Title of Invention

CENTRIFUGAL SEPARATOR.

Abstract The invention relates to a centrifugal separator (100) comprising a centrifugal frame (40), a rotatable vertically arranged spindle (10) provided with a drum (12). and a motor (90) having a vertical rotor axis (91) The spindle (10) is rotatably mounted in a bearing pot (20) and is mounted in a manner that permits it to three-dimenesionally swing about a pivot (G) in relation to the centrifugal frame (40). According to the invention, the motor (90), via the housing thereof, is rigidly fixed to the centrifugal frame (40). whereby the rotor axis (91) of the motor (90) is aligned with the longitudinal axis (11) of the drive spindle (10) when at rest. The rotor of the motor (90) is connected to the spindle (10) at a coupling point (K) via a flexible coupling element (70). The spindle (10) is mounted in the bearing pot (20) at at least two interspaced bearing points (22, 24) by means of antifriction bearings. The bearing pot (20) is joined to the centrifugal frame (40) via elastic bearing elements (50).
Full Text CENTRIFUGAL SEPARATOR
The invention relates to a centrifugal separator with a centrifuge frame, a rotatable, vertically-positioned spindle with a drum mounted on it, and a motor whose rotational axis is positioned vertically, whereby the spindle is supported in a bearing pot so that it may rotate and may be suspended from a pivot point connected to the frame that may move through three dimensions.
Such a centrifugal separator is known from US-A-2827229. In this, the rotor and the frame are connected with each other via an elastic element that allows oscillation of the rotor. However, the rotor may also deviate radially because of the elasticity of the element so that, in addition to the circular motion, unforeseeable relative motions of the rotor axis in the bearing plane are possible.
Such a centrifugal separator is known from DE 31 25 832. In this, the crucial point of the suspended drive components coincides with the pivot that is in the area of the solitary bearing. The rotating unit consisting of spindle and drum is supported in a bearing pot via roller bearings so that it may rotate. The bearing pot including the rotating unit is suspended in the centrifuge frame. For this, slot bushings or similar are
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recommended that allow angular deviation of the rotation axis from the vertical. The mass action of the spindle is reduced by a large factor because of this design configuration. Drums with significantly larger weight and drums driven at different speeds may be used. A high degree of stability results from the short spindle. The known centrifuge is belt-driven, however. The belt is a wear part requiring a higher degree of maintenance. Slippage in the drive belt leads to losses in drive output. Since the friction heat from the slippage can no longer be radiated from the frame to the environment, the frame's heat increases. The known separator with belt drive is therefore undesirable in many explosive environments. Also, the transferable drive output is limited.
DE 37 14 627 Al publishes a centrifugal separator in which the motor is directly connected to the spindle. The centrifuge drum, the spindle, and the motor together form a suspended unit that is so supported via two bearings that pendular motion about a pivot in the area of a lower bearing is possible. The upper bearing is connected with the frame via elastic elements, and thus allows spindle excursion during centrifuge operation. The forces acting on the upper bearing are thus reduced. A disadvantage of this configuration is the fact that the lower bearing must also function as a revolving joint, thus requiring
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special implementation of roller bearings. The size and weight of the motor, and thereby also the motor output, is thus limited by the motor suspended with the spindle and drum.
DE 43 14 440 Cl publishes another centrifugal separator in which the drive spindle, the drum, and the motor rotor are firmly connected with one another and form a rotating system that is supported elastically in a bearing bracket. The bearing bracket and the motor stator are connected together elastically with the centrifuge frame. The rotating system is suspended from a pivot during centrifuge operation. The known design for heavy motors with high output is not suitable because of the inertial forces and bearing loads that must be handled.
The task is therefore to introduce a centrifugal separator that may be used in an explosive environment and with high output standard motors.
This task is solved by a centrifugal separator of the present invention.
The present invention provides a centrifugal separator with a centrifuge frame, a rotatable vertical spindle with a drum attached thereto and with a motor, the rotor axis of which is disposed vertically, the spindle being mounted for rotation in a bearing pot and so as to swing in space about a point of articulation relatively to the centrifuge frame ;
the motor being fixed with its housing rigidly on the centrifuge frame, the rotor axis of the motor being substantially in alignment with the longitudinal axis of the drive spindle in the state of rest of the centrifugal separator,
the rotor of the motor being connected to the spindle at a coupling point by means of a flexurally elastic coupling element, the spindle being mounted in the bearing pot by means of anti-friction bearings at at least two bearing points disposed in spaced relationship, and
the bearing pot being connected to the centrifuge frame via elastic bearing elements,
characterised in that the bearing pot is fitted on the centrifuge frame by a bearing pot collar by means of at least three elastic bearing elements and in that at least three guide pins disposed parallel to the longitudinal axis are fixed on the bearing pot collar and each engage in a
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compatible bore in the centrifuge frame and are disposed to be deformable in the axial direction and/or axially displaceable in the bores.
An advantage here is that the motor is decoupled from the rotational motion of the spindle and drum. The flexible elastic coupling element between spindle and drum can compensate angular displacement and minor radial displacement between the axes so
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that no strong flex load of the motor shaft and motor rotor bearing arises. Thus, low-cost use of standard motors is possible. The mass of the suspended system and of the motor mass is reduced by the fixed mounting of the motor to the centrifuge frame/ and it is possible to use heavy motors with high power output.
Major losses of power output that might lead to warming of the frame no longer occur in the drive train because of the direct coupling of the motor to the spindle, so that the centrifuge based on the invention is basically suited for use in an explosive environment.
Suspension of the rotating system in a bearing pot that is connected via elastic support elements to the frame leads to the fact that angular displacement arises only between the bearing pot and the frame, while the angular displacement between the inner ring and outer ring of a particular bearing is greatly reduced. Thus, standard roller bearings may be used.
The rotating-axis inclination with respect to the vertical created during separator operation causes one of the elastic support elements positioned between the bearing pot and the frame to be compressed while the opposing one is stretched. This compression and stretching of support elements may result with
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the circular motion from distribution of a large number of support elements along the circumference of a collar of the bearing pot.
It is essential to the invention that the bearing pot with a bearing pot collar be mounted with at least three support elements on the centrifuge frame, and if the bearing pot with a bearing pot collar is mounted on the centrifuge frame with at least three elastic support elements, and if at least three guide pins parallel to the longitudinal axis are attached to the bearing pot collar, each of which engages in a compatible hole in the centrifuge frame and are positioned so that they may be deformed along the axial direction and/or may be be axially displaced into the holes. These guide pins may be displaced axially within the hole, or may at least be deformed to the point that a relative movement is possible between the bearing pot collar and frame along the longitudinal axis. While the support elements positioned between the bearing pot collar and the upper side of the centrifuge frame accept the axial forces, the bearing pot is additionally set by the guide pins along the axial direction. It is thus possible that the rotating bearing pot inclines obliquely with the circular motion of the drum and spindle and then again rights itself, and thus maintains a defined position with respect to the centrifuge frame. The pivot
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thus always essentially lies along the longitudinal axis and does not deviate radially.
Further advantageous embodiments of the invention are
described and claimed hereinafter. In the following, the
invention is described in more detail with reference to the
accompanying drawings, which show :
Figure 1 a first embodiment example of the centrifugal
separator of the invention in schematic cutaway
view ; Figure 2 a second embodiment example of the centrifugal
separator of the invention, also in cutaway view ; Figures 3a,3b show the bearing pot as in the embodiment
example in Figure 2 in various angular positions
in cutaway view.
Figure 1 shows a centrifugal separator 100 in a complete cutaway view. A motor 90 is secured to the underside of a centrifuge frame bolted to a base 2 . A bearing pot 20 is installed into the upper side of the frame 40 that is supported by elastic support elements 50 and held by guide pins 30. A vertically-oriented spindle on which a drum 12 is placed is mounted so that it may rotate.
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The spindle 10 is connected to the motor 90 via a flexible elastic coupling element 70. A slotted clutch bearing shell and a feather key may be provided for torque transmission. The longitudinal axis 11 of the spindle 10 and the rotor axis 91 coincide when the centrifugal separator 10 is at rest.
The bearing pot 20 particularly includes a bearing pot collar 21, an upper bearing 22, and a lower bearing 24. The spindle 10 is mounted in the bearings 22, 24 using roller bearings so that it may rotate.
A large number of bearing elements 50 are positioned between the upper side of the frame 40 and the lower side of the bearing pot collar 21 and are distributed about the circumference. Further, at least two guide pins 30 are provided that engage in compatible holes in the centrifuge frame 40. The guide pins 30 are elastically positioned so that they may be displaced radially but are largely inelastic to radial loads.
The spindle 10 is connected to the motor at coupling point K via the flexible elastic coupling element 70 so that angular displacement is allowed between the rotor axis 91 and the longitudinal axis 11 of the spindle 10 that may be attributed to the circular motion of the rotating system consisting of spindle 10 and drum 12. During this, the rotating system oscillates
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about the pivot G; the spindle axis 11 and the rotor axis 91 intersect at the pivot G. The coupling point K is slightly moved outward when the spindle 11 is oblique, whereby the shaft of the motor 90 also experience obliqueness. The coupling point K is positioned as close as possible to the pivot point G in order to keep the angular displacement to be compensated between spindle 11 and rotor axis 91 as small as possible, and thus to keep the load on the bearing in the motor 90 low.
The coupling 70 may further be so configured that a slight radial displacement between the axes 11 and 91 may be compensated. Additionally, a rotation-elastic configuration is possible in order distribute torque peaks during system operation.
It has proved to be particularly suitable if the distance between the coupling point K is 0.1 to 0.25 times the distance of the pivot point G to the center o£ mass S of the rotating system consisting of drum 12 and spindle 10. With this geometry, the load on the bearings of the motor 90 bolted to the frame 40 does not lead to significant shortening of the service life of the motor 90.
In another embodiment example of a centrifugal separator 100' that is shown in Figure 2, the bearing points of the guide pins
30' are positioned so deep in the frame with respect to the coupling element 70 that the pivot G coincides with the coupling point K'. Thus, the obliqueness of the spindle 11 in operation can be compensated within the coupling element 70. During centrifuge operation, the coupling point also remains on the longitudinal axis 91 of the motor 90 so that the rotor axis 91 of the motor 90 does not deviate, and hardly receives any load from the circular motion o£ the rotating system.
Figures 3a and 3b show the direction of the bearing pot 20 with respect to the frame 40 in various positions of the embodiment example of the centrifuge 100' as in Figure 2, in which the pivot point G' coincides with the coupling point K'.
The spindle 10 is supported at the bearing points 22, 24 within the bearing pot 2 0 using roller bearings, particularly angular-contact ball or roller bearings. The guide pins 30' are attached to the bearing pot collar. These include a conic section 32' and a cylindrical section 34' that is installed into a bushing 35'. The bushing 35' preferably surrounds an elastomer layer surrounded by an inner and an outer metal shell. The guide pin 30' is installed into a hole 44' in the frame. 40'. The guide pin 30' is supported rigidly over the bushing 35' radially, while a slight axial displacement of the guide pin 30' within
the hole 44' is possible with an oblique setting of the bearing pot 20.
Further, several support elements 50 are provided between the frame 40' and the bearing pot collar 21 that preferably are made of elastomer materials. The weight forces of the rotating system are transferred from the spindle 10 via the fixed bearing pot 20 to the support elements 50 and then to the frame 40'.
In the initial position shown in Figure 3a, the longitudinal axis 11 of the spindle 10 is positioned vertically, and the support elements 50 receive an equal axial load. A plane of symmetry 36' passes approximately at half height through the center point of the bearing shells 35'. The pivot G' or coupling point K lies at the intersection of the plane of symmetry 36' with the longitudinal axes 91 or 11.
Figure 3b shows an obliqueness of angle ? of the longitudinal axis 11 caused by the circular motion and forces of the rotating system consisting of drum, spindle 10, and the imbalance of the system, and the bearing pot 20 is rotated about the pivot point G by this angle. On the one side, a support element 50 between bearing pot collar 21 and frame 40' is compressed, and one on the other side is stretched. A return moment is created by the spring energy stored in the deformed elastomer support elements
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50 that, together with the angular moment, causes righting of the rotating system.
The left guide pin is displaced downward with the obliqueness o£ the bearing pot 20 in Figure 3b, while the right guide pin is lifted. The axial paths of the guide pins 30' are short since the guide pins are positioned with small radial separation from the pivot point G', and are preferably enabled by the elastic shape of the bushing 35'. It is achieved by the guide pins 30' that the bearing pot 20 is supported rigid radially so that the position of the pivot point g' remains largely constant with respect to the frame 40', and so that the bearing pot 20 on the other hand is flexible with respect to the obliqueness caused by the rotating system.
Since the pivot point G' and coupling point K coincide in the embodiment example of the centrifuge 100' per Figures 2, 3a, and
3b, the displacement by angle a is completely compensated within the coupling element 70 so that the rotor axis 91 maintains its position without change.
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CLAIMS :
1. A centrifugal separator (100; 100') with a centrifuge frame (40; 40 ' ) / a rotatable vertical spindle (10) with a drum (12) attached thereto and with a motor (90), the rotor axis (91) of which is disposed vertically, the spindle (10) being mounted for rotation in a bearing pot (20) and so as to swing in space about a point of articulation (G;G') relatively to the centrifuge frame (40; 40');
the motor (90) being fixed with its housing rigidly on the centrifuge frame (40; 40')/ the rotor axis (91) of the motor (90) being substantially in alignment with the longitudinal axis (11) of the drive spindle (10) in the state of rest of the centrifugal separator (100; 100'),
" the rotor of the motor (90) being connected to the spindle (10) at a coupling point (K) by means of a flexurally elastic coupling element (70), the spindle (10) being mounted in the bearing pot (40; 40') by means of anti-friction bearings at at least two bearing points (22, 24) disposed in spaced relationship, and
the bearing pot (20) being connected to the centrifuge frame (40; 40T) via elastic bearing elements (50), characterised in that the bearing pot (20) is fitted on the centrifuge frame (40; 40') by a bearing pot collar (21) by
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means of at least three elastic bearing elements (50) and in that at least three guide pins (30; 30') disposed parallel to the longitudinal axis (11) are fixed on the bearing pot collar (21) and each engage in a compatible bore (44') in the centrifuge frame (40; 40') and are disposed to be deformable in the axial direction and/or axially displaceable in the bores (44 ' ) .
2. A centrifugal separator (10 0, 100') as claimed in claim 1,
wherein the point of articulation (G; G') is situated in the
region of the plane of symmetry of the bottom bearing point (24).
3. A centrifugal separator (100, 100') as claimed in claim 1 or
2, wherein the distance between the coupling point (K) and the
point of articulation (G) is 0.1 to 0.25 times the distance
between the point of articulation (G) and the centre of gravity
(S) of the rotating system consisting of the drum (12) and spindle (10) .
4. A centrifugal separator (100, 100') as claimed in claim 1 or
2, wherein the coupling point (K) coincides substantially with the
point of articulation (G').
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5. A centrifugal separator (100, 100' ) as claimed in any one of claims 1 to 4, wherein the guide pins {30; 30') are each inserted in the bore (44) via a bush {35').
The invention relates to a centrifugal separator (100) comprising a centrifugal frame (40), a rotatable vertically arranged spindle (10) provided with a drum (12). and a motor (90) having a vertical rotor axis (91) The spindle (10) is rotatably mounted in a bearing pot (20) and is mounted in a manner that permits it to three-dimenesionally swing about a pivot (G) in relation to the centrifugal frame (40). According to the invention, the motor (90), via the housing thereof, is rigidly fixed to the centrifugal frame (40). whereby the rotor axis (91) of the motor (90) is aligned with the longitudinal axis (11) of the drive spindle (10) when at rest. The rotor of the motor (90) is connected to the spindle (10) at a coupling point (K) via a flexible coupling element (70). The spindle (10) is mounted in the bearing pot (20) at at least two interspaced bearing points (22, 24) by means of antifriction bearings. The bearing pot (20) is joined to the centrifugal frame (40) via elastic bearing elements (50).


Documents:

01506-kolnp-2003 abstract.pdf

01506-kolnp-2003 assignment.pdf

01506-kolnp-2003 claims.pdf

01506-kolnp-2003 correspondence.pdf

01506-kolnp-2003 description(complete).pdf

01506-kolnp-2003 drawings.pdf

01506-kolnp-2003 form-1.pdf

01506-kolnp-2003 form-18.pdf

01506-kolnp-2003 form-2.pdf

01506-kolnp-2003 form-3.pdf

01506-kolnp-2003 form-5.pdf

01506-kolnp-2003 g.p.a.pdf

01506-kolnp-2003 letters patent.pdf


Patent Number 208411
Indian Patent Application Number 01506/KOLNP/2003
PG Journal Number 27/2007
Publication Date 27-Jul-2007
Grant Date 26-Jul-2007
Date of Filing 19-Nov-2003
Name of Patentee WESTFALIA SEPARATOR AG.
Applicant Address WERNER-HABIG-STRASSE 1, 59302 OELDE,
Inventors:
# Inventor's Name Inventor's Address
1 MACKEL WILFRIED ZUM SUNDERN 54, 59302 OELDE,
PCT International Classification Number B04B 9/12
PCT International Application Number PCT/EP02/05664
PCT International Filing date 2002-05-23
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 101 25 808.9 2001-05-26 Germany