DE102004058898B4 - Sieve and sieve element for this - Google Patents

Abstract

Sieve with sieve elements arranged on rotating sieve shafts, each having a central recess for the passage of the corresponding sieve shaft, characterized by the following features:
a) the sieve elements are made of resilient material,
b) at least one screen element are associated with two clamping elements (23, 24), wherein the one clamping element (23) is arranged in the axial direction on one side of the screen element and the other clamping element (24) on the other side of the screen element,
c) the clamping elements (23, 24) belonging to the same sieve element are movable towards one another by connecting means, so that material of the sieve element protrudes in the direction of the sieve shaft between the clamping elements (23, 24) and the inner diameter of the recess narrows.

Description

The The invention relates to a sieve with arranged on rotating screen shafts Sieve elements, each having a central recess for the passage of the corresponding Siebwelle have.

Siebsterne sieve elements are made of rubber, PUR or other elastic material. Several screen stars rotate side by side on a screen shaft, see for example EP 1 080 796 A1 , The screen stars rotate to transport the material to be screened in the conveying direction, while the finer material fraction falls through the screen down. For this purpose, the screen stars need a drive torque. So that the torque is transmitted from the screen shaft to the screen stars, the screen stars are usually positively mounted on screen shafts with, for example, square cross-section.

The Strain on the Siebsternarme (spikes) depends, inter alia, on the material to be screened. In unfavorable cases contains the material to be screened Wire ropes or the like. These can be entangle on the siebstern and tear off a sieve arm.

Is missing a Siebsternarm, takes place at this point a screening with larger grain size. To avoid this, the sieve star must be renewed. This means lost work and high repair costs. The entire wave must be dismantled and the stars must subtracted from. The process is complicated by a high friction between Screen shaft and screen stars. Similarly, the replacement of different types Sieve elements must be offered individually after wear.

One Another disadvantage of the known solutions is the fixed relative arrangement the screen stars on the screen waves. The relative arrangement is inevitably due the (measured in the axial direction) width of the mesh hubs, if necessary in conjunction with spacers or slices. Finally, point the known sieve stars due to the square internal cross-section a relatively thick hub with a correspondingly high cost of materials.

Instead of the sieve stars can, Depending on the application, other screen elements may be provided, such as (circular) disks or polygons. Even if below in individual cases only sieve stars are called other sieve elements made of elastic material find use.

From the DE 696 03 061 T2 is a sorting conveyor with shaft rotating wheels known. The wheels are split formed with a dividing plane along the shaft. The impeller halves are connected by bolts that clamp the respective impeller on the shaft when tightened.

task The present invention is the creation of a particularly good Connection between sieve shaft and sieve elements, in particular at Use of screen shafts with a circular outer cross section.

• a) Die Siebelemente bestehen aus nachgiebigem Material,
• b) mindestens einem Siebelement sind zwei Klemmelemente zugeordnet, wobei das eine Klemmelement in axialer Richtung auf der einen Seite des Siebelements angeordnet ist und das andere Klemmelement auf der anderen Seite des Siebelements,
• c) die zum selben Siebelement gehörenden Klemmelemente sind durch Verbindungsmittel aufeinander zu bewegbar, so dass zwischen den Klemmelementen Material des Siebelements in Richtung auf die Siebwelle hervorquillt und sich der Innendurchmesser der Aussparung verengt.

The sieve according to the invention is characterized by the following features:

• a) The sieve elements are made of resilient material,
• b) at least one screen element are associated with two clamping elements, wherein the one clamping element is arranged in the axial direction on one side of the screen element and the other clamping element on the other side of the screen element,
• c) the clamping elements belonging to the same sieve element are movable toward one another by connecting means, so that material of the sieve element protrudes in the direction of the sieve shaft between the clamping elements and the inner diameter of the recess narrows.

The described effect either reduces an existing game between Sieve elements and screen shaft or generated or enlarged one Friction between sieve elements and sieve shaft. To this effect the Clamping elements on the respective associated sieve elements in the sense a bruise, so that part of the material of each Siebelements - in particular in the area of a sieve hub - after is pressed inwards towards the respective screen shaft. By loosening the clamping elements, the diameter of the recess can be increased again. This facilitates replacement of the sieve elements, as without the said Clamping effect depending on the design less friction, no friction or even a slight clearance between sieve and screen shaft exists. The sieve elements can then be easily removed from the screen shaft or postponed. One The clamping elements per screen element can also be fixed with the screen shaft be connected.

On Reason of fixing the sieve elements on the screen waves by (changeable) Friction is any arrangement of sieve elements in axial Direction achievable. The axial distances between the sieve elements can also easily afterwards changed become. Exactly defined hub widths (dimension in axial direction) or special spacers are expendable. The outer cross sections of the Sieve shafts can have almost any shapes.

According to a further aspect of the invention, the sieve shafts have a circular Au ßenquerschnitt on. Preferably, then, the inner diameter of the recess in the sieve elements is circular. A special orientation of the sieve elements on the screen shafts is then not required. The outer diameter of the screen shaft is matched to the inner diameter of the screen elements (or vice versa), such that with the help of the clamping elements sufficient for the transmission of the drive torque stiction can be built up. Due to the round inner cross section of the sieve elements, the sieve element hubs can be substantially thinner in the radial direction than in screen stars for conventional sieve shafts having a square cross section. Also can be used as Siebwellen simple tubes. The sieve can be designed much lighter overall.

To Another idea of the invention is at least one sieve element associated with two clamping elements, wherein the one clamping element in the axial Direction is arranged on one side of the sieve element and the other clamping element on the other side of the Siebelements. The Clamping elements are pulled together by suitable connecting means or pressed and to press while an annular or at least partially ring-shaped Area of the sieve element together, leaving material of the sieve element protruding towards the screen shaft (between the clamping elements), or the inner cross section of the screen element narrows.

Preferably are the belonging to the same filter element clamping elements suitable connecting means in the axial direction towards each other movable. In particular, guided by both clamping elements screws are provided. Optionally, one of the clamping elements has corresponding threads on.

To Another idea of the invention are rings as clamping elements or other circumferentially of the screening shaft (predominantly) closed forms intended. Instead of circular rings can also modified forms used, such as polygons or the like.

To In another aspect of the invention, the clamping elements have a slightly larger inside cross-section on as the associated sieve elements. This will be a contact the clamping elements avoided with the respective screen shaft.

To In a further aspect of the invention, the clamping elements have at least a contact surface inclined relative to the axial direction and / or clamping direction for a corresponding contact surface contact surface of the respectively assigned screen element, so that when moving of the clamping element in the clamping direction, the contact surface of the Siebelements on the contact surface of the clamping element runs up and evades in the direction of the screen shaft and so at least partially the inner cross section of the screen is reduced. At two on the screen element opposite each other Clamping elements is then on each side of the sieve element at least one contact surface available.

advantageously, the sieve element is in particular formed symmetrically with a Symmetry plane perpendicular to the axis of the associated screening shaft, wherein preferably two identically designed clamping elements on both sides (in the axial direction) of the sieve element are arranged.

To Another aspect of the invention, the sieve element in the radial direction different axial strengths on, namely an axially thinner outdoors and an axially thicker interior. It is in the outdoor area Siebsternarme or a screen disc ring arranged during the Interior represents the Siebelementnabe.

Preferably cover the clamping elements a transition between interior and exterior at least partially. The Siebelementnabe is determined by the respective Clamping element covered and thereby protected. in particular extend the clamping elements annular over the entire The size of the interior, with the exception of the outside area or the connection to the outside area.

To Another aspect of the invention, the sieve element in the circumferential direction at least one interruption, such that the sieve element in the area of the interruption, if necessary after bending over, attachable to the screen shaft. Deviating from a circumferential direction closed form, the screening element on a separation point, so that straightened here the screen element and in the radial direction on the Sieve shaft is attachable. The separation point is in the simplest version as radially directed cut through the hub and - in screening stars - at the same time provided between two sieve arms. An exchange of an individual Siebsterns is so easy.

Preferably the sieve element is formed divided, with in the circumferential direction successive segments. This also makes it possible for individuals Replace sieve elements, without dismantling the associated sieve shaft. Preferably, a screen or screen element is made up of several identical ones Segments formed, in particular of three 120 ° -Segementen, about three each Arms. With break of an arm is enough the replacement of a segment.

After another thought of the inventor The clamping elements stabilize the sieve element in such a way that bending of the same in the region of the interruption and / or a detachment of a segment is prevented. The clamping elements get a double function. On the one hand, a friction torque required for torque transmission is built up by the clamping elements. On the other hand, the sieve element or the individual segments are held together to form a stable body extending around the sieve shaft by the clamping elements. To replace the Siebelements or individual segments only the clamping elements must be solved or removed.

Finally is The invention also relates to a sieve element with one or more the above features, at least with clamping elements for reducing the diameter of the recess for the screen shaft and / or with Holding elements for connecting or holding together sieve elements or sieve element segments. Thus, even for screen elements alone, regardless of the other components a sieve claimed protection.

Further Features of the invention will become apparent from the claims and from the description by the way.

advantageous embodiments The invention will be explained in more detail with reference to drawings. It demonstrate:

1 an exploded view of a sieve star with two clamping elements,

2 a plan view of a sieve with clamping elements,

3 a cross section through the sieves according to 2 wherein the section line AA is perpendicular to the axial direction and at the same time through a central axis of the screen star,

4 a section B of the 3 in approximately three times enlarged representation, namely a sieve arm with adjacent hub area (including the clamping elements),

5 a plan view of an annular clamping element,

6 a cross section through the clamping element according to 5 along the line CC,

7 a plan view of the sievers according to 1 , but without clamping elements,

8th an end view of the sieve star according to 7 .

9 a perspective view of a sieving segment,

10 a plan view of the segment according to 9 .

11 an end view of the segment according to 9 and 10 .

12 a section of a star screen, namely screen waves with screen stars.

A sieve star 20 for a star screen, not shown, has on its outer circumference several, in particular nine arms 21 on. The poor 21 extend from an annular hub 22 outward. This is wider in the axial direction than the arms 21 , Accordingly, there is a wider interior area (hub 22 ) and an axially narrower outer area (arms 21 ) of the sieve star 20 ,

The Siebstern 20 are two clamping elements 23 . 24 assigned. These are each designed in the manner of disc rings and have in the circumferential direction consecutively several, preferably nine holes 25 (Clamping element 23 ) respectively. 26 (Clamping element 24 ) on. Corresponding to this, the hub 22 drilling 27 on, leaving the clamping elements on the hub 22 with aligned holes 25 . 26 and 27 can be attached, in particular by each used (not shown) screws.

The sieve stars 20 are made of rubber, PUR or another elastic material. In contrast, there are the clamping elements 23 . 24 preferably of metal, in particular steel.

The two clamping elements 23 . 24 pull the sievers 20 the hub 22 in the area of the same mechanically together, so that the inner diameter of the hub 22 reduced. As Siebwelle a (not shown) is preferably provided tube whose outer cross-section is slightly smaller than the inner diameter of the hub 22 without mounted clamping elements. After tightening the Siebstern sits with high static friction and circumferentially almost immovable on the screen shaft. There is a frictional connection between screens and screen shaft.

To achieve an optimal clamping effect are shape and dimensions of the clamping elements 23 . 24 on the one hand and the sieving star 20 on the other hand, see, in particular, 3 and 4 , The annular clamping elements 23 . 24 are formed in cross-section substantially L-shaped, each with an annular disc 28 and a radially outward adjoining and transverse thereto, on the sieving stars 20 directed circumferential jetty 29 , In the area of the transition from the annular disk 28 to the jetty 29 is an interior angle formed. This comes at a corresponding paragraph 30 in the area of the transition between hub 22 and poor 21 to lie. There is an end surface 31 of the footbridge 29 on an outer surface 32 the poor 21 at.

The jetty 29 closes at the ring disk 28 radially outward. The jetty 29 opposite faces the annular disc 28 radially inside a slanted bearing surface 33 on, on a parallel thereto bearing surface 34 the hub 22 is applied. The mentioned contact surfaces 33 . 34 are in the axial direction, from the arms 21 starting, to the central axis 35 the sieve star 20 inclined. This will reduce the distance between the two clamping elements 23 . 24 Material of the hub 22 towards the central axis 35 pressed. It finds a narrowing of the inner diameter of the sieve star 20 instead of. At the same time, the hub is through the clamping elements 23 . 24 almost completely covered and protected, except for a narrow strip 36 radially within the contact surface 34 ,

The 9 to 11 refer to a split execution of the sieve star 20 , This consists of three identically formed segments 37 , each extending over 120 °, three holes 27 and three arms 21 exhibit.

The segments are held 37 on the screen shaft through the clamping elements already described above 23 respectively. 24 , In case of wear of a sieve star, for example when tearing off an arm 21 can after loosening the clamping elements 23 . 24 only the sieve star or possibly only the segment in question 37 simply be exchanged.

When assembling or cohesion of the segments 37 on the screen shaft, the above-described construction of the annular clamping elements act 23 . 24 with the jetty 29 and the contact surfaces 33 centering, as well as the paragraph 30 and the contact surfaces 34 at the hub 22 ,

The segments 37 each have two flat contact surfaces (faces) 38 on, which are preferably aligned in the radial direction. Adjacent segments lie with their contact surfaces 38 to each other.

Alternatively, the sieve may consist of a single segment, which is only separated at one point with two abutting contact surfaces, analogous to the above-mentioned contact surfaces 38 , Due to the elasticity of the material of the screen star this can be bent up so far that an attachment to the screen shaft is possible. Secured the sieve is bridged by the separation point holding elements or the above-mentioned clamping elements. The hub of the screen star can be provided in this embodiment, corresponding to the peripheral shape of the screen shaft, circular but also polygonal, for example, a square shaft.

12 shows the arrangement of the screen stars 20 on screen waves 39 , The latter are designed as thin-walled tubes. The screen stars are offset from each other in a known manner and arranged interlocking. Due to the radially narrow hub 22 the individual sieve stars 20 have the screen waves 39 at the same hub outer diameter a significantly larger outer diameter than the conventional square shafts. Correspondingly, the torque from the screen shafts is better 39 transferable to the screening stars.

20

screening star

21

poor

22

hub

23

clamping element

24

clamping element

25

drilling

26

drilling

27

drilling

28

washer

29

web

30

paragraph

31

face

32

outer surface

33

contact surface

34

contact surface

35

central axis

36

strip

37

segment

38

contact area

39

screen shaft

Claims (12)

Sieve with sieve elements arranged on rotating sieve shafts, each having a central recess for the passage of the corresponding sieve shaft, characterized by the following features: a) the sieve elements are made of resilient material, b) at least one sieve element are two clamping elements ( 23 . 24 ), wherein the one clamping element ( 23 ) is arranged in the axial direction on one side of the Siebelements and the other clamping element ( 24 ) on the other side of the screen element, c) the clamping elements belonging to the same screen element ( 23 . 24 ) are movable towards each other by connecting means, so that between the clamping elements ( 23 . 24 ) Material of the sieve element in Direction protrudes to the screen shaft and narrows the inner diameter of the recess. Sieve according to claim 1, characterized in that the screen shafts have a circular outer cross-section. Sieve according to claim 1 or 2, characterized in that as clamping elements ( 23 . 24 ) Clamping rings or other circumferential or circumferentially closed forms are provided. Sieve according to claim 1 or one of the further claims, characterized in that the clamping elements ( 23 . 24 ) have a slightly larger internal cross-section than the associated sieve elements. Sieve according to claim 1 or one of the further claims, characterized in that the clamping elements ( 23 . 24 ) at least one inclined relative to the axial direction and / or clamping direction bearing surface ( 33 ) for a corresponding contact surface ( 34 ) of the respective associated screen element, so that upon movement of the clamping element in the clamping direction, the contact surface ( 33 ) of the sieve element on the contact surface ( 34 ) runs the clamping member and evades in the direction of the screen shaft and so at least partially the inner cross section of the screen element is reduced. Sieve according to claim 1 or one of the further claims, characterized in that the sieve element is symmetrical with a plane of symmetry perpendicular to the axis of the associated screening shaft, and that similarly trained clamping elements on both sides of the Siebelements are arranged. Sieve according to claim 1 or one of the further claims, characterized characterized in that the sieve element in the radial direction different axial strengths has, namely a thinner one outdoors and a thicker interior. Sieve according to claim 7, characterized in that the clamping elements ( 23 . 24 ) at least partially cover a transition between the interior and exterior of the screen element. Sieve according to claim 1 or one of the further claims, characterized in that the sieve element has in its circumferential direction at least one interruption, such that the sieve element in the region of the interruption, optionally after bending thereof, on the Siebwelle ( 39 ) can be plugged. Sieve according to claim 9, characterized in that the clamping elements ( 23 . 24 ) stabilize the sieve element, such that a bending of the same in the region of the interruption and / or a detachment of a segment ( 37 ) is prevented. Sieve according to claim 1 or one of the further claims 2 to 8, characterized in that the sieve element is formed divided, with successive in its circumferential direction segments ( 37 ) and that the segments are held together by holding elements, wherein as holding elements preferably clamping elements ( 23 . 24 ) are provided. Sieve element with a central recess for the passage of a sieve shaft, characterized by the following features: a) the sieve element consists of yielding material, b) the sieve element are two clamping elements ( 23 . 24 ), wherein the one clamping element ( 23 ) is arranged in the axial direction on one side of the Siebelements and the other clamping element ( 24 ) on the other side of the sieve element, c) the two clamping elements ( 23 . 24 ) are movable towards each other by connecting means, so that protrudes between the clamping elements of the material Siebelements in the direction of the screen shaft and the inner diameter of the recess narrows.