EP3765201B1 - Rotor for a centrifugal separator and centrifugal separator - Google Patents

Description

The present invention relates to a rotor of a centrifugal separator, the rotor having a central shaft on which a stack of plates made up of a plurality of identical plates is arranged, the shaft having an engagement contour on its outer circumference for non-rotatable, axially displaceable engagement with a counter-contour on the inner circumference of the plates of the stack of plates, wherein the engagement contour and the counter-contour can be brought into engagement with one another in a plurality of rotational positions spaced apart from one another in the circumferential direction, and wherein each plate has spacers spaced apart from one another in the circumferential direction of the plates, each of which separates two adjacent plates at an axial distance, forming an intermediate flow gap with a predeterminable gap dimension keep from each other. The invention also relates to a centrifugal separator.

The document EP 3 124 120 A1 shows an oil separator configured to separate oil mist from a gas. The oil separator includes a rotor. This rotor has multiple cutting disks stacked along the axis line of a spindle. Each of the separator disks is in the form of a truncated cone plate member and is formed with concave-convex ribs extending radially from the center of rotation on outer peripheral side parts corresponding to the inclined surfaces of the truncated cone. The concavo-convex ribs include first convex portions and second convex portions, the first convex portions on the outer peripheral side parts having a convex shape on the front surface side and a concave shape on the back surface side, and the second convex portions on the outer peripheral side parts include a convex shape on the back and a concave shape on the front. This allows stacks of cutting discs with form a predetermined distance between the individual cutting disks without the need for separate spacers.

The document US 779 099 A shows a centrifugal separator with a rotor, the rotor having a central shaft on which a stack of plates made up of several identical plates is arranged, the shaft having an engagement contour on its outer circumference for non-rotatable, axially displaceable engagement with a counter-contour on the inner circumference of the plates of the stack of plates having. The engagement contour and the counter-contour can be brought into engagement with one another in a plurality of rotational positions spaced apart from one another in the circumferential direction. The plates are corrugated as seen in the plate peripheral direction, with the corrugations each holding two adjacent plates at an axial distance from one another, with the formation of intermediate flow channels with a definable cross section. The corrugated plates are designed in such a way that with different twisted positions of adjacent plates relative to one another in the plate stack, at least two different axial distances with different cross sections of the flow channels between the adjacent plates can be adjusted.

Another rotor of the type indicated above is from the document DE 10 2015 119 616 A1 famous. The plates here have the shape of a truncated cone and the inclined, radially outer part of the plates is designed as a closed surface. The inner circumference of the radially inner, flat area of the plates is provided with the counter-contour to the contour of engagement of the central shaft. Radially outside of the counter-contour are distributed in the circumferential direction several flow openings through which a gas to be cleaned flows axially during operation of the rotor and from where the gas is then deflected radially outwards into the flow gaps between the adjacent plates. An arrangement of spacer webs running over the lower side of the obliquely aligned area of the plates is used here to space the plates from one another.

The document EP 2 349 578 B1 describes a separator disk adapted to be included in a disk pack of a centrifuge rotor. The separator disc has a tapered shape and extends about an axis of rotation and along a tapered rotating symmetrical surface along the axis of rotation. Next, the separator plate has an inner surface and an outer surface. The separating disc is made of a material, the separating disc being configured in a way that it has a clearance between the separating disc and an adjacent separating disc in the disc pack and thus includes first protrusions extending outwardly from the tapered rotating symmetrical surface, and second projections extending inwardly from the tapered rotating symmetrical surface. Each first and second projection defines a contact zone adapted to contact an adjacent separator disk in the disk pack. Here, the contact zones of the first projections are offset with respect to the contact zones of the second projections, seen in a direction normal to the outer face. The first and second projections are sequentially provided in a peripheral direction of the separator disk. What is important here is that the tapered shape and the projections of the separator disc were provided by pressing a blank of the material against a tool part having a shape corresponding to the tapered shape with the projections of the pressed separator disc.

The document EP 2 334 439 B1 shows a disk pack for a centrifuge rotor of a centrifugal separator, which is designed for the separation of components in a medium supplied, the disk pack having a multiplicity of separating plates which are present one on top of the other in the plate pack. Each separator disc extends about an axis of rotation and has a cone-like shape with an inner surface and an outer surface along the axis of rotation. Each separating disk is made from at least one material, with the separating disks in the stack of disks being prestressed against one another with a prestressing force. The separating discs have a plurality of first separating discs, each of which has a number of spacer elements. Each separating plate has at least one section without spacer elements. The first separating discs are polarly positioned in such a way that the spacer elements of one separating disc abut the portion of an adjacent separating disc. It is essential here that the spacer elements have a number of pairs of spacer elements, the pairs each having a first spacer element which extends away from the outer surface and a second spacer element which extends away from the inner surface, the first and second spacers are offset in relation to each other as viewed in a normal direction with respect to the outer surface and sequentially in a peripheral direction of the first separator disc be provided that the prestressing force causes an abutment force between the spacer elements and the adjacent separating disk and an elastic deformation of the section of at least the separating disks, and that this elastic deformation ensures an increase in the abutment force between the spacer elements and the adjacent separating disk during rotation of the disk pack.

A disadvantage of most of the known rotors and plates described above is that the axial distance between adjacent plates in the stack of plates is fixed at a single value, which is determined by the height of the spacer webs or the first and second projections or the spacer elements on the plates is predetermined. If a different axial distance between adjacent plates in the stack of plates is desired or required, it is necessary to manufacture new plates with spacer webs or first and second projections or spacers of a different, smaller or larger axial height. However, such production is unfavorable and, in particular, uneconomical with regard to the necessary investment in tools and the differentiation of parts when assembling the stack of plates. At the rotor according to the document US 779 099 A Although two different disc distances can be set, only relatively narrow flow channels, but no intermediate flow gaps, are provided between the adjacent discs.

The object of the present invention is therefore to create a rotor of the type mentioned at the outset, which avoids the disadvantages mentioned and in which it is possible in a technically simple and economically favorable manner to use different distances and thus different widths of intermediate flow gaps between the to realize plates in a stack of plates. In addition, a corresponding centrifugal separator is to be created.

The solution to the first part of the task relating to the rotor is achieved according to the invention with a rotor of the type mentioned at the beginning, which is characterized in that the spacers of the plates are designed and arranged in such a way that with different rotational positions of adjacent plates relative to one another in the plate stack there are at least two different axial distances with different gap dimensions of the flow gap between the adjacent ones plates are adjustable and that the circumferentially spaced twisted positions, in which the engagement contour and the counter-contour can be brought into engagement with each other, are in two superimposed angular grids that are offset relative to one another in the circumferential direction by an offset angle, with the two angular grids each having a uniform matching grid angular spacing , where the screen angle spacing is an integer fraction of 360° and the offset angle is less than half the screen angle spacing.

The invention advantageously enables stacks of plates to be created from mutually identical plates with at least two different plate spacings in the plate stack, with the respective plate spacing only depending on the relative twisted position of the adjacent plates. Since only one design of plates is required, the tooling costs are advantageously kept low, which results in good economics in the manufacture of plate stacks and rotors for centrifugal separators. In addition, the axial distance between two immediately adjacent plates can be changed here even with a small angular offset by the aforementioned offset angle.

One embodiment of the rotor provides that each plate has first and second spacers and that the first and second spacers differ in terms of their height and/or their radial position on the plate. These spacers are easy to produce and the axial plate spacing can be changed simply by placing two directly adjacent plates on the central shaft, rotated relative to one another by the grid angle spacing or by the offset angle.

Furthermore, it is preferably provided that the first and second spacers are formed by two different humps or beads formed or stamped into the plates, each forming an elevation on one side of the plate and a depression on the other side of the plate. Such spacers can advantageously be produced by simply pressing or embossing, for example.

It is also possible that the spacers, which are spaced apart from one another in the circumferential direction of the plate, are each designed as individual humps or as a radially running row of a plurality of humps.

A further embodiment of the rotor provides that each plate has first and second spacers and that the first and second spacers are formed by webs or nubs that are attached to or formed on the plates and form elevations.

In a further embodiment in this regard, it is proposed that the webs or knobs forming the first spacers be arranged on the top side of the plate, that the webs or knobs forming the second spacers be arranged on the bottom side of the plate and that the webs or knobs forming the first spacers be arranged relative to the webs or nubs forming the second spacers are offset in the circumferential direction of the plate. Here, too, the axial plate spacing can be easily changed by placing two directly adjacent plates rotated by the screen angle spacing on the central shaft, with the upper and lower side spacers of two directly adjacent plates either meeting and causing a larger axial plate spacing or not meeting and bring about a smaller axial disc distance.

A further rotor configuration provides that the webs or knobs forming the first spacers are arranged on the top side of the plate, the webs or knobs forming the second spacers are arranged on the underside on the plate, the webs or knobs forming the first spacers on the the webs or knobs forming the second spacer are arranged congruently and that the angular spacing of the spacers spaced apart from one another in the circumferential direction of the plates corresponds to twice the grid angle spacing. In this rotor design, too, the axial plate spacing can be easily changed by placing two directly adjacent plates on the central shaft, rotated by the grid angle spacing or the offset angle.

In order to keep the production of the plates simple, it is preferably provided that the webs or knobs forming the first spacers, arranged on the top side of the plate, and the webs or knobs forming the second spacers, arranged on the underside of the plate, are identical to one another.

Different rotors are easy to produce with the invention. On the one hand, it is possible for all plates within the plate stack of a first rotor design to have a first, smaller axial distance from one another with a smaller gap, and for all plates within the plate stack of a second rotor design with plates that are identical to the first rotor design to have a second, larger axial distance from each other with a larger gap.

As an alternative to this, there is the possibility that the plates within the plate stack of the rotor have different axial distances.

It is preferably further provided that the plates within the plate stack of the rotor have a smaller axial distance from one another with a smaller gap in a region of the rotor close to the inflow and a greater axial distance from one another with a larger gap in a region of the rotor remote from the inflow. In this way, in particular, a more uniform distribution of a volume flow of a fluid medium to be treated in the rotor over the plurality of flow gaps can be achieved.

In order to keep the production of the individual plates and the plate stack as well as the central shaft of the rotor practicable with regard to their engagement and counter-contours, it is proposed that the engagement contour and the counter-contour should be in two to sixteen, preferably six to twelve, in the circumferential direction of the central shaft and the plate can be brought into engagement with one another in twisted positions spaced apart from one another.

If required, the number of twisted positions in which the central shaft and the plates can be brought into engagement with one another can also be greater than the aforementioned numbers, in which case the grid angle spacing then becomes correspondingly smaller. This can be expedient, for example, if more than two different axial disc distances are to be adjustable.

The disks of the rotor are preferably press-stamped parts made from sheet metal or injection-moulded parts made from plastic. Both types of plates mentioned can be produced comparatively easily and inexpensively and can be provided with the necessary spacers, both of which preferably take place in one operation.

Regardless of the design of the spacers, it is proposed that the engagement contour on the outer circumference of the shaft be formed by a number of n teeth running in the longitudinal direction of the shaft and projecting radially outwards and that the counter-contour on the inner circumference of the plates be formed by a number of n or 2 xn to the teeth matching, radially outwardly facing recesses is formed.

In this case, the number n is preferably between 2 and 8, preferably 3 to 6, in order not to make the production of the engaging and counter-contours too complicated. The number n also depends on the forces to be absorbed during operation of the rotor and acting in the circumferential direction of the rotor between the plates and the central shaft.

The solution to the second part of the task relating to the centrifugal separator is achieved according to the invention with a centrifugal separator which is characterized in that it has a rotor according to one of claims 1 to 15. With such a centrifugal separator, the advantages already explained above in connection with the rotor are achieved.

In a preferred application, the centrifugal separator according to the invention is an oil mist separator for the crankcase ventilation gas of an internal combustion engine and can advantageously serve to effectively separate oil mist and oil droplets from the crankcase ventilation gas of the internal combustion engine. In a rotor of such a centrifugal separator, the discs have a very small distance from one another, in practice, for example, between about 0.3 and 0.5 mm. For this application, the plates can then be designed, for example, so that they form a first distance of 0.3 mm between them in a first relative twisted position and a second distance of 0.5 mm between them in a second relative twisted position. The plates and their spacers can also be designed in such a way that, in a third rotational position relative to one another, they form a third distance between them, for example of 0.4 mm. In this way, needs-based, different gap dimensions between the mutually identical discs of the rotor can be easily adjusted during rotor production.

Figur 1

einen Rotor eines Zentrifugalabscheiders in einer ersten Ausführung, in Ansicht schräg von oben,

Figur 2

den Rotor aus Figur 1 in Draufsicht,

Figur 3

den Rotor aus Figur 2 im Längsschnitt entlang der Schnittlinie III - III in Figur 2,

Figur 4

den Rotor in einer zweiten Ausführung, in Ansicht schräg von oben,

Figur 5

den Rotor aus Figur 4 in Draufsicht,

Figur 6

den Rotor aus Figur 5 im Längsschnitt entlang der Schnittlinie VI - VI in Figur 5,

Figur 7

das in Figur 6 eingerahmte Detail VII in vergrößerter Darstellung,

Figur 8

den Rotor in einer dritten Ausführung, in Ansicht schräg von oben,

Figur 9

den Rotor aus Figur 8 in Draufsicht,

Figur 10

den Rotor aus Figur 9 im Längsschnitt entlang der Schnittlinie X - X in Figur 9,

Figur 11

das in Figur 10 eingerahmte Detail XI in vergrößerter Darstellung,

Figur 12

den Rotor in einer vierten Ausführung, in Ansicht schräg von oben,

Figur 13

den Rotor aus Figur 12 in Draufsicht,

Figur 14

den Rotor aus Figur 13 im Längsschnitt entlang der Schnittlinie XIV-XIV in Figur 13,

Figur 15

das in Figur 14 eingerahmte Detail XV in vergrößerter Darstellung,

Figur 16

einen einzelnen Teller eines Rotors, in einer weiteren Ausführung, in Draufsicht,

Figur 17

einen aus Tellern gemäß Figur 16 erstellten Rotor, in Draufsicht,

Figur 18

den Rotor aus Figur 17 in Schnitt gemäß der Schnittlinie XVIII - XVIII in Figur 17,

Figur 19

das in Figur 18 eingerahmte Detail XIX in vergrößerter Darstellung,

Figur 20

das in Figur 18 eingerahmte Detail XX in vergrößerter Darstellung,

Figur 21

einen oberen Abschnitt einer ersten zentralen Welle als Teil des Rotors nach Figur 17, in Seitenansicht,

Figur 22

die Welle aus Figur 21 im Querschnitt gemäß der Schnittlinie XXII-XXII in Figur 21,

Figur 23

einen oberen Abschnitt einer zweiten, geänderten zentralen Welle als Teil eines Rotors, in Seitenansicht, und

Figur 24

die Welle aus Figur 23 im Querschnitt gemäß der Schnittlinie XXIV-XXIV in Figur 23.

Exemplary embodiments of the invention are explained below with reference to a drawing. The figures of the drawing show:

figure 1

a rotor of a centrifugal separator in a first embodiment, viewed obliquely from above,

figure 2

the rotor off figure 1 in top view,

figure 3

the rotor off figure 2 in longitudinal section along line III - III in figure 2 ,

figure 4

the rotor in a second version, viewed diagonally from above,

figure 5

the rotor off figure 4 in top view,

figure 6

the rotor off figure 5 in longitudinal section along line VI - VI in figure 5 ,

figure 7

this in figure 6 framed detail VII in an enlarged view,

figure 8

the rotor in a third embodiment, viewed diagonally from above,

figure 9

the rotor off figure 8 in top view,

figure 10

the rotor off figure 9 in longitudinal section along line X - X in figure 9 ,

figure 11

this in figure 10 framed detail XI in an enlarged view,

figure 12

the rotor in a fourth embodiment, viewed obliquely from above,

figure 13

the rotor off figure 12 in top view,

figure 14

the rotor off figure 13 in longitudinal section along section line XIV-XIV in figure 13 ,

figure 15

this in figure 14 framed detail XV in an enlarged view,

figure 16

a single plate of a rotor, in a further embodiment, in top view,

figure 17

one made of plates according to figure 16 created rotor, in top view,

figure 18

the rotor off figure 17 in section along line XVIII - XVIII in figure 17 ,

figure 19

this in figure 18 framed detail XIX in an enlarged view,

figure 20

this in figure 18 framed detail XX in an enlarged view,

figure 21

discloses an upper portion of a first central shaft as part of the rotor figure 17 , in side view,

figure 22

the wave out figure 21 in cross-section along section line XXII-XXII in figure 21 ,

figure 23

an upper section of a second, modified central shaft as part of a rotor, in side view, and

figure 24

the wave out figure 23 in cross-section along section line XXIV-XXIV in figure 23 .

In the following description of the figures, the same parts in the various figures are always provided with the same reference numbers, so that not all reference numbers have to be explained again for each figure.

the Figures 1 to 3 The drawings show a rotor 1 of a centrifugal separator, which is otherwise not shown here, in a first embodiment. The rotor 1 has a central shaft 2 on which a stack of plates 3 made up of several identical plates 30 is arranged. The plates 30 each have the known shape of a truncated cone shell and can be made of sheet metal or plastic.

For reasons of clarity, in figure 1 only a few plates 30 drawn; in practice, a stack of plates 3 has up to 100 or more plates 30 .

The shaft 2 has an engagement contour 21 on its outer circumference for non-rotatable, axially displaceable engagement with a counter-contour 31 on the inner circumference of the plates 30 of the plate stack 3, the engagement contour 21 here having the shape of a six-pointed star. The engagement contour 21 and the counter-contour 31 can be brought into engagement with one another in a plurality of relative rotational positions spaced apart from one another in the circumferential direction by a grid angle distance a, here of 60°.

Radially on the outside of the counter-contour 31 are several flow openings 32 distributed in the circumferential direction in the plates 30, through which a fluid medium to be cleaned, such as crankcase ventilation gas of an internal combustion engine, flows axially during operation of the rotor 1 and from where the fluid medium then flows outwards in the radial direction flows into flow gaps 34 between the adjacent plates 30. A reverse flow direction of the fluid medium when the rotor 1 is in operation is also possible.

The separating mechanism of rotors 1 of the type discussed here in centrifugal separators is known and therefore does not have to be explained further here.

The plates 30 have spacers 4, 5, which in the stack of plates 3 hold two adjacent plates 30 at a distance from one another, forming the flow gap 34 between them with a predetermined gap dimension.

The special feature of the plates 30 of the plate stack 3 is that each plate 30 has two such different first and second spacers 4, 5 spaced apart from one another in the circumferential direction of the plates 30 that with different rotational positions of adjacent plates 30 relative to one another in the plate stack 3 there are two different distances with different gap dimensions h ₁ , h ₂ of the flow gap 34 between the adjacent plates 30 can be produced, as can be seen in particular in FIG.

The two different first and second spacers 4, 5 are formed or stamped here by two different ones in the plates 30, each on one side of the plate, here the underside, an increase and on the other side of the plate, here the upper side, forming a depression, arranged in pairs one behind the other in the radial direction.

Seen in the circumferential direction of the plates 30, the first spacers 4 and the second spacers 5 are spaced apart from one another by an angular distance β of 60°. This angular distance β is therefore identical to the grid angle distance α of the engaging and counter-contours 21, 31.

The humps forming the first and second spacers 4, 5 differ here both in their height and in their radial position on the plate 30. The humps forming the first spacers 4 have a greater axial depth and are located somewhat further outwards as seen in the radial direction. The humps forming the second spacers 5 have a smaller axial depth and are located somewhat further inward, viewed in the radial direction, than the humps forming the first spacers 4 .

If, as in figure 3 the two upper immediately adjacent plates 30, which are arranged in a relative rotated position in the plate stack 3, in which the first spacers 4 of one, lower plate 30 are congruent with the second spacers 5 of the other, upper plate 30, then the two adjacent Plate 30 has a smaller distance with a gap dimension h ₁ of the intermediate flow gap 34.

If, as in figure 3 the two lower immediately adjacent plates 30, which are arranged in a relative rotated position in the plate stack 3, in which the first spacers 4 of one plate 30 are congruent with the first spacers 4 of the other plate 30, then the two adjacent plates 30 have a larger one Distance with a gap dimension h ₂ of the intermediate flow gap 34.

To change the gap h between two adjacent plates 30, it is sufficient to place one plate 30 rotated by the spacer angle distance β, with the spacer angle distance β being identical to the grid angle distance α.

In the figure 3 the distances between the plates 30 are exaggerated for reasons of visibility. In reality, the gap h between two adjacent plates 30 is often only a few tenths of a millimeter.

The identical plates 30 within the plate stack 3 of the rotor 1 can therefore have different distances from one another with different gap dimensions h ₁ , h ₂ of the flow gaps 34 . This can be used advantageously, for example, to place the plates 30 at a smaller axial distance from one another with a smaller gap dimension h ₁ in a region of rotor 1 close to the inflow, and to place the plates 30 at a greater axial distance from one another with a larger gap h 1 in a region of rotor 1 remote from the inflow Arranging the gap dimension h ₂ in order to even out the flow through the plate stack 3 .

There is also the possibility that all the plates 30 within the plate stack 3 of a first rotor design have a first, smaller axial distance from one another with a smaller gap dimension h ₁ and that all the plates within the plate stack 3 of a second rotor design with plates 30 that are identical to the first rotor design 30 have a second, larger axial distance from one another with a larger gap h ₂ .

the Figures 4 to 7 show the rotor 1 in a second embodiment. What differs from the first embodiment of the rotor 1 is that the humps forming the first and second spacers 4, 5 are smaller and in the form of radially extending rows of humps, each with four humps. In this way, more points of contact are formed between the respectively adjacent plates 30 in the plate stack 3, which benefits its dimensional stability during operation at high speeds.

Here, too, the humps forming the first and second spacers 4, 5 differ both in their height and in their radial position on the plate 30. The humps forming the first spacers 4 have a greater axial depth and are located somewhat further outwards as seen in the radial direction . The protuberances forming the second spacers 5 have a smaller axial depth and are located somewhat further inward as seen in the radial direction.

Seen in the circumferential direction of the plates 30 there is also an angular distance β of 60° between the first spacers 4 and the second spacers 5 .

This angular distance β is therefore identical to the grid angle distance α of the engaging and counter-contours 21, 31.

If, as in figure 7 the two lower immediately adjacent plates 30, which are arranged in a relative rotated position in the stack of plates 3, in which the first spacers 4 of one plate 30 are congruent with the first spacers 4 of the other plate 30, then the two adjacent plates 30 have a smaller one Distance with a gap dimension h ₁ of the intermediate flow gap 34.

If here as in figure 7 the two upper immediately adjacent plates 30, which are arranged in a relative rotated position in the stack of plates 3, in which the first spacers 4 of one plate 30, in this case the lower one, are congruent with the second spacers 5 of the other plate 30, in this case the upper one, then the two adjacent plates 30 a greater distance with a gap dimension h ₂ of the intermediate flow gap 34.

In its other features and properties, the rotor 1 agrees with the Figures 4 to 7 with the embodiment according to the Figures 1 to 3 match, so reference is made to their description.

the Figures 8 to 11 show the rotor 1 in a third embodiment. What differs from the previously described embodiments of the rotor 1 is that the first and second spacers 4, 5 are now formed by webs which are attached to the plates 30 or formed thereon and form elevations. The spacers 4, 5 formed by the webs here run in a straight line in the radial direction. Alternatively, the spacers 4, 5 can also be curved.

The webs forming the first spacer 4, here three pieces, are arranged on the upper side on the plate 30 and the webs forming the second spacer 5, also three pieces, are arranged on the underside on the plate 30. In addition, here the webs forming the first spacers 4 are offset relative to the webs or knobs forming the second spacers 5 in the circumferential direction of the plate 30 . The angular distance β between the three webs forming the first spacers 4 is 120° in each case here. The angular spacing β of the three webs forming the second spacers 5 is also 120° here. The angular distance between in each case a first spacer 4 and a second spacer 5 within the plate 30 is 60°. This angle of 60° corresponds to the grid angle distance α of the different relative rotational positions of the plate 30 to the central shaft 10, in which the two can be brought into engagement with one another by means of the engagement contour 21 and the counter-contour 31.

If, as in figure 10 and shown enlarged in figure 11 the two uppermost immediately adjacent plates 30, which are arranged in a relative rotated position in the plate stack 3, in which the second spacers 5 of one, upper plate 30 are congruent with the second spacers 5 of the other, lower plate 30, then these two adjacent Plate 30 has a smaller distance with a gap dimension h ₁ of the intermediate flow gap 34. The gap dimension h ₁ corresponds to the height of the individual spacers 4, 5 formed by the webs, which are identical to one another here.

If, as in figure 10 and shown enlarged in figure 11 , the second and third plates 30 seen from above are arranged in a relative twisted position in the stack of plates 3, in which the first spacers 4 of one plate 30, here the lower plate, are congruent with the second spacers 5 of the other plate 30, here the upper plate, then have the two adjacent plates 30 have a larger spacing with a gap dimension h ₂ of the intermediate flow gap 34. The gap dimension h ₂ here corresponds to the added height of the spacers 4 and 5 formed by the webs lying one on top of the other.

In its other features and properties, the rotor 1 agrees with the Figures 8 to 11 with the embodiment according to the Figures 1 to 3 match, so reference is made to their description.

the Figures 12 to 15 show the rotor 1 in a fourth embodiment. According to the embodiment of the rotor 1 described above Figure 8 to 11 Here, too, the first and second spacers 4, 5 are formed by webs which are attached or formed on the plates 30 and form elevations.

The webs forming the first spacer 4, here three pieces, are arranged on the upper side on the plate 30 and the webs forming the second spacer 5, also three pieces, are arranged on the underside on the plate 30. Unlike according to the embodiment of the rotor 1 described above Figure 8 to 11 Here the webs on the upper side forming the first spacers 4 are arranged congruently with the webs on the lower side forming the second spacers 5 . The angular distance β between the three webs forming the first spacers 4 is 120° in each case here. The angular spacing β of the three webs forming the second spacers 5 is also 120° here. The angular distance β between each two spacers 4, 5 corresponds here to twice the grid angle distance α of the different relative rotational positions of the plate 30 to the central shaft 10, in which the two can be brought into engagement with one another by means of the engagement contour 21 and the counter-contour 31.

If, as in figure 14 and enlarged in figure 15 shown from above using the example of the second and third plates 30, the two plates 30 are arranged in a relative rotational position to one another in the plate stack 3, in which the first spacers 4 of one, upper plate 30 are not congruent with the second spacers 5 of the other, lower Plates 30 lie, but are rotated relative to each other by the grid angle distance α = 60°, then these two adjacent plates 30 have a smaller axial distance with a gap dimension h ₁ of the intermediate flow gap 34. The gap dimension h ₁ corresponds to the height of the individual through the spacers 4, 5, which are identical to one another here.

If, as in figure 10 and enlarged in figure 11 shown from above using the example of the third and fourth plates 30, the two plates 30 are arranged in a relative rotational position to one another in the plate stack 3, in which the first spacers 4 of one plate 30, here the lower plate, are congruent with the second spacers 5 of the other, here the upper plate 30, then the two adjacent plates 30 have a larger axial distance with a gap dimension h ₂ of the intermediate flow gap 34. The gap dimension h ₂ here corresponds to the added height of the superimposed spacers 4 and 5 formed by the webs.

In its other features and properties, the rotor 1 agrees with the Figures 12 to 15 with the embodiment according to the Figures 8 to 11 match, so reference is made to their description.

the Figures 16 to 20 show plate 30 and the rotor 1 in a further embodiment. According to the embodiment of the rotor 1 described above Figure 12 to 15 Here, too, the first and second spacers 4, 5 are formed by webs which are attached or formed on the plates 30 and form elevations.

The webs forming the first spacer 4, here three pieces, are arranged on the upper side on the plate 30 and the webs forming the second spacer 5, also three pieces, are arranged on the underside on the plate 30. Here, too, the webs on the upper side forming the first spacers 4 are arranged congruently with the webs on the lower side forming the second spacers 5 . The angular distance β between the three webs forming the first spacers 4 is 120° in each case here. The angular spacing β of the three webs forming the second spacers 5 is the same and is also 120° here.

In contrast to the exemplary embodiments described above, the example according to FIG Figures 16 to 24 that on the inner circumference of the plate 30, the counter-contour 31 is changed. Here, for the counter-contour 31 , two angular grids are provided which are superimposed and offset relative to one another in the circumferential direction by an offset angle δ. The two angle grids each have a uniform matching grid angle distance α, here 60°. The screen angle distance α can also have a different value; however, it always corresponds to an integer fraction of 360°. The offset angle δ is less than half the screen angle distance a; here the offset angle δ is 15°.

This ensures that the circumferentially spaced twisted positions, in which the engaging contour 21 and the counter-contour 31 can be brought into engagement with one another, lie in two superimposed angular grids offset in the circumferential direction by the offset angle δ. In comparison with the exemplary embodiments described above, there is twice the number of relative rotational positions between the central shaft 2 and a plate 30 in each case, in which their engagement contour 21 and counter-contour 31 can be brought into engagement with one another.

Thus, the spacers 4, 5 of two plates 30 adjacent to one another in the plate stack 3 can either be positioned congruently to one another axial distance between the two plates 30 with a larger gap h ₂ between them, or positioned at two different distances from one another in the circumferential direction in non-congruent relation to one another in order to produce an axial distance between the two plates 30 with a smaller gap h ₁ between them .

If the small gap h ₁ is selected, the circumferentially adjacent spacers 4, 5 of two axially adjacent plates 30 in the plate stack 3 are only separated by the offset angle δ, ie by 15° in the example shown. Alternatively, the circumferentially adjacent spacers 4, 5 of two axially adjacent plates 30 in the stack of plates 3 can also be spaced apart by the grid angle distance a, here 60°, or by an angle α-δ, i.e. 45° here. Great flexibility in designing the stack of plates 3 is thus achieved here.

If, as in figure 18 and enlarged in the Figures 19 and 20 shown from above using the example of the second and third plate 30, the two plates 30 are arranged in a relative rotated position in the stack of plates 3, in which the spacers 4, 5 of the two plates 30 are not congruent with one another, but rotated relative to one another out of alignment are, then these two adjacent plates 30 have a smaller axial distance with a gap dimension h ₁ of the intermediate flow gap 34.

If as left in figure 18 and enlarged in figure 19 shown from above using the example of the first and second plate 30, the two plates 30 are arranged in a relative rotational position to one another in the plate stack 3, in which the first spacers 4 of one plate 30, here the lower plate, are congruent with the second spacers 5 of the other, here upper plate 30, then the two adjacent plates 30 have a larger axial distance with a gap dimension h ₂ of the intermediate flow gap 34.

In the Figures 18 to 20 only a few plates 30 are shown for reasons of clarity; in practice, stacks of plates 30 consist of a much larger, often three-digit, number of plates 30.

the Figures 21 to 24 finally show two different versions of the central shaft 2, each in longitudinal section and in cross section.

On the first execution after the Figures 21 and 22 has the shaft 2 on its outer circumference as an engagement contour 21 for torsionally receiving plates 30 six parallel to each other in the longitudinal direction of the shaft, evenly spaced from each other in the circumferential direction of the shaft 2, outwardly facing teeth.

In this first example of the shaft 2, the distance between the teeth of the engagement contour 21 in the circumferential direction of the shaft 2 is 60° in each case, ie it corresponds to the grid angle distance a explained above.

In the second embodiment of the shaft 2 after Figures 23 and 24 has the shaft 2 on its outer circumference as an engagement contour 21 for non-rotatably receiving plates 30 three parallel to each other in the longitudinal direction of the shaft, evenly spaced from each other in the circumferential direction of the shaft 2, outwardly facing teeth.

In this second example of the shaft 2, the distance between the teeth of the engagement contour 21 in the circumferential direction of the shaft 2 is 120° in each case, ie it corresponds to twice the grid angle distance a explained above.

The number of teeth forming the engagement contour 21 on the shaft 2 has no influence on the number of possible relative engagement positions of the central shaft 2 and plates 30 . The specific design of engagement contour 21 and counter-contour 31, z. B. the number and/or size of the teeth forming the engagement contour 21 of the shaft 2 and the matching recesses forming the counter-contour 31 on the inner circumference of the plates, depends in particular on the during operation of the rotor 1 between the plates 30 and the shaft 2 occurring mechanical loads.

With all the configurations of the plates 30 described above, rotors 1 with plate stacks 30 can be formed with plates 30 that are completely identical to one another and central shafts 2 that are identical, the plates 30 of which have different axial distances from one another and which therefore provide different gap dimensions h for the flow gaps 34 . <u>List of reference characters:</u> character designation 1 rotor 10 axis of rotation 2 central wave 21 Engagement contour outside on 2 to 31 3 stack of plates 30 Plate 31 Counter-contour inside at 30 to 21 32 Flow openings in 30 33 radially outer edge of 30 34 flow gap 4 first spacers 5 second spacer h, _h1 , _h2 gap dimensions a screen angle spacing of 21.31 β spacer angle spacing δ offset angle

Claims (17)

1. A rotor (1) of a centrifugal separator, the rotor (1) having a central shaft (2) on which a disc stack (3) of a plurality of identical discs (30) is arranged, the shaft (2) having on its outer circumference an engagement contour (21) for a rotationally fixed, axially displaceable engagement with a corresponding contour (31) on an inner circumference of the discs (30) of the disc stack (3), the engagement contour (21) and the corresponding contour (31) capable of being brought into engagement with one another in a plurality of circumferentially spaced-apart rotational positions, and each disc (30) having spacers (4, 5) spaced apart from one another in the circumferential direction of the disc, the spacers keeping each of two adjacent discs (30) at an axial spacing from one another to form an intermediate flow gap (34) with a predeterminable gap dimension (h), characterized in that,

   the spacers (4, 5) of the discs (30) are designed and arranged in such a way that at least two different axial spacings with different gap dimensions (h₁, h₂) of the flow gap (34) between the adjacent discs (30) can be set with different rotational positions of adjacent discs (30) relative to one another in the disc stack (3) and

   the circumferentially spaced-apart rotational positions in which the engagement contour (21) and the corresponding contour (31) can be brought into engagement with one another are located in two superimposed angular grids, offset against one another in circumferential direction by an offset angle (δ), wherein the two angular grids each have a uniform corresponding grid angle spacing (α), wherein the grid angle spacing (α) corresponds to an integral fraction of 360° and wherein the offset angle ( δ ) is smaller than half the grid angle spacing (α) .
2. A rotor according to claim 1, characterized in that each disc (30) has first and second spacers (4, 5) and that the first and second spacers (4, 5) differ by their height and/or by their radial position on the disc (30).
3. A rotor according to claim 2, characterized in that the first and second spacers (4, 5) are formed by two different humps or corrugations formed or embossed into the discs (30), each forming a projection on one disc side and a depression on the other disc side.
4. A rotor according to claim 3, characterized in that the spacers (4, 5) spaced apart from one another in circumferential direction of the disc (30) are each formed as individual humps or as radially extending row of each a plurality of humps.
5. A rotor according to claim 1, characterized in that each disc (30) has first and second spacers (4,5) and that the first and second spacers (4, 5) are formed on the discs (30) by mounted or formed ridges or nubs that form projections.
6. A rotor according to claim 5, characterized in that the ridges or nubs forming the first spacers (4) are arranged on the upper side of the disc (30), that the ridges or nubs forming the second spacers (5) are arranged on the lower side of the disc (30), and that the ridges or nubs forming the first spacers (4) are offset relatively against the ridges or nubs forming the second spacers (5) in the circumferential direction of the disc (30).
7. A rotor according to claim 5, characterized in that the ridges or nubs forming the first spacers (4) are arranged on the upper side of the disc (30), that the ridges or nubs forming the second spacers (5) are arranged on the lower side of the disc (30), that the ridges or nubs forming the first spacers (4) are arranged congruently with the ridges or nubs forming the second spacers (5), and in that the angular spacing (β) of the spacers (4, 5) spaced apart from one another in circumferential direction of the discs (30) corresponds to twice the grid angle spacing (α) .
8. A rotor according to any of claims 5 to 7, characterized in that the ridges or nubs forming the first spacers (4) and arranged on the upper side of the disc (30) and the ridges or nubs forming the second spacers (5) and arranged on the lower side of the disc (30) are identical to one another.
9. A rotor according to any of claims 1 to 8, characterized in that within the disc stack (3) of a first rotor embodiment all discs (30) have a first, smaller axial spacing from one other with a smaller gap dimension (h₁) and that within the disc stack (3) of a second rotor embodiment with discs (30) identical to the first rotor embodiment all discs (30) have a second, larger axial spacing from one other with a larger gap dimension (h₂).
10. A rotor according to any of claims 1 to 8, characterized in that the discs (30) within the disc stack (3) of the rotor (1) have different axial spacings.
11. A rotor according to claim 10, characterized in that the discs (30) within the disc stack (3) of the rotor (1) have a smaller axial spacing from one other with a smaller gap dimension (h₁) in a region of the rotor (1) close to the inflow and a larger axial spacing from one other with a larger gap dimension (h₂) in a region of the rotor (1) remote from the inflow.
12. A rotor according to any of claims 1 to 11, characterized in that the engagement contour (21) and the corresponding contour (31) can be brought into engagement with one another in two to sixteen, preferably six to twelve, rotational positions spaced apart from one another in circumferential direction of the central shaft (2) and the disc (30).
13. A rotor according to any of claims 1 to 12, characterized in that the discs (30) are press-stamped parts made of sheet metal or injection-molded parts made of plastic.
14. A rotor according to any of claims 1 to 13, characterized in that the engagement contour (21) on the outer circumference of the shaft (2) is formed by a number of n teeth extending in the longitudinal direction of the shaft (2) and projecting radially outward, and that the corresponding contour (31) on the inner circumference of the discs (30) is formed by a number of n or 2 x n recesses matching the teeth and pointing radially outward.
15. A rotor according to claim 14, characterized in that the number n is between 2 and 8, preferably 3 to 6.
16. A centrifugal separator, characterized in that it comprises a rotor (1) according to any of claims 1 to 15.
17. A centrifugal separator according to claim 16, characterized in that it is an oil mist separator for the crankcase ventilation gas of an internal combustion engine.

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