EP3240625A1

EP3240625A1 - Rotor of a dual centrifuge

Info

Publication number: EP3240625A1
Application number: EP15808120.8A
Authority: EP
Inventors: Jovan DOBOS; Anke LENZ; Ulrich Massing; Klaus-Günter Eberle
Original assignee: Andreas Hettich GmbH and Co KG
Current assignee: Andreas Hettich GmbH and Co KG
Priority date: 2015-01-02
Filing date: 2015-11-24
Publication date: 2017-11-08
Also published as: DE102015100006A1; US20170348653A1; WO2016107704A1; CN107466251A; US11059007B2; JP6657227B2; JP2018500163A; CN107466251B

Abstract

The invention relates to a rotor (10) of a dual centrifuge, said rotor having a rotor head (12) and an additional rotational mechanism for at least one rotational unit (22) which is provided in the rotor head (12) and comprises a bearing (70) and a rotational head (24) that is connected to the bearing (70), is rotatably mounted therein and can be driven relative to the rotor head (12) by means of the additional rotational mechanism, an opening (16) for the rotational unit (22) being provided in which the rotational unit is accommodated and by means of which the bearing (70) is arranged such that it is fixed relative to the rotor head (12). The invention is characterized in that the rotational unit (22) has a housing (26) in which the bearing (70) is accommodated and in which the rotational head (24) engages, and in that the housing (26) and the rotational head (24) form, with bearing (70), a structural unit, the housing (26) being mounted such that it cannot rotate relative to the rotor head (12) and such that it can be detached from the rotor head.

Description

Rotor of a dual centrifuge

The invention relates to a rotor of a dual centrifuge according to the in the preamble of

Claim 1 specified type.

Dual centrifuges have been known for several years. Whereas in a conventional centrifuge samples are rotated about a single axis, in a dual centrifuge, samples are rotated about a major axis and simultaneously about a minor axis. Due to the resulting high centripetal force and the centrifugal forces acting in different planes, a higher centrifugation efficiency is achieved, especially when mixing, separating or homogenizing samples. DE 10 2012 105 819 A1 discloses a device for homogenizing and separating samples which comprises a centrifuge with a rotor body. In downwardly closed recesses of the rotor body, rotary units are mounted, which are mounted so that they are rotatable about an off-axis of rotation from the motor rotation axis (main axis of rotation). For the rotation units, a separate drive is provided, so that the generation of the rotational movement of the rotation units is independent of the drive of the rotor body.

The above invention is an improvement over the prior art in particular in that lubricant leaving a bearing of a rotation unit remains in the recess associated with the rotation unit and is further available there in the area of the bearing. As a result, significantly longer transit times can be achieved than with solutions from the prior art.

However, it has been found in practice that in devices according to this invention in

Long - term problems with insufficient cooling arise because of the rotation of the Rotation unit accumulates heat in the recess and can not be dissipated. Furthermore, the need for improvement with regard to maintenance, repair and cleaning was recognized. Especially in the rotor body integrated parts of the storage as a bearing outer ring are difficult to access due to the very small dimensions of the recesses.

The object of the invention is to provide a rotor for a dual centrifuge while avoiding the disadvantages mentioned, which simplifies maintenance and reduces downtime. In particular, the rotary units and the recesses associated with the rotary units for the purpose of maintenance, repair and cleaning should be easily accessible and sufficient cooling for long-term operation possible.

This object is achieved by the characterizing features of claim 1 in conjunction with its generic features. The invention is based on the finding that a decoupling of the bearing of the rotary unit from the rotor body creates better conditions for the maintenance, repair and cleaning as well as for the cooling of the rotary unit. In addition, this results in additional design options to optimize maintenance and cooling. According to the invention, the rotor of a centrifuge has a rotor head and another

Rotary mechanism for at least one arranged in the rotor head rotating unit. The turntable includes a bearing and a rotatably mounted rotary head connected to the bearing and drivable relative to the rotor head via the further rotating mechanism. In this case, a recess for the rotary unit or for each rotary unit is provided, in which this is introduced, and thereby the bearing is arranged fixed relative to the rotor head. According to the invention, the rotary unit has a housing into which the bearing is inserted and into which the rotary head engages, and the housing and the rotary head with bearings form a unit, wherein the housing is non-rotatably mounted in the rotor head and detachably mounted therefrom. As a result, the operability and the life of the centrifuge are significantly improved because cleaning, maintenance and repair of the bearing of the rotary unit due to the detachable mounting of the housing in the rotor head are much easier. The turntable can be easily removed from the rotor head and serviced independently of the rotor head. In addition, the turntable can be easily replaced so that downtime due to maintenance is minimized. According to one aspect of the invention, the recesses extend through a region of the rotor head. In this case, the inserted rotary unit passes through the recess, and a lower portion of the housing of the rotary unit protrudes exposed from the recess. By this arrangement, a heat accumulation in the recess is avoided, and the exposed area is cooled by passing air during the rotation. In addition, eliminates due to the recess due to the dimensions of the rotor body length limitation of the rotary unit. With constant dimensions of the rotor body, therefore, longer-sized rotating units can be used, which can accommodate, for example, larger bearings for larger sample vessels. This saves both space and costs.

In a further advantageous embodiment, the rotor head has a rotationally symmetrical

Basic shape with an outer surface, wherein the lower portion of the housing protrudes beyond the outer surface. This embodiment improves the cooling effect, since the protruding portion of the housing of the passing air offers a good attack surface.

It has proven to be particularly efficient if at least 30%, preferably at least 50% of the height of the housing protrude above the outer surface, since then the cooling by the

passing air and the mechanical load / safety in an optimal relationship to each other.

The cooling can be further improved by having it in the lower part of the housing

Cooling fins are provided to increase the cooling surface of the rotary unit.

The cooling fins can be aligned and bent in the direction of rotation of the rotor head, wherein they have a radius starting from the axis of rotation of the rotor head in order to achieve an approximately laminar air flow and flow shadow and thus to avoid uneven cooling of the housing as far as possible. However, numerous experiments have shown that it is even more efficient to cool with a turbulent air flow. Therefore, it is advantageous if the cooling fins are employed at an angle to the direction of rotation.

According to another aspect of the invention, the rotary unit is detachable

Quick release or a screw with the rotor head firmly connected. This facilitates the assembly and maintenance of the rotary unit. In a preferred embodiment, the housing on its side remote from the cooling fins on a flange which bears against the rotor head. The housing is securely fixed in the direction of its longitudinal axis by this flange in the recess associated with the housing. In an advantageous embodiment of the invention, the recess and the housing of the

Rotary unit adapted to each other. As a result, the housing in addition to the direction of its longitudinal axis in other directions can be easily set, which increases the safety of the centrifuge and extends the life of the rotating units. This definition can be further improved by the fact that the cross-sectional shape of the

Housing and the cross-sectional shape of the recess form a rotational security, in particular by a polygonal shape or a cylindrical shape with projections and associated grooves. In this way, an unwanted rotation of the housing about its own axis is avoided in addition to the above-described determination of the housing relative to the rotor head.

According to a further aspect of the invention, the housing and a centric bore housing termination for an axis of rotation of the turret define a storage space with bearings of the axis of rotation. Such a closed storage room has the advantage that in the event of a glass breakage of

Sample containers possible impurities are better limited.

Preferably, the storage space is encapsulated lubricant-tight to the outside. As a result, lubricant leaving a bearing remains in the housing during the entire duration of the centrifugation and is available in the area of the bearing. Thus, the danger of a predator can be significantly reduced. Furthermore, contamination of the rotor head with lubricant is avoided.

It is favorable if the storage space is filled with lubricant, in particular lubricating grease, preferably SKF rolling bearing grease LGBB2 / 0.4. The bearing is in a lubricated state during the entire operating time, which virtually excludes predators. In a preferred embodiment, the storage space to 50% of the height of the storage room with

Filled lubricant. This avoids over-lubrication of the bearing. In order to be able to check the lubrication of the bearing at any time and, if necessary

Refill lubricant, a lubricant refill indicator and / or a lubricant refill valve may be provided. In an advantageous development of the invention, the largest possible part of the surface of the rotary unit is in contact with the rotor head. As a result, optimum heat dissipation from the rotary unit is achieved in the rotor head.

The invention also relates to a rotary unit for a rotor with the features just mentioned.

Further advantages, features and applications of the present invention will become apparent from the following description taken in conjunction with those shown in the drawings

Embodiments.

In the description, the claims, and the drawing, the terms and associated reference numerals used in the list of reference numerals below are used. In the drawing:

1a is a perspective view of a rotor 10 according to the invention with two rotating units 22;

Fig. 1b is a sectional view of the rotor 10 shown in Fig. 1a;

2 shows a perspective view of an embodiment according to the invention of a rotary head 24 without the teeth 36;

3 is a perspective view of an adapter 50 according to the invention;

4 shows an exploded view of a rotary unit 22 according to the invention; Fig. 5a is a view of the rotary unit 22 shown in Fig. 4, and

5b shows a side sectional view of the rotary unit 22 shown in FIGS. 4 and 5a along the section line and cutting direction CC drawn in FIG. 5a. 1a shows a perspective view of a rotor 10 according to the invention with two rotating units 22 for use in a dual centrifuge not shown in the figures. 1 b shows a sectional view of the rotor 10 shown in FIG. 1 a. The rotor 10 has a rotor head 12 with a rotationally symmetrical basic shape, which describes an envelope. The rotor head 12 is provided with a bottom 15 and a bottom 15

circumferential, upwardly extending wall 14 provided. A drive axis A extends perpendicularly through the center 13 of the rotor head 12. A not shown in the figures

Drive shaft passes through with its free end by a provided in the bottom 15 with the

Drive axis A concentric recess 18, the rotor head 12. Above the recess 18 is an integrally formed with the bottom 15 receiving tube 20 is arranged, which serves the centering and vertical fixing of the rotor head 12 on the drive shaft.

The wall 14 has a vertical portion 14a and an obliquely downwards in the direction of the drive axle employed portion 14b. There are two relative to the drive axis A opposing recesses 16 are provided which pass through the vertical portion 14a of the wall 14 and the inclined section 14b of the wall 14 partially. In the recesses 16 each of the rotary units 22 are introduced. The rotary units 22 each have an axis of rotation R1, R2 and are through the

Recesses 16 aligned so that the axes of rotation R1 and R2 intersect the drive axis A above the rotor 10 at an acute angle. Furthermore, the free ends of the rotary units 22 pointing away from the drive axis A, namely the housings 26 explained below, protrude beyond the envelope in the region of the inclined section 14b of the wall 14.

The rotary unit 22 in each case has a largely rotationally symmetrical outer contour and comprises a rotatably mounted rotary head 24 (see FIG. 2) for mounting an adapter 50 for centrifuging (see FIG. 3) and a housing 26 (see FIG. 4) into which a Stock 70 for the

Turret 24 is introduced, in which in turn the rotary head 24 engages with a housing 26 provided on its side facing bearing shaft 25. The bearing shaft 25 is partially visible in Fig. 2 and in Fig. 5b.

The rotary head 24 has an outer wall 24a arranged concentrically with the axis of rotation R1, R2. The housing 26 is arranged with a wall 26a concentric with the axis of rotation R1, R2 Mistake. In this case, the diameter of the rotary head 24 is greater than that of the housing 26, so that between the outer wall 24a and the wall 26a, a shoulder 28 is formed, with which the rotary unit 22 partially engages in the associated recess 16, see Fig. 1a. The housing 26 is adapted in its dimensions to the respectively associated regions of the recesses 16. To produce the rotational strength between the housing 26 and rotor head 12 is in

Housing 26 is provided a parallel to the rotation axis R1, R2 formed groove and on

Rotor head 12 a projection associated with the groove. Groove and projection are not shown in the figures for reasons of clarity. Incidentally, the arrangement of groove and projection can also be reversed. Further, it is conceivable to choose a polygonal design in place of the cylindrical configuration of the housing 26 so as to achieve a rotationally fixed introduction of the housing in the rotor head.

According to FIG. 1a, on the side remote from the housing 26, the rotary head 24 is further closed by a closure cover 30 arranged concentrically with the axis of rotation R1, R2. Likewise concentric on the closure lid 30, a closure button 32 is provided which serves as a handle to unlock the closure cover 30 by a rotary movement and remove or to put on the closure lid 30 and lock by one of the unlocking opposite rotational movement.

On the upper wall 24a, a protrusion 34 is provided circumferentially adjacent to the shoulder 28, see e.g. Fig. 2, which defines a rotatably connected to the wall 24a teeth 36 concentric with the axis of rotation R1, R2. To transmit the rotational movement of the rotary heads 24 about the axes of rotation R1, R2 of the rotary units 22 is provided below the rotor head 12 for each turret 24 each one of the better overview in the figures, not shown gear, which is on the one hand with the teeth 36 in engagement and on the other hand with a central gear 40, which is rotatably connected to the rotatable rotor head 12, for example, by a screw connection to a motor housing, not shown in the figures. Such a transmission of rotational movements is well known and already described in the prior art, so that it can be dispensed with further explanations thereto.

The ratio of main rotation (rotation of the rotor 10) to reverse rotation (rotation of the rotary head 24) is given by the transmission ratio between the unillustrated gear and the central gear 40. When removed rotor head 12, the gear, not shown and the central gear 40 easily interchangeable. Therefore, the speed ratio can be easily changed by adjusting the unillustrated gear and the central gear 40 in diameter. At the remote from the turret 24 side of the housing 26 cooling fins 42 are introduced. The cooling fins 42 are aligned perpendicular to the direction of rotation of the rotor head 12.

Fig. 2 shows a perspective view of an embodiment according to the invention of a rotary head 24 without the teeth 36. The projection 34 has over the entire circumference uniformly spaced recesses 34a, provided by provided on the underside of the teeth 36 screws 36a, shown in Fig. 1a , are penetrated and engage in associated threaded holes in the toothing 36. The recesses 34a by cross-screws 36a put the teeth 36 on the wall 24a and in the turret 24 and in particular ensure the rotational resistance of the toothing with respect to the turret 24 safe.

Within the wall 24a walls 44 are mounted on a bottom plate 24b for fixing an adapter 50 shown in FIG. 3 for centrifuging. The walls 44 form a

Inner profile, which is adapted to the outer profile of the adapter 50 shown in FIG. 3, which has a cross-shaped base of two superposed, concentric at right angles to each other rotated rectangles. The walls 44 are partially connected for better stability. At four walls 44, of which in each case two opposite each other in pairs, each outer profile 44a is formed rounded so that it is concentric with the wall 24a. In the wall 24a, four uniformly spaced holes 24c are introduced adjacent to its upper edge for locking the closure cover 30 having corresponding projections.

Fig. 3 shows in a perspective view the aforementioned adapter 50 for centrifuging. The adapter 50 has on the circumference of the previously described cross-shaped base vertically arranged, integrally formed outer walls 52. Within outer walls 52 five delimited by partition walls 54 rectangular recesses 56 are provided, the vertical extent of the vertical extent of the wall 24a of the rotary head 24 corresponds. The recesses 56 serve to receive not shown in the figures

Sample container receptacles and are adapted to the shape of the sample container receptacles. Adjacent to the free upper edges of the outer walls 52 of the adapter 50 is perpendicular to the outer walls 52 a support surface 58 is arranged, which rests in the inserted state of the adapter 50 on the free upper edges of the walls 44. The support surface 58 has an outer contour 60 which is substantially concentric with the wall 24a of the rotary head 24 and in which four circumferentially equally spaced protrusions 62 are provided. The bulges 62 serve for better handling during insertion and removal of the adapter 50 in or out of the rotary head 24.

4 shows an exploded view of the rotary unit 24 and the housing 26 comprising rotary unit 22 with a housing unit 26 integrated in the storage unit 70 which is concentrically penetrated by a drive shaft, not shown for clarity.

Starting from the housing 26 along the rotation axis R1, R2, a clamping nut 72 for biasing the bearing unit 70, two single row angular contact ball bearings 74a and 74b, disposed between the angular contact bearings 74a and 74b outer disc 76 and an inner disc 78 and a cover 80 are arranged. All of the aforementioned elements of the bearing unit 70 have concentric bores which are passed through the bearing shaft 25 of the rotary head 24 without play.

On the cover 80 eight recesses 82 are provided adjacent to the outer circumference at equal intervals. On the turret 24 side associated with the housing 26 has a flange 84 on which eight recesses 86 are provided at uniform intervals, which are associated with the recesses 82.

In Fig. 5a, a view of the rotary unit 22 is shown from below. In the recesses 82 of the cover 80 each engages a cylinder screw 88, which in the process the associated

Recesses 86 of the flange 84 passes through. Each five recesses 82a and five recesses 86a associated therewith are provided. By the cylinder screws 88 are the

Enclosed housing 26 and the cover 80 so that they define together with the recognizable in Fig. 2 bearing shaft 25 a storage space (64) which is encapsulated lubricant-tight to the outside (see Fig. 5b)

The paired installation of angular contact ball bearings and their bias are well known, so that further explanations are unnecessary. FIG. 5b shows a cross section of the mounted rotary unit 22 shown in FIGS. 4 and 5a along a section CC drawn in FIG. 5a. Between the bottom plate 24b and the

Angular contact ball bearing 74b is provided on the wall 26a a Schmierstoffnachfüllventil with a valve line 92, on the lubricant if necessary in the lubricant-tightly sealed to the outside storage space 64 can be refilled. A lubricant filling indicator 90 arranged outside the housing 26 on the wall 26a serves to control the lubricant level.

LIST OF REFERENCE NUMBERS

rotor

rotor head

center

wall

a vertical section

b obliquely employed section

ground

recesses

recess

pickup tube

rotary unit

turret

an outer wall

b floor plate

c holes

bearing shaft

casing

a wall

paragraph

cap

shutter button

head Start

a recess

gearing

a screws 0 central gear

42 cooling fins

44 walls

44a outer profile

50 adapters

52 outer walls

54 partitions

56 recesses

58 bearing surface

60 outer contour

62 bulges

64 storage room

70 storage unit

72 clamping nut

74a, b Angular contact ball bearings

76 outer disc

78 inner disc

80 cover disc

82 recesses

82a recesses

84 flange

86 recesses

86a recesses

88 cylinder screws

90 lubricant fill indicator

92 lubricant refill valve

A drive axle

R1, R2 rotation axes

Claims

Patent claims

First rotor (10) of a dual centrifuge with a rotor head (12) and another

Rotary mechanism for at least one rotary unit (22) arranged in the rotor head (12) and comprising a bearing (70) and a rotary head (24) connected to the bearing (70) and rotatable relative to the rotor head (12) the further rotating mechanism is drivable, wherein a recess (16) for the rotary unit (22) is provided, in which this is introduced, and thereby the bearing (70) relative to the rotor head (12) is fixed, characterized in that the rotary unit (22) has a housing (26), in which the bearing (70) is introduced and in which the rotary head (24) engages, and that the housing (26) and the rotary head (24) with bearing (70) form a structural unit , wherein the housing (26) rotatably in the rotor head (12) and releasably supported by this.

2. Rotor according to claim 1, characterized in that the recesses (16) passing through a region of the rotor head (12), the rotary unit used (22) engages through the recess (16), and a lower portion of the housing (26) of

Turning unit (22) exposed from the recess (16) protrudes.

3. Rotor according to claim 2, characterized by a rotationally symmetrical basic shape of the rotor head (12), which describes an envelope, wherein the lower portion of the housing (26) protrudes beyond the envelope.

4. Rotor according to claim 3, characterized in that at least 30%, preferably at least 50% of the height of the housing (26) protrude beyond the envelope.

5. Rotor according to one of claims 2 to 4, characterized in that the lower region of the housing (26) cooling fins (42).

6. Rotor according to one of the preceding claims, characterized in that the rotary unit (22) by a releasable quick release or by a screw connection to the rotor head (12) is firmly connected.

7. Rotor according to one of the preceding claims, characterized in that the housing (26) on its side remote from the cooling fins (42) has a flange (84) which rests against the rotor head (12).

8. Rotor according to one of the preceding claims, characterized in that the recess (16) and the housing (26) are adapted to each other.

9. Rotor according to claim 8, characterized in that the cross-sectional shape of

Housing (26) and the cross-sectional shape of the recess (16) form a rotational security, in particular by a polygonal shape or a cylindrical shape with projections and associated grooves.

10. Rotor according to one of the preceding claims, characterized in that the housing (26) and a housing end (80) with a central bore for a

Rotary axis (25) of the rotary head (24) define a storage space (64) with bearings (70) for the axis of rotation (25).

11. Rotor according to claim 10, characterized in that the storage space (64)

Lubricant-proof is encapsulated to the outside.

12. Rotor according to claim 10 or 11, that the storage space (64) is filled with lubricant,

especially grease, preferably SKF rolling bearing grease LGBB2 / 0.4.

13. Rotor according to claim 11, characterized in that the storage space (64) to 50% of the height of the storage space (64) is filled with lubricant.

14. Rotor according to one of the preceding claims, characterized in that for heat dissipation as large a portion of the surface of the rotary unit (22) with the rotor head (12) is in contact.

Rotary unit (22) for a rotor according to one of the preceding claims.