invention relates to an air pre-filter for separating particulate soil heavier than air from contaminated air to provide a clean air flow, the pre-filter comprising:

• A housing having inner walls defining a flow path extending from an entrance to an exit of the housing,
• Elements disposed in the region of the housing entrance and configured to conduct air arriving at the housing such that a swirl of rotating air is generated to move in the flow path to lead to the housing exit while Dirt contained in the air, displaced by centrifugal forces towards the outer boundary of the flow path,
• A double-walled construction in a downstream part of the housing having an inner wall defining a central space for the passage of clean, dirt-free air towards the housing exit and an outer wall which is an extension of the inner walls defining the flowpath upstream of the double-walled construction and which together with the inner wall defines an outer ambient space configured to receive a swirl portion of air contaminated with dirt separated from the central portion of the airflow, and
• An agent configured to remove debris from the housing by removing it from the outside environment.

The invention is not limited to any particular use of an air prefilter having these features, but may be arranged in air distribution systems of various types in which it is important to maintain a clean air flow at a location downstream of the prefilter. Such an air pre-filter can be used, for example, in ventilation systems and in an air intake pipe to an internal combustion engine, possibly, but not necessarily located in a motor vehicle for removing particles from the air to be mixed with a fuel before it on the engine and the Cylinders thereof arrives, be arranged.

Accordingly, in a prefilter of this type, which is a centrifugal particle separator, the air is caused to swirl, so that the dust in the air entering the prefilter housing is pushed out to the outside of the vortex and the air in the inner area of the vortex accordingly Particles released closer to the outlet of the housing, so that the air flow entering the central space of the double wall construction will be clean and the outer part of the vortex entering the outer environment space will contain the dirt that to be separated from the air flow. The debris is then to be removed from the housing of the prefilter by removing it from that outer ambient space while preventing parts of it from moving back and entering the airflow in the central space. This has heretofore been achieved by connecting the outer ambient space to an ejector.

STATE OF THE ART

US 2014/0260129 A1 describes a prefilter with a discharge device for removing dirt from an air pre-filter. However, although the connection of an air prefilter to a jetting device results in a more efficient function of the means for removing particles from the air pre-filter, there are a number of disadvantages to the use of such soil removing agent.

In the case of an air pre-filter disposed in the air intake pipe to an internal combustion engine of a motor vehicle, the exhaust device is normally connected to the exhaust pipe of the vehicle to obtain an air flow from the pre-filter to the exhaust pipe, so that the dust from the intake air pre-filter to the Off-gas ducts and back to the outside environment is transferred. Achieving the implementation of such a conventional ejection device can be rather complicated and therefore expensive. Furthermore, such an ejector will increase the air flow upstream of the air pre-filter, which may cause unpleasant vibrations and other disturbing noises. The limitation in the exhaust system will also become higher with an ejector and cause higher fuel consumption.

BRIEF SUMMARY OF THE INVENTION

The object of the present invention is to provide an air pre-filter of the type defined in the introduction, which is improved in at least one aspect with respect to such already known air pre-filters.

This object is achieved according to the invention by providing such an air prefilter with the features listed in the characterizing part of the attached patent claim 1.

Therefore, NACA nozzles are placed on the outside of the inner wall of the double wall construction with inlet openings in the outer surrounding space and outlet openings in the central space and aligned so that air in the innermost part of the outer surrounding space is directed into the central space to flow to the housing outlet , As a result, air entering the outer peripheral space of the double-wall construction will be discharged from this space by an ejector type of suction while leaving the dirt in the outer ambient space, because a very small amount of energy is required to extract the air from the outer space outer environment space is required by such NACA-Hutzen and this energy will not be sufficient for transporting the dirt with the air through these Hutzen. Therefore, the NACA nozzles enable airflow from the outer ambient space to the main system airflow in the central space toward the housing exit. Furthermore, such NACA nozzles will not affect the behavior of the outer vortex, and thereby the centrifugal forces of the particles in the outer vortex, so that clean air is drawn from this vortex and directed back into the main airflow. This means that particles will remain in their orbit generated by the vortex, allowing them to be removed from the housing without any requirement for connection of a conventional ejector to the outside ambient space.

According to one embodiment of the invention, the NACA nozzles are arranged so that the inlet openings are aligned in a line with the intended air movement direction in a swirl part arriving at the NACA nozzle. Such an arrangement of the NACA-Hutzen is favorable for an efficient removal of air from the outer environment space of the double-wall construction, while the dirt is left inside this space.

According to another embodiment of the invention, the inner wall is provided with NACA stems at different depths into the outer surrounding space, as seen in the direction of extension of the flow path, and the inlet openings of the NACA stems are configured to angle with respect to to form a general extent of the flow path through the housing, which increases with the depth of the digits. This results in an adjustment of the angle to the change of direction of the air in the swirl part in the outer surrounding space as it penetrates deeper into the room to efficiently transfer air that is free of dirt from that room to the central room and to to achieve the exit of the air pre-filter.

According to another embodiment of the invention, the outer ambient space is provided with a downstream bottom interconnecting the inner wall and the outer wall of the double-wall construction. The arrangement of such a floor allows the accumulation of debris separated from the air on this floor and according to another embodiment of the invention, the debris removal means is disposed in this floor.

According to another embodiment of the invention, the air pre-filter is configured to be located in use so that the flow path extends from an inlet to an outlet that is lower than the inlet, and according to another embodiment of the invention, the soil removal means in FIG arranged on the floor and includes a drain valve disposed in this floor to open when a predetermined total weight of the dirt rests on the ground. This type of depletion of debris separated from the airflow from the air pre-filter will be highly efficient without the disadvantages of having an ejector connected to the outer ambient space of the air pre-filter to achieve depletion of the debris.

According to another embodiment of the invention, the distance separating the inner wall and the outer wall of the double wall construction is 20% -50%, 20% -40% or 20% -30% of the radius of the central space. Such a relationship of the cross section of the central space with respect to the cross section of the space defined by the inner walls of the housing will be able to ensure that the air entering directly into the central space of the double wall construction will not contain any dirt and the contaminated air entering the outer ambient space is efficiently drawn through the NACA nozzles into the airflow in the central space while leaving the dirt inside the outer ambient space.

The invention also relates to an air distribution system according to the appended independent claim, which is directed to such an air distribution system. The advantages thereof and the embodiments of such an air distribution system defined in the dependent claims will be clear from the above discussion of the air prefilter according to the invention.

The invention also relates to the use of an air pre-filter and a motor vehicle, which are defined in the corresponding appended claims.

Further advantageous features and advantages of the present invention will become apparent from the following description below.

list of figures

With reference to the appended drawings, below follows a specific description of an embodiment of the invention given as an example.

• 1 ist eine schematische Ansicht, die darstellt, wie ein erfindungsgemäßes Luftverteilungssystem, das einen erfindungsgemäßen Luftvorfilter enthält, in einem Kraftfahrzeug zum Bereitstellen von Luft für einen Verbrennungsmotor angeordnet werden kann,
• 2 ist eine partiell geschnittene schematische Ansicht eines Luftvorfilters gemäß einer Ausführungsform der Erfindung und
• 3 ist eine vergrößerte Ansicht, die die Anordnung der NACA-Hutzen in einem Luftvorfilter gemäß 2 darstellt.

In the drawings:

• 1 Figure 3 is a schematic view illustrating how an air distribution system incorporating an air pre-filter according to the present invention may be mounted in a motor vehicle for providing air to an internal combustion engine;
• 2 is a partially sectioned schematic view of an air pre-filter according to an embodiment of the invention and
• 3 is an enlarged view showing the arrangement of the NACA-Hutzen in an air pre-filter according to 2 represents.

DETAILED DESCRIPTION OF AN EMBODIMENT OF THE INVENTION

1 schematically illustrates the general structure of an air distribution system in which an inventive air pre-filter may be included. The air distribution system is for supplying air to an internal combustion engine 1 of a motor vehicle 2 arranged and has a turbocharger 3 and a compressor 4 in an intake manifold 5 is arranged to the engine, and a turbine 6 in the exhaust pipe 7 from the engine to the compressor 4 through a wave 8th which drives the compressor by the flow of exhaust gases impinging on the turbine blades. An air pre-filter 9 in the form of a centrifugal particle separator of the type to which the air filter of the present invention belongs is in the intake manifold 5 arranged to remove dirt in the form of particles from the air flow before it reaches the engine.

An air pre-filter 9 according to an embodiment of the invention for separating particulate dirt, which is heavier than air, from contaminated air to provide a clean air flow, is disclosed in US Pat 2 shown. The air pre-filter has a housing 10 with interior walls 11 on that a flow path 12 Define yourself from an entry 13 to an exit 14 of the housing extends. Elements in the form of vanes 15 are arranged in the region of the housing inlet and configured to air, which arrives at the housing, so that a vortex 16 is generated by rotating air to get in the flow path 12 to move, to the housing outlet 14 to direct, while dirt contained in the air is displaced by centrifugal forces to the outer boundary of the flow path, ie closer to the inner walls 11 when it moves through the air pre-filter housing.

A double wall construction 17 is disposed in a downstream part of the housing, here immediately upstream of the outlet 14 , with an interior wall 18 that have a central space 19 for the passage of clean, dirt-free air to the housing outlet 14 down, and an outer wall 20 which is an extension of the interior walls 11 that the flow path 12 define upstream of the double wall construction 17 is. The inner wall 18 and the outer wall 20 together define an outer environment space 21 which is configured to a vertebral part 22 to absorb air contaminated by dirt from the central part 23 of essentially clean, dirt-free air entering the central space 19 entrance, is separated.

The outside 24 the inner wall 18 The double wall construction is with NACA-Hutzen 25 provided, the inlet openings 26 in the outer environment space 21 and outlet openings 27 in the central room 19 exhibit. These NACA-Hutzen are arranged so that the entrance openings 26 in a line with the intended air movement direction in the swirl part 22 , which arrives at the NACA-Hutzen, are aligned. This means that NACA-Hutzen, which is deeper in the outer environment 21 located, as seen in the direction of extension of the flow path, with the inlet openings 26 of which a larger angle with respect to a general extent of the flow path through the housing than NACA-Hutzen, which is closer to the upstream edge 28 the inner wall 18 to form.

The general function of such NACA-Hutzen is well known, which is the reason for their use, for example, on engine covers of sports cars, and will now be with reference to 3 explained. The air of the vertebral part 22 in the outer environment 21 the double wall construction 17 enters, becomes the NACA-Hutzen 25 pulled and through these hoods in the central room 19 sucked, as by the arrows 29 and because of the very low energy required for this, the dirt inside the outer environment becomes dropped to a floor 30 leave it, which connects the inner wall and the outer wall of the double-wall construction with each other. Air, the wall sections 31 achieved that the NACA-Hutzen 25 Defining is thereby influenced by vortexes 32 to cause themselves along these wall sections 31 to the entrance opening 26 towards the NACA scoop 25 move where it is sucked into the NACA scoop to control the flow of air in the central space 19 to reach.

A drain valve 33 is on the ground 30 and will open when a predetermined total weight of soil rests on the ground to ensure reliable removal of the debris from the air pre-filter and to maintain the amount of debris accumulated inside the air pre-filter at an acceptably low level ,

The invention, of course, is in no way limited to the embodiment described above, as many possibilities for modification thereof will be apparent to one of ordinary skill in the art without departing from the scope of the invention as defined in the appended claims.

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 2014/0260129 A1 [0004]

Claims (13)

An air pre-filter for separating particulate dirt heavier than air from contaminated air to provide a clean air flow, the pre-filter comprising: a housing (10) having interior walls (11) defining a flow path (12); extending from an inlet (13) to an outlet (14) of the housing, elements (15) disposed in the region of the housing inlet and configured to receive air arriving at the housing (10) Swirl (16) is generated by rotating air to move in the flow path to lead to the housing outlet (14), while dirt contained in the air is displaced by centrifugal forces towards the outer boundary of the flow path • a double wall construction (17) in a downstream portion of the housing having an interior wall (18) defining a central space (19) for the passage of clean, debris free air to the housing exit (14) and an outer wall (20) defining an extension of the inner walls (11) defining the flow path (12) upstream of the double wall construction and defining, together with the inner wall (18), an outer ambient space (21) configured thereto is to receive a swirl part (22) of air contaminated with dirt separated from the central part (23) of the air flow, and • a means (3) configured to remove dirt from the housing in that it is removed from the outer surrounding space (21), characterized in that NACA stems (25) are formed on an outer side (24) of the inner wall (18) with inlet openings (26) in the outer surrounding space (21) and outlet openings (27 ) are arranged in the central space (19) and oriented so that air in the innermost portion of the outer ambient space (21) is directed into the central space (19) to flow to the housing outlet (14). Prefilter after Claim 1 characterized in that the NACA stems (25) are arranged so that the inlet openings (26) are aligned in a line with the intended air movement direction in a swirl part (22) which arrives at the NACA stub (25). Prefilter after Claim 1 or 2 characterized in that the inner wall (18) is provided with NACA stems (25) at different depths in the outer surrounding space (21), as seen in the direction of extension of the flow path (14), and that the inlet openings (14) 26) of the NACA nozzle are configured to form an angle with respect to a general extent of the flow path (12) through the housing (10) that increases with the depth of the locations. Pre-filter according to one of the preceding claims, characterized in that the outer surrounding space (21) is provided with a downstream bottom (30) interconnecting the inner wall (18) and the outer wall (20) of the double wall construction (17). Prefilter after Claim 4 characterized in that the soil removal means (33) is disposed in the floor (30). Pre-filter according to one of the preceding claims, characterized in that it is configured to be arranged in use so that the flow path (12) extends from an inlet (13) to an outlet (14) lower than the inlet, extends. Prefilter after Claim 5 or 6 characterized in that the soil removal means comprises a drain valve (33) disposed in the floor (30) to open when a predetermined total weight of the soil rests on the floor Pre-filter according to one of the preceding claims, characterized in that the distance separating the inner wall (18) and the outer wall (20) of the double-wall construction (17), 20% -50%, 20% -40% or 20% -30% of the radius of the central space (19). An air distribution system comprising an air flow guide channel (5), a member (4) connected to the channel for causing an air negative pressure therein, thereby generating an air flow in the channel, and an air pre-filter (9) at one location along the length of the channel for separating particulate dirt heavier than air from contaminated air to provide a clean air flow, characterized in that the pre-filter is a prefilter according to any one of the preceding claims. Air distribution system according to Claim 9 characterized in that the duct is an air intake pipe (5) to an internal combustion engine (1) and the air pre-filter (9) is configured to remove dirt from the air before it arrives at the engine. Air distribution system according to Claim 10 , characterized in that the channel forms an air intake pipe (5) leading to an internal combustion engine (1) in a motor vehicle (2). Use of an air prefilter (9) according to one of Claims 1 - 8th in an air distribution system for supplying an internal combustion engine (1) in a motor vehicle (2) with air. Motor vehicle, characterized in that it is provided with an air distribution system according to one of Claims 9 - 11 for supplying air to an internal combustion engine (1) of the vehicle.

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