Abstract:
A separating device ( 1 ), in particular for a crankcase venting device of an internal combustion engine, includes an inlet ( 25 ) supplying a fluid containing particles to be separated, a baffle plate ( 22 ) separating the particles from the fluid, several nozzles ( 21 ) oriented toward the baffle plate ( 22 ), and a pivotable flap ( 15 ) that, as a function of its pivot position, fluidically connects a first number of nozzles ( 21 ) with the inlet ( 25 ) and fluidically separates from the inlet ( 25 ) a second number of nozzles ( 21 ).

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit under 35 USC 119 of foreign patent application DE 10 2012 008 808.6 filed in Germany on May 7, 2012, and which is hereby incorporated by reference in its entirety. 
     TECHNICAL FIELD 
     The present invention concerns a separating device, in particular for a crankcase venting device of an internal combustion engine. 
     BACKGROUND OF THE INVENTION 
     In operation of an internal combustion engine, blow-by gasses are generated in the crankcase. These blow-by gasses comprise an oil-air mixture. From this mixture the oil is to be separated and collected while the air is to be supplied to an intake manifold of the internal combustion engine. 
     For example, DE 10 2009 035 742 A1 describes an oil separating device for a crankcase of an internal combustion engine. The known separating device comprises a tubular inner part and an outer part surrounding it. The outer part has a baffle wall. The gas jets existing from gas passages in the interior part impinge on this baffle wall. A spherical valve element controls the volume flow that is impinging on the baffle wall. The oil that is separated at the baffle plate is collected while the air is supplied to the intake manifold of an internal combustion engine. 
     SUMMARY OF THE INVENTION 
     It is the object of the present invention to provide an improved separating device. 
     As a solution to this object, a separating device, in particular for a crankcase venting device of an internal combustion engine, is proposed which has an inlet, a baffle plate, several nozzles and a pivotable flap. The inlet is embodied for supplying a fluid containing particles to be separated. The baffle plate is embodied for separating the particles from the fluid. The several nozzles are directed onto the baffle plate. As a function of its pivot position, the flap fluidically connects a first number of nozzles with the inlet and fluidically separates a second number of nozzles from the inlet. 
     Since, by means of pivoting of the flap, the first and second numbers of nozzles are adjustable, a simple and reliable mechanism is provided. 
     Preferably, the pivot position of the flap varies as a function of the volume stream of the fluid through the inlet. Accordingly, a uniform separation, despite varying volume flow, can be achieved. Also, a pressure loss at the nozzles can be mini-mized in this way. 
     Preferably, for the first number M of nozzles, the second number N of nozzles, and the total number K of nozzles the following applies:
 
 M+N=K  
         wherein M&gt;0, N&gt;0, K&gt;2. This holds true for any pivot position of the flap.       

     The fluid can be a liquid or a gas. The fluid is in particular a gas mixture, for example, air. The particles can be liquid particles or solid particles. For example, the particles can be embodied as oil droplets. 
     According to a further embodiment, the separating device comprises a spring which loads the flap in such a way that it counteracts an increase of a volume flow of the fluid through the inlet. In this way, it is ensured that the fluid in the first number of nozzles is sufficiently accelerated in order to ensure a reliable separation at the baffle plate. The spring can be, for example, a spiral spring or a torsion spring. As an alternative to the spring, also an actuator, for example a hydraulic or electro-magnetic actuator, could be provided which, as a function of a control unit, adjusts the pivot position of the flap. The spring can also be formed by a monolithic embodiment of the flap with an axle wherein the axle is supported so as to be secured against rotation and a restoring force is generated by an elastic defor-ma-tion of the monolithic composite of flap and axle. 
     In one embodiment, the axis of rotation of the flap is horizontal and the opening direction of the flap is oriented such that the flap for opening must be lifted against the force of gravity. The flap is thus closed by its own weight and/or it experiences by its own weight a force in the direction of the inlet. By the weight of the flap, the restoring force can thus be adjusted against the incoming flow. 
     According to a further embodiment, the nozzles are distributed on a circular segment line and face in radial direction outwardly. In this context, “radial” refers to the center point of the circular segment line inasmuch as nothing to the contrary is indicated. In this context, “circular segment line” is to be understood as any partial circle, for example, a quarter circle or semi circle, but also a complete circle. 
     According to a further embodiment, the nozzles each have the same flow cross-section and/or a varying spacing relative to each other along the circular segment line. In this way, it can be achieved that, with increasing first number of nozzles and increasing spring force as well as increasing volume flow of the fluid, the exit speed of the fluid from the first number of nozzles remains constant. Accordingly, despite a changing volume flow of the fluid, a uniform separation at the baffle plate is achieved. The nozzles can have in particular a circular, polygonal, or in particular rectangular cross-section. 
     According to a further embodiment, the flap is pivotably supported about a center point of the circular segment line and extends with its free end up to a partition between the first number and the second number of nozzles in order to seal the first number and second number of nozzles relative to each other. In one embodiment, no complete sealing action is achieved but the free end has a minimal gap relative to the partition. Accordingly, a simple mechanism results in order to seal the first number and second number of nozzles from each other. 
     According to a further embodiment, between two nozzles each a partition is provided. Accordingly, several different pivot positions of the flap result in a simply way, each having correlated therewith a different number of first and second nozzles. 
     According to a further embodiment, the nozzles are arranged such that the spacing between two nozzles each decreases in the circumferential direction with increasing spacing from the inlet. In this way, it is achieved in a simple way that the exit speed of the fluid from the first nozzles, despite increasing volume flow and increasing spring force, remains constant so that a uniform separation at the baffle plate is achieved. 
     According to a further embodiment, the nozzles each have a constant cross-section. In this way, they can be produced simply, for example, by injection molding methods. 
     According to a further embodiment, the nozzles are oriented in a plane perpendicular to the force of gravity. An outlet for discharging the separated particles is oriented relative to the force of gravity in downward direction. Accordingly, the particles are deflected by approximately 90 degrees at the baffle plate so that a high degree of separation is achieved. 
     According to a further embodiment, the nozzles are oriented in a plane perpendicular to the force of gravity. An outlet for discharging the fluid from which the particles have been separated and/or the inlet is oriented in a plane perpendicular to the force of gravity. In this way, the fluid from which the particles have been separated is deflected at the baffle plate approximately perpendicularly so that a high degree of separation is achieved. 
     Further possible implementations of the invention comprise also combinations, not explicitly mentioned, of features disclosed above or in the following with regard to the embodiments or embodiments of the separating device. In this connection, a person of skill in the art will also add or modify individual aspects as improvements or supplements of the basic form of the invention. 
     Further embodiments of the invention are subject matter of the dependent claims as well as of the embodiment of the invention described in the following. In the following, the invention will be explained in more detail with the aid of embodiments with reference to the attached Figures. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The accompanying Figures, where like reference numerals refer to identical or functionally similar elements throughout the separate views and which together with the detailed description below are incorporated in and form part of the specification, serve to further illustrate various embodiments and to explain various principles and advantages all in accordance with the present invention. 
       Features of the present invention, which are believed to be novel, are set forth in the drawings and more particularly in the appended claims. The invention, together with the further objects and advantages thereof, may be best understood with reference to the following description, taken in conjunction with the accompanying drawings. The drawings show a form of the invention that is presently preferred; however, the invention is not limited to the precise arrangement shown in the drawings. 
         FIG. 1  is as perspective view a separating device, consistent with the present invention; 
         FIG. 2  is a plan view of  FIG. 1 ; 
         FIG. 3  is a perspective view another separating device, consistent with the present invention; 
         FIG. 4  is a plan view of the separating device in  FIG. 3 . 
     
    
    
     In the figures, the same reference numerals identify same or functionally the same elements inasmuch as nothing to the contrary is indicated. 
     Skilled artisans will appreciate that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help to improve understanding of embodiments of the present invention. 
     DETAILED DESCRIPTION 
     Before describing in detail embodiments that are in accordance with the present invention, it should be observed that the embodiments reside primarily in combinations of apparatus components related to a separating device. Accordingly, the apparatus components have been represented where appropriate by conventional symbols in the drawings, showing only those specific details that are pertinent to understanding the embodiments of the present invention so as not to obscure the disclosure with details that will be readily apparent to those of ordinary skill in the art having the benefit of the description herein. 
     In this document, relational terms such as first and second, top and bottom, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. The terms “comprises,” “comprising,” or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. An element preceded by “comprises . . . a” does not, without more constraints, preclude the existence of additional identical elements in the process, method, article, or apparatus that comprises the element. 
       FIG. 1  shows in a perspective view one embodiment of a separating device  1 . A cover element of the separating device  1  is removed in  FIG. 1  in order to allow a view of the interior of the separating device  1 . Also, in the following reference is being had to  FIG. 2  which shows a view II of  FIG. 1 . 
     The separating device  1  comprises a housing  2  that is in plan view approximately half moon-shaped. The housing  2  has in plan view a circular segment-shaped sidewall  3  which is closed off at its open side by two sidewalls  4 ,  5 . The sidewalls  4 ,  5  can meet each other at an angle  6  of between, for example, 170 degrees to 180 degrees. The angle  6  can also be more than 180 degrees, for example, 300 degrees, or less than 170 degrees, for example, only 100 degrees. In the case of the instant embodiment, the angle  6  is 175 degrees. The angle  6  is measured at the respective outer surfaces  7  of the sidewalls  4 ,  5  which are facing away from the interior  11  which is enclosed by the sidewalls  3 ,  4 ,  5 . Accordingly, the sidewalls  4 ,  5  have a bend pointing toward the interior  11 . 
     The sidewalls  4 ,  5  meet at a central axis  12  about which the circular segment-shaped sidewall  3  is curved. The sidewalls  4 ,  5  form in the area of the central axis  12  a receptacle  13 . In the receptacle  13  a shaft  14  is supported so as to be rotatable about the central axis  12 . On the shaft  14  a flap  15  is fixedly secured so that the flap  15  is pivotable about central axis  12 . The central axis  12  is positioned in the main plane of extension  18  of the flap  15 . The flap  15  extends from the shaft  14  into the interior  11 . In the interior  11  and radially positioned between the flap  15  and an inner surface  16  of the sidewall  3 , an insert  17  of approximately circular segment shape in plan view is arranged. 
     According to the embodiment, the insert  17  in plan view is approximately of a semi-circular shape. In this context, “radial” refers to the central axis  12 . The insert can be embodied as a monolithic injection molded plastic part. The insert  17  comprises a plurality of nozzles  21 . The nozzles  21  are oriented in radial direction outwardly onto a baffle wall  22  which is embodied in the form of a coating on the inner surface  16 . The baffle wall  22  can have an open and/or porous structure, in particular a nonwoven or a foam. The structure is oil-resistant and temperature-resistant. For example, the structure can be made of plastic fibers or synthetic fibers. 
     The insert  17  has a plurality of elements  23 . Such an element  23  in  FIG. 2  is surrounded by a dash-dotted line. The element  23  has a substantially U-shaped cross-section wherein the free legs  24  of the U-shape are widening in radial direction outwardly, i.e., the spacing between two legs  24  of a U-shaped element  23  becomes larger outwardly in radial direction. Two legs  24  of neighboring elements  23  each form a nozzle  21 . The nozzles  21  have along the central axis  12  a constant opening area  19 , as illustrated in the enlarged illustration of  FIG. 2 . The insert  17  has preferably a constant cross-section along the central axis  12 . 
     The flap  15  has a closed position, a plurality of different intermediate positions, and an open position. In  FIGS. 1 and 2  the flap  15  is arranged in an exemplary fashion in one of the intermediate positions. In its closed position (not illustrated), the flap  15  closes off an inlet  25 . The inlet  25  is formed in the sidewall  5  and is in fluidic communication with a first volume  26  when the flap  15  is in one of the intermediate positions. By means of the inlet  25  an oil-air mixture, in particular an oil mist, is supplied to the separating device  1  from a crankcase of an internal combustion engine. 
     The volume  26  is delimited by the flap  15  and a first number of elements  23  or nozzles  21  as well as an inner surface  27  of the sidewall  5 . The free end  28  of the flap  15  is arranged so as to adjoin a partition in the form of a central section  29  between two legs  24  of an element  23 . In this way, the first volume  26  is sealed relative to a second volume  31  of the separating device  1  even when the existing gap enables a negligible fluid exchange between the volumes  26 ,  31 . The second volume  31  is delimited by a second number of elements  23  or nozzles  21 , the flap  15 , as well as an inner surface  32  of the sidewall  4 . 
     The elements  23 , or the nozzles  21 , are distributed along a circular segment line  30  which extends substantially parallel to the sidewall  3 . The central axis  12  extends through the center point of the circular segment line  30 . Also, spacings  20  between two nozzles  21  each become smaller in the opening direction of the flap  15 . The opening direction is indicated with a corresponding arrow in  FIG. 2 . 
     Relative to the force of gravity  34 , a third volume  33 , defined between the insert  17  and the baffle wall  22 , is in fluidic communication in downward direction with a first outlet  35  in a bottom  36  of the housing  2 . The bottom  36  delimits the interior  11  together with the cover, not illustrated, and the sidewalls  3 ,  4 ,  5  completely. 
     Moreover, in the sidewall  4  a second outlet  37  is arranged which is also in fluidic communication with the third volume  33 . While the first outlet  35  is oriented in the direction of the force of gravity  34 , the inlet  25  as well as the second outlet  37  are each oriented in a plane perpendicular to the force of gravity  34 . In this context, “oriented” relates to the central axis of the outlets  35 ,  37  or the inlet  25 . 
     Moreover, the separating device  1  has a spring  41  which loads the flap  15  into the closing direction. The spring  41 , as indicated, can be a spiral tension spring. Alternatively, the spring  41  can be embodied as a torsion spring which is integrated in particular into the shaft  14 . 
     In the pivot position of the flap  15  which is illustrated in  FIG. 2 , the oil-air mixture is guided by means of the first number of nozzles  21  onto the baffle wall  22  whereupon the oil is separated in downward direction through the first outlet  35  and the air is supplied via the second outlet  37  to an intake manifold of the internal combustion engine. When, for example, the power input of the internal combustion engine is increased, the volume flow from the crankcase (not illustrated) increases so that the flap  15  is opened farther against the action of the spring  41 , i.e., the opening angle  42  is enlarged. Since the spring force of the spring  41  increases with increasing opening action of the flap  15 , the pressure in the first volume  26  would increase in fact. However, since the spacing  20  between the nozzles  21  is reduced with increasing opening action of the flap  15 , relatively more nozzles  21  will communicate fluidically with the first volume  26  than in the case for the smaller opening angle  42 . Accordingly, the pressure in the first volume  26  effectively does not rise, so that despite increasing volume flow a constant outlet speed of the fluid out of the nozzles  21  can be observed. Accordingly, a uniform degree of separation with minimal pressure loss is ensured. 
       FIG. 3  shows in a perspective view a second embodiment of a separating device  1 . The cover element of the separating device  1  is also removed in  FIG. 3  and in  FIG. 4  in order to allow a view of the interior of the separating device  1 . Also, in the following reference is being had to  FIG. 4  which illustrates a view along the central axis into the interior of the separating device. 
     The separating device  1  comprises a housing  2  which in a plan view is approxi-mately of a half-moon shape. In plan view, the housing  2  has a sidewall  3  of a circular segment shape which at its open side is closed off by two sidewalls  4 ,  5 . The sidewalls  4 ,  5  can meet each other at an angle  6  of between, for example, 30 degrees and 180 degrees. The angle  6  can also be more than 180 degrees, for example 300 degrees, or less than 170 degrees, for example only 100 degrees. In the case of the present embodiment, the angle  6  is, for example, between 45 de-grees and 90 degrees, preferably between 80 degrees and 90 degrees. The angle  6  is measured at the respective outer surfaces  7  of the sidewalls  4 ,  5  which are facing away from an interior  11  which is enclosed by the sidewalls  3 ,  4 ,  5 . Accordingly, the sidewalls  4 ,  5  enclose the interior  11  at a slightly acute angle. 
     The sidewalls  4 ,  5  meet in the area of a central axis  12  about which the circular segment-shaped sidewall  3  is curved. In the area of the central axis  12 , adjoining the sidewalls  4 ,  5 , a receptacle  13  is formed. In the receptacle  13  a shaft  14  is provided that is rotatably supported about central axis  12 . On the shaft  14  a flap  15  is fixedly mounted so that the flap  15  is pivotable about the central axis  12 . The central axis  12  is positioned in the main plane of extension  18  of the flap  15 . The flap  15  extends from the shaft  14  into the interior  11 . In the interior  11  and radially positioned between the flap  15  and an inner surface  16  of the sidewall  3 , an insert  17  is arranged that in plan view is approximately of a circular segment shape. According to the embodiment, the insert  17  in plan view is approximately of a quarter circle shape. In this context, “radial” refers to the central axis  12 . The insert can be produced as a monolithic injection molded plastic part. The insert  17  comprises a plurality of nozzles  21 . The nozzles  21  are radially outwardly oriented onto an baffle wall  22  which is in the form of a coating on the inner surface  16 . The baffle wall  22  can be an open and/or porous structure, in particular can comprise a nonwoven or a foam. The structure is oil-resistant and temperature-resistance. For example, the structure can be formed of synthetic fibers. The insert  17  in the embodiment according to  FIG. 3  is embodied as a substantially closed wall wherein the nozzles  21  are formed as bores or holes. They can be embodied with circular, rectangular, triangular or polygonal with more than 4 corners. The nozzles  21  can be distributed across the insert, for example, irregularly, preferably however regularly, along the angle  6  and either each radially and as a whole in a fan shape, as illustrated in  FIG. 3 , or instead aligned parallel to each other, as illustrated in the variant of  FIG. 4 . 
     As also depicted in the embodiments shown in  FIG. 3  and  FIG. 4 , the flap  15  has a closed position, a plurality of different intermediate positions, and an open position. In  FIGS. 3 and 4 , the flap  15  is arranged in an exemplary fashion in one of the intermediate positions. In its closed position (not illustrated), the flap  15  closes off an inlet  25 . The inlet  25  is formed in the sidewall  4  and is in fluidic communication with a first volume  26  when the flap  15  is in one of its intermediate positions. By means of the inlet  25 , the separating device  1  can be supplied with an oil-air mixture, in particular an oil mist, from a crankcase of an internal combustion engine. 
     The volume  26  is delimited by the flap  15  and a first number of elements  23  or nozzles  21  as well as an inner surface  27  of the sidewall  4 . The free end  28  of the flap  15  is arranged adjoining a partition in the form of a center section  29  between two legs  24  of an element  23 . In this way, the first volume  26  is sealed relative to a second volume  31  of the separating device  1  even though the existing gap allows for a negligible fluid exchange between the volumes  26 ,  31 . The second volume  31  is delimited by a second number of elements  23  or nozzles  21 , the flap  15  as well as an inner surface  32  of the sidewall  4 . 
     The nozzles  21  are distributed along a circular segment line  30  which extends substantially parallel to the sidewall  3 . The central axis  12  extends preferably through the center point of the circular segment line  30  or is adjacent thereto. Also, preferably the spacings  20  between two nozzles  21  each become smaller in the opening direction of the flap  15 . The opening direction is indicated with a corresponding arrow in  FIG. 4 . Alternatively, the spacing in the circumferential direction can be designed to be constant. 
     A third volume  33  which is defined between the insert  17  and the baffle wall  22  is in fluidic communication in downward direction, relative to the force of gravity  34 , with the first outlet  35  in a bottom  36  of the housing  2 . The bottom  36  delimits together with the cover, not illustrated, and the sidewalls  3 ,  4 ,  5  the interior  11  completely. 
     Also, in the sidewall  3  a second outlet  37  is arranged which is also in fluidic communication with the third volume  33 . While the first outlet  35  is oriented in the direction of the force of gravity  34 , the inlet  25  as well as the second outlet  37  are oriented each in a plane perpendicular to the force of gravity  34 . In this context, “oriented” refers to a central axis of the outlets  35 ,  37  or the inlet  25 , respectively. When an arrangement is to be provided in which the bottom  36  is perpendicular to the force of gravity, the second outlet  37  is arranged in the bottom. The same holds true accordingly for an arrangement in which one of the sidewalls  3 ,  4  would be oriented perpendicular to the force of gravity; in this case, the second outlet would be arranged in them, respectively. 
     Moreover, the separating device  1  has a spring  41  which loads the flap  15  in the closed position. The spring  41 , as illustrated, can be embodied as a spiral tension spring. Alternatively, the spring  41  can be embodied as a torsion spring which is integrated in particular into the shaft  14 . 
     In the pivot position of the flap  15  as illustrated in  FIG. 4 , the oil-air mixture is deflected by means of the first number of nozzles  21  onto the baffle wall  22  where-upon the oil is separated in downward direction via the first outlet  35  and the air is supplied by the second outlet  37  to an intake manifold of the internal combustion engine. When now, for example, the power input of the internal combustion engine increases, the volume flow from the crankcase (not illustrated) thus increases so that the flap  15  is opened farther against the action of the spring  41 , i.e., its opening angle  42  increases. Since the spring force of the spring  41  with increasing opening of the flap  15  increases, actually the pressure in the first volume  26  would rise. However, since the spacing  20  between the nozzles  21  with increasing opening of the flap  15  is reduced, relatively more nozzles  21  will come into fluidic commu-ni-cation with the first volume  26  than in case of smaller opening angles  42 . Accordingly, the pressure in the first volume  26  effectively does not rise so that despite increasing volume flow a uniform exit speed of the fluid from the nozzles  21  is observed. As a result, a uniform degree of separation with minimal pressure loss is ensured. 
     In the foregoing specification, specific embodiments of the present invention have been described. However, one of ordinary skill in the art appreciates that various modifications and changes can be made without departing from the scope of the present invention as set forth in the claims below. Accordingly, the specification and figures are to be regarded in an illustrative rather than a restrictive sense, and all such modifications are intended to be included within the scope of the present invention. The benefits, advantages, solutions to problems, and any element(s) that may cause any benefit, advantage, or solution to occur or become more pronounced are not to be construed as a critical, required, or essential features or elements of any or all the claims The invention is defined solely by the appended claims including any amendments made during the pendency of this application and all equivalents of those claims as issued.