SEPARATOR PLATE FOR AN OIL MIST SEPARATOR AND OIL MIST SEPARATOR

Abstract

A separator plate having a receptacle for a drive shaft that defines an axis of rotation. Such plate, which includes a first annular region radially adjacent to the receptacle, a second annular region radially adjacent to the first annular region, and a third annular region radially adjacent to the second annular region, can be produced particularly easily if the second annular region has a plurality of spokes connecting the first and the third annular regions to one another and if there are flow channels extending in the axial direction between the spokes.

Claims

1.-15. (canceled)

16. A separator plate having an axis of rotation thereof and comprising a receptacle configured to accept a drive shaft along the axis of rotation, and further comprising a first ring area radially adjoining the receptacle, a second ring area radially adjoining the first ring area, and a third ring area radially adjoining the second ring area, wherein the second ring area contains multiple spokes that connect the first and third ring areas to one another to form axially extending flow channels between the spokes, wherein the separator plate has at least two sprues arranged rotationally symmetrically with respect to the axis of rotation, and wherein the spokes that are adjacent to a sprue location have at least one section with a tapered cross-sectional area, wherein the cross-sectional area is an area of a circular cylinder around the axis of rotation, and wherein the at least one section with the tapered cross-sectional area is farther away from the axis of rotation than the sprue location.

17. A separator plate according to claim 16, wherein a material of the separator plate is a partially aromatic polyamide.

18. A separator plate according to claim 16, comprising at least one web adjoining at least one spoke along a radial direction of the plate, wherein the at least one web is configured as a thickened portion of a wall of a conical section of the third ring area.

19. A separator plate according to claim 18, wherein each of at least two adjacent spokes is adjoined in the radial direction by a corresponding web of the at least one web, and further comprising at least one intermediate web disposed between said corresponding webs.

20. A separator plate according to claim 18, wherein cross-sectional area of the at least one web and/or a cross-sectional area of the at least one intermediate web is dimensionally tapered in the radial direction.

21. A separator plate according to claim 20, wherein a cross-sectional area of the intermediate web at a given radius of the separator plate is greater than each of respective cross-sectional areas of the two webs immediately neighboring the intermediate web at the same given radius.

22. A separator plate according to claim 18, wherein the at least one web that is not directly adjacent to a sprue location has a section in which a corresponding cross-sectional area of the at least one web, as seen along the radial direction, is initially reduced and then enlarged again.

23. A separator plate according to claim 19, wherein a thickness of a wall of the third ring section measured between two adjacent webs and/or between the at least one web and the at least one adjacent intermediate web along a circumference of the third ring section and/or measure in the radial direction is maintained within 10%.

24. A separator plate according to claim 16, comprising a ridge as seen along the axis of rotation, said ridge adjoining at least one spoke, of the multiple spokes, and extending in a radial direction along a conical section of the third ring area.

25. A separator plate according to claim 24, wherein the at least one web or the ridge has a height h measured perpendicularly to a surface of the conical section, said height h being less than or equal to 0.3 mm.

26. An oil mist separator comprising a housing that includes at least one gas inlet, at least one gas outlet, and at least one oil outlet, and further comprising at least one separator plate according to claim 16 that is positioned on a rotationally driven shaft in the housing.

27. An oil mist separator according to claim 26, wherein at least two separator plates according to claim 16 are stacked one above the other on the rotationally driven shaft in the housing with a gap between the first ring areas of the at least two separator plate having a gap thickness of less than or equal to 1 mm.

28. An oil mist separator according to claim 27, wherein the gap between the first ring areas of the at least two separator plates stacked one above the other is less than or equal to 0.8 mm.

29. A stack of separator plates, wherein the stack of separator plates comprises at least one separator plate of claim 16.

30. A separator plate according to claim 24, wherein the at least one web the rib has a height h above the wall of the conical section, said height h being less than or equal to 0.2 mm.

31. An oil mist separator according to claim 26, wherein at least two separator plates according to claim 16 are stacked one above the other on the rotationally driven shaft in the housing with a gap in-between the first ring areas of the at least two separator plate having a gap thickness of less than or equal to 0.6 mm.

32. An oil mist separator according to claim 26, wherein at least two separator plates according to claim 16 are stacked one above the other on the rotationally driven shaft in the housing with a gap in-between the first ring areas of the at least two separator plate having a gap thickness of less than or equal to 0.3 mm.

33. An oil mist separator according to claim 27, wherein the gap between the first ring areas of the at least two separator plates stacked one above the other is less than or equal to 0.2 mm.

34. A separator plate according to claim 24, wherein said rib is formed on said conical section that has a wall of a substantially constant thickness.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In the following, the invention will be described by way of non-limiting examples of embodiments, without limitation of the general inventive concept, and with reference to the corresponding drawings, of which:

[0034] FIG. 1 shows a plan view of an embodiment of a separator plate;

[0035] FIG. 2 illustrates a detail of the embodiment of FIG. 1;

[0036] FIG. 3 shows a further detail of the separator plate;

[0037] FIG. 4 depicts a portion of a cross-sectional view of two stacked upon one another separator plates, each structured according to an embodiment of FIGS. 1 to 3;

[0038] FIG. 5 shows in a sequence of images representing the result of a simulation of filling an injection mold for an embodiment of a separator plate;

[0039] FIG. 6 provides a detail of a related cooperation of two separator plates, and

[0040] FIG. 7 shows a detail of yet another related cooperation of two separator plates with one another.

[0041] Generally, the drawings are not to scale. Like elements and components are referred to by like labels and numerals. For the simplicity of illustrations, not all elements and components depicted and labeled in one drawing are necessarily labels in another drawing even if these elements and components appear in such other drawing.

[0042] While various modifications and alternative forms, of implementation of the idea of the invention are within the scope of the invention, specific embodiments thereof are shown by way of example in the drawings and are described below in detail. It should be understood, however, that the drawings and related detailed description are not intended to limit the implementation of the idea of the invention to the particular form disclosed in this application, but on the contrary, the intention is to cover all modifications, equivalents and alternatives falling within the spirit and scope of the present invention as defined by the appended claims.

DETAILED DESCRIPTION

[0043] FIG. 1 shows a plan view of an embodiment of a separator plate 1. As shown, the separator plate 1 has three ring-shaped areas. The first ring area 10 is limited radially on an inward side by a receptacle 3, dimensioned to accept a drive shaft (not shown). The common axis of rotation of the shaft and the separator plate 1 runs orthogonally to the drawing plane and is identified by the reference sign 2. The first ring area 10 merges radially on the outward side with a second ring area 20, which is essentially formed by preferably spatially-evenly arranged spokes 21 and the openings 22 defined by and located between the immediately-neighboring spokes 21. Such openings 22 define the flow channels for the oil mist. The outer ends of the spokes 21 are at a ring 35 that identifies the inner edge of the third ring area 30. The third ring area 30 extends up to the edge 99 of the separator plate 1, which terminates the outer portion of the plate 1 radially. The limits between the ring areas 10, 20, 30 are drawn as dashed lines. The respective adjacent ring areas 10 and 20, as well as the ring areas 20 and 30 are sequentially adjoining one another, preferably without a transition. (In the example of Figure as shown, the ring area 20 is substantially circumscribing the ring area 10, while the ring area 30 I substantially circumscribing the ring area 20.) The corresponding radial extension of each of the ring areas is shown by the corresponding double arrow. The third ring area 30 includes sections 31 having substantially conical surfaces (which makes sections 31 to be conical sections of the third ring area), sections 31 adjoining the ring 35, with the axis of rotation 2 defining axes of the corresponding cones (cf. FIG. 2 and FIG. 3).

[0044] The receptacle 3 dimensioned to accept the shaft is a through-hole 3 centrally-located in the embodiment 1. The contour of the through-hole 3 preferably has a discontinuous rotational symmetry, as shown, such that no imbalance arises, but a torque-transmitting positive locking of the separator plate 1 with a complementary shaft (when cooperated with the plate 1) is possible. Other possibilities for torque-transmission, such as a frictional connection between the shaft and/or stacked separator plates 1 are also possible.

[0045] The example shown has a plurality of webs 40 on its top side, each of which is preferably arranged as the radial extension of a corresponding spoke 21, when regarded in plan view. Optionally or alternatively, at least one intermediate web 50, respectively, is arranged between each of the two neighboring webs 40. The webs 40 and the intermediate webs 50 are elevations in the top side of the third ring area 30. Apart from having such elevations, the third ring area 30 preferably at least substantially has the surface of a cone segment (e.g., of a truncated cone). In the assembled state of the separator plate 1, the webs 40 and the intermediate bars 50 serve as spacers that contact and rest on an underside of another shown separator plate 1 when such additional separator plate 1 is stacked on the shaft above the given separator plate 1.

[0046] FIG. 2 shows a detail of the separator plate 1 in a perspective view, specifically a section of the second ring area 20 with sections of the adjoining first and third ring area 10 and 30, respectively. On the underside of a spoke 21, an injection nozzle 80 of an injection mold is sketched (shown as a truncated cone in a schematically simplified manner; see also FIG. 3). The flattened peak of the truncated cone consequently defines a sprue location. In this example, the flattened peak starts on the underside of the separator plate 1, more precisely on a spoke 21 (that is, in the second ring area 20). In the sense of the above description, the spoke 21 is therefore a spoke 21 close to the sprue. The flattened peak could, however, also start on the top side and/or in the first area 10.

[0047] The spoke 21 in the vicinity of the sprue has an area 23 with a tapered cross-sectional area. In manufacturing, this area is realized by a projection of the injection mold. The plastic melt can therefore not only flow radially outward exclusively from the sprue location via the spoke 21 close to the sprue, but will flow outward via the first area 10 (i.e. the corresponding cavity of the injection mold) via other spokes 21 (i.e. also via spokes 21 remote from the sprue). As a result, the flow front is evened during the injection molding of the third ring area 30, such that it can be manufactured with a reduced wall thickness.

[0048] The ring 35 is attached to the spokes 21 radially on the corresponding outer ends. According to the above classification, the ring 35 is part of the third ring region 30. In comparison to the flat parts of the third ring region 30, the ring 35 has a greater material thickness, accordingly the corresponding ring channel of the injection mold having a larger free cross-section. In operation of the separator ring 1, the plastic melt can therefore evenly distribute in the peripheral direction, before it enters the annular gap to form the conically-surfaced section 31 of the third annular region 30.

[0049] In the area of the webs 40, the injection mold has a radial channel which counteracts a uniform expansion of the plastic melt, because the plastic melt would spread more quickly in this channel. In addition, at least part of the plastic melt shoots into the webs 40 (more precisely the corresponding recess) located in the radial extension of the spokes 21. An optional cross-sectional tapering 43 of profiles of the webs 40 at their inlet-sided end region can counteract an uneven expansion of the plastic melt during injection molding. The first quarter (preferably first fifth, even more preferred first eighth or first tenth of the corresponding web 40), which lies inwardly with respect to (the closest to) the axis of rotation 2, is herein referred to as the inlet-sided end region.

[0050] The optional intermediate webs 50 also contribute to evening the spread of the plastic melt, since the injection mold forms a channel with an enlarged cross-section at the corresponding location. This channel lies precisely in the area that is furthest away from the webs 40 (cf. FIGS. 1 to 3) and thus prevents a weld line that would otherwise be expected there. It can be clearly seen in FIGS. 2 and 3 that the intermediate webs 50 are shown wider than the webs 40 (that is, a cross-sectional area of the web 50 at a given radius of the plate 1 is larger than a cross sections area of any of webs 40 at the same radius) in order to compensate for the pressure drop in the injection mold by means of a larger flow cross-section. The height h (thickness) of the webs 40 and preferably also of the intermediate webs 50 is preferably at least approximately the same (with the value deviating within about ±10% from the nominal value) and at least approximately the same (±10%) over the distance from the axis of rotation 2 (with the exception of the cross-sectionally tapered areas 43). The indication “(±10%)” is intended to clarify that “at least approximately or at least substantially the same” means equal to as well as deviations from the mean value of up to 10% of the mean value. Smaller deviations of up to ±5%, up to ±2.5% or up to 1% are increasingly preferred with decreasing size.

[0051] As shown, it is advantageous if the cross-sectional area of the webs 40 and/or of the intermediate webs 50 tapers in radial direction, in order to reduce the pressure drop in the channels forming the later webs 40 or intermediate webs to be reduced, such that a flow front that is generated as uniform as possible over the periphery. The separator plate is therefore less prone to weld lines.

[0052] FIG. 4 shows a cross-section which was placed along a circular cylinder surface around the axis of rotation in the third ring area, with the viewing direction radially outwards. The thickened portion of the radially outwardly tapering webs with the height h on the surface 31 ascending conically outwards with a wall thickness d can be clearly seen. In this embodiment, the web height h defines the distance between two adjacent separator plates.

[0053] FIG. 5 shows a sequence of images of a simulation of the spread of a plastic melt during the manufacturing of the separator plate shown in FIGS. 1 to 3. As can be clearly seen, the flow front of the plastic mass spreads in a very short time, almost rotationally symmetrical. The tendency to form weld lines is therefore very low. Correspondingly, the wall thickness d in the areas 31 can be particularly small.

[0054] FIG. 6 shows an alternative for the formation of spacers on separator plates 1; the view corresponds to that in FIG. 4. However instead of webs 40, undulations 60 in the third ring area 30 serve are formed (as seen downwards along the axis of rotation 2, these undulations 60 are perceived as ribs or ridges). When viewed from below the separator plate 1 (that is upward along the axis of rotation, the undulations 60 are perceived as grooves in the lower surface of the plate 1. As seen in FIG. 6, the ridges or ribs 60 are configured as spacers providing spatial separation h (defined by the height of a given ridge 60) between the two separator plates 1 stacked on the same shaft as long as ridges 60 of one of the plates are not co-located with the ridges of another of the plates (that is, as long as one of the stacked plates is rotates about the axis of rotation relative to another plate 1 as indicated. As seen from the bottom of a given separator plate 1, the ridges 60 correspond to respective grooves 60. The ridges 60 have the advantage, when compared to the webs 40, that the corresponding injection mold has no areas in which the gap thickness increases (at least significantly). The cross-sectional taperings 43 described above with reference to the webs 40 can therefore be formed smaller on the input side of the ridges 60 or even be omitted entirely. As can be seen, the wall thickness d of the separator plates 1 of the embodiment of FIG. 6 remains substantially (±10%) constant over the entire circumference, i.e. the thickness of the wall thickness of the area 30 at the ridge 60 (as viewed along the axis of rotation) is the same as the thickness of the wall of the area 30 between the ridges 60. Moreover, the ridges 60 are arranged like the webs 40 and/or intermediate webs 50 described above, i.e. they preferably extend at least approximately radially, wherein deviations of ±30° from the respective radial are permissible.

[0055] FIG. 7 shows a related alternative with slightly modified configuration of ridges 60, which configuration prevent ridges 60 stacked on one another from sinking into one another. This is achieved by the fact that the distance between the upper edges 62 of a ridge 60 is greater than the distance between corresponding lower edges 64, wherein the edges 62, 64 are shown rounded in the sketch. In contrast to what is shown in FIG. 6, the contour of the top side of a ridge 60 is not congruent with the contour of the corresponding underside (groove) of the ridge 60. If, as shown in FIG. 7, two similar separator plates 1 are stacked on top of one another, a distance h defined by the height of a given ridge 60 is consequently established between adjacent separator plates 1. In contradistinction with the embodiment of FIG. 6, the thickness of a wall of the area 30 at the ridge 60 in the embodiment of FIG. 7 differs from the thickness of the wall of the area 30 outside of the ridge 60. In this embodiment, it is therefore only important that the bearing surface generated by the ridge 60 on one side is wider than the recess formed on the other side of the ridge 60.

[0056] It will be appreciated to those skilled in the art having the benefit of this disclosure that this invention is believed to provide a separator plate and an oil mist separator. Further modifications and alternative embodiments of various aspects of the invention will be apparent to those skilled in the art in view of this description. Accordingly, this description is to be construed as illustrative only and is provided for the purpose of teaching those skilled in the art the general manner of carrying out the invention. It is to be understood that the forms of the invention shown and described herein are to be taken as the presently preferred embodiments. Elements and materials may be substituted for those illustrated and described herein, parts and processes may be reversed, and certain features of the invention may be utilized independently, all as would be apparent to one skilled in the art after having the benefit of this description of the invention. Changes may be made in the elements described herein without departing from the spirit and scope of the invention as described in the following claims.

LIST OF REFERENCE NUMERALS

[0057] 1 separator plate [0058] 2 axis of rotation [0059] 3 receptacle for shaft [0060] 10 first ring area [0061] 20 second ring area [0062] 21 spoke [0063] 22 openings between adjacent spokes [0064] 23 area of a spoke with a tapered cross-sectional area [0065] 30 third ring area [0066] 31 conical surface (conical section of the third ring area) [0067] 35 ring [0068] 40 webs [0069] 43 cross-sectional taper of a web [0070] 50 intermediate webs [0071] 60 ridge or rib [0072] 62 upper edges of the ridge or rib [0073] 64 lower edges of the ridge or rib [0074] 80 injector nozzle [0075] 99 edge of the separator plate