FR2754470A1 - OIL SEPARATOR DEVICE, PARTICULARLY FOR MOTOR VEHICLES - Google Patents

Abstract

Oil separator device comprising a housing (3). The separator element comprises a first electrode (15) and a second electrode (17) connected to the high voltage source; the two electrodes are placed in the path of circulation of the oil / gas mixture and have a different polarity.

Description

State of the art

  The present invention relates to a device se-

  oil separator, especially in internal combustion engines

  dull motor vehicle, to separate the oil from the oil / gas mixture, comprising an oil separating element

placed in a housing.

  During the operation of the combustion engine

  internal, leaks, weak at the level of the

  The piston ring tervales create a loss of pressure so that the combustion gases escape from the combustion chamber and pass into the crankcase. In the crankcase, it meets droplets of oil, for example from the camshaft drive chain; these droplets are absorbed by the combustion gases and thus arrive in the combustion process. To reduce the emission of pollutants caused by the combustion of the oil, oil separators have been developed for removing the oil from the oil / gas mixture. There are thus known oil separators mainly composed of a lattice of coarse wires constituting condensation points at the level of which the oil droplets accumulate in order to be returned to the oil tank in the form of separate oil intended for go back to

engine oil circuit.

  In addition, oil separators are known.

  reading the cyclone principle, having ribs guiding the

  flow in a housing receiving the oil / gas mixture for

  strongly mix this mixture. The oil is thus separated by the separators not mainly by condensation, but by the inertia effect acting on the oil. As a disadvantage of this known type of separator, is inter alia the fact that it cannot separate in particular small oil droplets. A disadvantage of both types of separators is that their point

  of optimum operation is only reached in station mode-

  of the internal combustion engine; in other words, this corresponds to a constant flow of combustion gas. In

  especially in non-stationary mode, usual for the function-

  normal operation of a motor vehicle, corresponding to the permanent rise and fall of speed, necessary,

  such systems are no longer sufficient to perform a separation

effective oil ration.

  Advantages of the invention The object of the present invention is to remedy these drawbacks and relates to an oil separator device, in particular for internal combustion engines of motor vehicles, intended to separate the oil from an oil / gas mixture, comprising an oil separator element placed in a housing; according to the invention, the separating element

  oil includes first and second electrode re-

  each linked to a high voltage source. The two elect

  trodes are placed in the mixture circulation path

  oil / gas; their polarities are different.

  The invention advantageously uses the electrostatic principle according to which the droplets

  oil loaded at the first electrode are

  drawn by the second electrode and collected by it.

  The oil separator device according to the invention allows a

  very compact construction requiring few parts.

  In addition, it is possible to separate the oil efficiently.

  even in case of non-stationary operation.

  Another advantage of the oil separator device according to the invention is to separate not only the

  oily components of the gas mixture, but also the aqueous components of the blowing gas.

  Another significant advantage of the device

  oil separator is that the separator element is sufficient

  resistant to fouling caused in particular by ad-

  known oil additives constituting sources of fouling.

  According to a preferred embodiment, the invention provides for producing the first electrode as a tubular annular electrode through which the oil / gas mixture passes. With this type of shaping, the oily components can be loaded particularly well and

of the gas mixture.

  Another preferred embodiment of the invention provides that the second electrode downstream of the

  first electrode has a surface and is in particular

  bind in a conical shape; the second electrode is preferably

  rence arranged perpendicularly in the path

  flow of the gas mixture. The second electrode works

  thus functions as a jet breaker plate on which the oil and water components arrive and which accumulate due to the polarity of the electrodes and can no longer be transported

further by gas.

  The accumulated oil / liquid mixture flows thanks to the appropriate shape of the second electrode preferably

  by an evacuation device leading the oil or li-

what about the engine.

  It is particularly advantageous to give the tubular annular electrode a conical shape. The section

  crossing increases in the direction of flow. Befor-

  the opening angle a is between 10 and 20.

  The conical shape makes it possible to reduce the flow speed of the oil / gas mixture allowing a more efficient loading of the

  liquid particles. In addition, the impact speed of the mete

  diaper on the second electrode is decreased so that the

  particles of liquid remain on the electrode and do not risk

  not entrained by the circulation of gases.

  It is particularly advantageous that the second

  conical electrode has a delimited apex angle

  moth by its envelope surface which is preferably understood

between 100 and 1400.

  Another improvement in pre-

  sees having conical electrodes so that its tip

  is turned towards the first electrode and its axis of sy-

  metry preferably coincides with the axis of symmetry of the

first electrode.

  According to another refinement of the performance of

  the second electrode, according to a preferred embodiment

  rentiel, an annular edge parallel to the axis of symmetry extends from the edge of the envelope surface of the electrode towards the first electrode. This on the one hand increases the effective surface of the electrode and on the other hand ensures a further slowing down of the escaping gases so that the residence time of the oil / gas mixture is lengthened in the active range of the second electrode. It is particularly advantageous to produce the housing of the oil separator device in plastic material. According to another advantageous embodiment of

  the invention, downstream of the second electrode, there is a

  cond separating element in particular in the form of a trellis

  yarn and / or yarn or polyester nonwoven for drying

  trim any remaining oil or fluid residue from the vein

gas.

  The present invention will be described below using an embodiment shown in the single

attached figure.

  The only figure shows a schematic sectional view

  than the oil separator.

  Example of an embodiment An oil separator device 1 preferably comprises a housing 3 in the form of a pot made of plastic and closed in a sealed manner by a front plate also preferably made of plastic. The

  front plate 5, circular has a connection nozzle

  dement 7, provided in the center and projecting from

  the exterior (relative to the interior of the housing); this august

  tage continues with an inlet nozzle 9, central, projecting inwardly. The two nozzles have a passage providing fluid communication between

  the outside and inside of the housing 3.

  The figure shows that the passage of the connection nozzle 7 is in the form of a conical bore; the area of the section decreases towards the inside of the housing. Contrary to this, passage 9 is a conical bore whose surface

  the section increases towards the inside of the housing.

  To connect a supply line

  form of pipe, the end of the nozzle 7 opposite the plate

  that front has an annular projection 11 serving as

hanging means.

  The inner wall 13 of the inlet nozzle 9 is coated with an electrode 15 connected to a high voltage source, not shown. The electrode 15 is thus shaped

  tubular; because of its section, this electrode is called

  the annular electrode. As its wall thickness is

  constant in the longitudinal direction, the annu-

  the area 15 has a cross-sectional area crossed by the fluid which increases towards the inside of the housing. Preferably, the angle at the top of the envelope surface of

  the annular electrode, i.e. the angle a is included in

be 10 and 20.

  A surface-shaped electrode 17 is provided inside the housing 3; the surface of this electrode is directed transversely to the longitudinal axis of the nozzle

  inlet 9 and thus of the direction of arrival of the fluid.

  The electrode has a cone shape, the tip of which faces the front plate 5. An annular edge zone 19 is

  curved towards the front plate 5 and extends essentially-

  ment parallel to the longitudinal axis of the conical electrode 17. The longitudinal extension of the edge area 19

  essentially corresponds to the height of the coni-

  as 17. Thus, the electrode 17 has in section a shape of M. It is advantageous to have as an opening angle formed by the envelope surface of the conical electrode, an angle between 100 and 1400. The electrode conical 17 is also connected to the high voltage source, not shown; the two electrodes 15, 17 are at a different polarity. The figure further shows that the diameter of the conical electrode 17 is considerably larger than the largest internal diameter of the annular electrode 15. The diameter of the conical electrode 17 is however slightly less than the corresponding internal diameter of the housing 3 of

  so as to form an annular interval 21.

  On the side of the conical electrode 17 opposite the axis

  front 5 hereinafter abbreviated as conical electrode

  that, there is provided a gas deflection device 23 which comprises a housing 25 and a pipe 27. The housing 25

  preferably cylindrical has a front surface 29 equal

  conical fit to the shape of the conical electrode. The opposite front face of the housing 25 is closed by an element

  separator 31. The separator element 31 consists of pre-

  ference by a wire mesh or by a yarn or a nonwoven of polyester permeable to a gaseous fluid. A volume 33 delimited by the housing 25 and the two front surfaces 31, 39 communicates with the pipe 27

leaving the housing 3.

  Another pipe 35 opening to the outside is provided in the housing 3 at the level of the front plate 5. The pipe 35 returns to the oil tank of the engine and

  used to collect the water collected by the conical electrode 17.

  The figure also shows that the surface of the conical electrode 17 facing the inlet nozzle 9 is made to allow the oil accumulated on the electrode

  to flow in the direction of the pipe 35.

  The oil separator device works as follows: The oil / gas mixture to be cleaned arrives via the inlet nozzle 7 and circulates inward direction

  of the housing as indicated by an arrow 37. When

  that the inlet nozzle 9 is reached, the oil / gas mixture ar-

  shore in the area of action of the annular electrode 15 which

  electrically charges oil and liquid droplets.

  Due to the increased cross section, the vi-

  flow rate of the gas arriving inside the housing decreases; the travel time by the electrode increases, resulting in an increase in the number of droplets

  of oil and liquid thus charged.

  Downstream of the annular electrode 15, the oil / gas mixture arrives on the surface of the conical electrode 17

  facing the inlet nozzle 9. Due to the polarity

  poured, this conical electrode 17 attracts the droplets of oil and liquid, charged and ensures their separation from the gas circulating in the direction of the annular interval 21. By adjusting the impact speed of the oil / gas mixture, it is necessary to ensure that the electrostatic force exerted by the electrodes on the oil droplets is greater than the

  force exerted by the flow of gas sweeping the electrode.

  Oil and liquid droplets collected

  by the conical electrode 17 form droplets of li-

  that grow and due to gravity, these droplets drip because of the appropriate geometry of the conical electrode 17 to re-supply the engine by the

driving 35.

  The gas stream, cleaned at least in large part of the oil and of the liquid, flows radially outwards on the counter electrode; this flow passes the area

  from edge 19 and crosses annular gap 21 in the di-

  opposite direction to that of the front plate 5 of the housing 3.

  The curved edge area 19 acts as an obstacle and a brake for the flow of gas so that the charged droplets of oil and liquid are sufficiently long in

  the area of action of the conical electrode to be effective-

sensed by it.

  After the gas has passed through the annulus

  area 21, it circulates in the direction of the interior volume 33 of the gas evacuation device 25 and thus travels through the separating element 31. This separating element constituted by a lattice of threads or threads or of polyester nonwoven serves to separate liquid and oil residues that could

subsist in the gas flow.

  From the interior volume 33, the gas clean

  arrives in line 27 and by this it leaves the dispo-

  sitive oil separator and returns in the process of com-

  bustion. This oil separator device makes it possible to arrive at unseparated oil residues in the oil / gas mixture of less than 0.015 g / kW / h. In addition, thanks to its simple and compact construction, the oil separator device can for example be integrated in the case of cylinder heads into the injected cast iron part of the cylinder head. For the rest,

  It is also very easy to fit motors already manufactured.

  in series with this oil separator device because the parts used can easily be adapted to the location

mounting available.

Claims (13)

R E V E N D I C A T I 0 NS   1) Oil separator device in particular in internal combustion engines of motor vehicles, for separating   the oil from the oil / gas mixture, comprising a separate element   oil separator placed in a housing (3), characterized in that the oil separating element comprises a first electrode (15) and a second electrode (17) each connected to a high voltage source, the two electrodes being placed in the circulation path of the oil / gas mixture and   finding at a different polarity.   2) oil separator device according to claim 1, characterized in that the first electrode (15) is an annular electrode of   tubular shape traversed by the oil / gas mixture.   3) Oil separator device according to any one of claims 1 or 2,   characterized in that the second electrode (17) is a surface electrode located   downstream of the first electrode (15).   4) oil separator device according to claim 1, characterized in that the second electrode (17) is arranged transversely to the direction of flow of the oil / gas mixture so that the   mixture abuts on the electrode (17).   5) oil separator device according to claim 2, characterized in that the annular electrode (15) has a section surface   increasing in the direction of flow.   6) Oil separator device according to claim 2, characterized in that   the annular electrode (15) has an opening angle (a) comprising taken between 10 and 20.   7) oil separator device according to claim 1, characterized in that   the second electrode (17) is conical in shape.   8) oil separator device according to claim 7, characterized in that the apex angle formed by the envelope surface of the conical electrode (17) is an angle (f) between 100 and 1400.   ) Oil separator device according to claim 7 and 8, characterized in that the tip of the conical electrode is directed towards the first electrode (15).    ) Oil separator device according to claim 1, characterized in that   the two electrodes (15; 17) are arranged one with respect to   port to the other so that their axes of symmetry coincide.   11) Oil separator device according to any one of claims 1 and 10, characterized in that   the second electrode (17) has a curved edge (19),   parallel to the axis of symmetry with respect to the first electrode (15).   12) Oil separator device according to claim 1, characterized by a discharge device (35) receiving the flowing oil   of the second electrode (17) to evacuate it.   13) Oil separator device according to claim 1, characterized in that the second electrode comprises a gas deflection device (23) traversed by the cleaned gas coming from the device oil separator.   14) Oil separator device according to claim 13, characterized in that the gas discharge device (23) comprises a housing   (25) from which a pipe (27) protruding from the device projects   positive oil separator (1). ) Oil separator device according to claim 14, characterized in that the housing (25) of the exhaust gas guiding device   (23) is closed by another separating element (31) preferably   in the form of a trellis of wires and / or wires or polyester fleece.   16) Oil separator device according to claim 1, characterized in that   it is made of plastic.