[0001] The invention relates to an extraction roller for mechanically opening fiber bales.
[0002] Extraction rollers are used in so-called bale take-off machines or bale openers to
extract fibers or fiber flocks from pressed fiber bales. For this purpose, one or
more extraction rollers are moved across the fiber bales. Bale openers are also known
from the prior art in which the fiber bales are moved past a stationary extraction
roller.
[0003] Such extraction rollers are fitted with teeth which engage in the fiber bales and
tear or pluck fibers or fiber flocks from the fiber bales due to the rotation of the
extraction roller. The bale take-off machine is located at the beginning of processing
lines in a spinning preparation (blow room) for processing fiber material, for example
cotton or synthetic fibers or mixtures thereof, and has a decisive influence on the
continuity of the sequences within the spinning preparation. In the bale take-off
machine, the fiber material delivered in bales is extracted from the bales by taking
off fiber flocks, and is transferred to a pneumatic transport system. The pneumatic
transport system carries the fiber flocks through pipelines to the downstream cleaning
machines. A grid is normally provided between the extraction roller and the fiber
bales. The teeth of the extraction roller extend through the grid. The grid is thus
used as a retaining element for the fiber bales. As the result of the grid elements
which rest on the surface of the fiber bales, the teeth of the extraction roller are
prevented from pulling oversized or irregular fiber flocks from the fiber bales.
[0004] Many designs of extraction rollers are known from the prior art. For example,
EP 0 058 781 discloses a extraction roller in which the toothed disks are fastened to semicircular
shells. Two of these half-shells in each case enclose the shaft of the extraction
roller, and are fastened to one another in such a way that a press fit results between
the half-shells and the shaft. One disadvantage of the disclosed design of the extraction
roller is the complicated structure of the half-shells, and, due to a press fit, a
detachable fastening of the toothed disks which may come loose, also during operation.
[0005] EP 2 836 630 A1 discloses another embodiment of an extraction roller. The toothed disks have a ring-shaped
design with an elliptically shaped central cutout. The toothed disks are pushed onto
a shaft and rotatably fixedly connected to the shaft. The toothed disks that follow
are each turned relative to one another in such a way that their teeth, viewed in
an axial direction, are not aligned one behind the other. In addition, the toothed
disks are arranged at an angle of inclination with respect to the shaft axis. One
disadvantage of this design is that replacing individual toothed disks is not possible.
It is a frequent occurrence that a tooth breaks off, or the teeth are worn down more
in a particular area than in other areas. However, such signs of wear cannot be easily
dealt with, since it is not possible to either replace individual teeth or to replace
individual toothed disks.
[0006] The object of the invention is to provide an extraction roller that has a simple
design, and that allows easy replacement of individual tooth elements.
[0007] The object is achieved by an extraction roller having the features of the independent
claim.
[0008] To achieve the object, a novel extraction roller for mechanically opening fiber bales
is proposed, having a base body designed as a tube, a roller axis, and fastening elements
situated on the base body along the roller axis. The fastening elements protrude perpendicularly
from a surface of the base body, and each fastening element has at least one through
opening, parallel to the roller axis, for fastening tooth elements. Two tooth elements
in each case, having at least two teeth in each case, are mounted on each fastening
element, the two tooth elements being situated at the particular fastening element,
on opposite sides thereof. The tooth elements are arranged in a circumferential direction
of the base body in such a way that the teeth of the respective tooth elements fastened
to a fastening element are offset relative to one another in the circumferential direction.
[0009] The fastening elements are fastened to the base body by welding or adhesive bonding,
for example. The fastening elements are arranged on the surface of the base body in
the manner of ribs. The fastening elements may be designed as closed rings or as ring
segments. Due to the design of the tooth elements in the form of ring segments, they
may be individually mounted on the fastening elements, independently of the base body,
and if necessary, may also be independently replaced without having to remove the
base body or the entire extraction roller from the machine. It is possible to easily
replace individual tooth segments in the installed state of the extraction roller.
[0010] The fastening elements are advantageously each arranged in pairs, the fastening elements
of one pair being offset by a certain distance in the axial direction with respect
to a pair of fastening elements following in the axial direction. The distance between
the pairs of fastening elements is determined by the clearance width of the grid through
which the tooth elements, held on the fastening elements, extend. The distance between
two pairs of fastening elements is preferably 20 mm to 35 mm, particularly preferably
27 mm. This distance is necessary in order to provide enough space between the tooth
elements of adjacent pairs of fastening elements for a grid bar of the grid situated
below the extraction roller.
[0011] The fastening elements of a pair are advantageously situated on the surface of the
base body, opposite one another in the radial direction. A uniformly distributed load
over the circumference of the base body may thus be achieved, and imbalance of the
extraction roller is avoided due to the arrangement of the fastening elements or tooth
elements.
[0012] The distance between the fastening elements of a pair is preferably 15 mm to 25 mm,
particularly preferably 18 mm. This distance has proven suitable, since the gap between
the grid bars when the teeth extend through results in an optimal size of the flocks
removed from the bales by the extraction roller.
[0013] The through openings provided in the tooth elements for fastening the tooth elements
to the fastening elements are preferably situated in each case at one location on
a tooth. The connection of two teeth may thus be established to form a tooth element
in the form of a narrow web, so that weight may be saved.
[0014] In one preferred embodiment, the fastening elements or the through openings in the
fastening elements in their sequence are turned relative to one another on the base
body in the direction of the roller axis by a certain angle β in the circumferential
direction. The radial turning between two successive teeth is preferably provided
at an angle β of 6 to 36 degrees. This results in a full revolution after a certain
number of teeth. For example, for a turning angle β of 36 degrees, the tenth tooth
element is identical to the first tooth element. The turning angle β is selected as
a function of the number of tooth elements on the overall extraction roller, resulting
in a whole number of helical curves. The individual teeth or tooth elements are particularly
preferably turned relative to one another by an angle β that corresponds to the nth
portion of 360° or a multiple thereof, where n stands for the number of pairs of fastening
elements on the extraction roller in the direction of the roller axis.
[0015] The individual tooth elements situated in succession on the shaft have an identical
design. However, the tooth elements have different radial arrangements in order to
achieve better running characteristics of the extraction roller. As a result, not
all successively arranged teeth engage in the fiber bales at the same time. Due to
the radial turning, a tooth of one tooth element engages in the fiber bales, and only
after the extraction roller has been further rotated does a tooth of a subsequent
tooth element come into engagement. This also results in continuous removal of fibers
from the fiber bales, viewed over the entire length of the extraction roller. In addition,
transmission of vibrations is reduced due to the staggered engagement of the individual
tooth elements. The required number of fastening elements may be limited by mounting
a tooth element in each case on each side of a fastening element (in the direction
of the roller axis).
[0016] The fastening elements advantageously enclose the base body by less than 180 degrees.
This type of design prevents the extraction roller from becoming too heavy. In addition,
it is thus possible for all used fastening elements to have the same design, and for
the offset of the tooth elements, and thus the teeth, to be achieved solely by their
arrangement on the base body.
[0017] Two fastening elements are particularly preferably situated in a shared plane. This
measure also results in a reduction in the number of fastening elements. In addition,
tooth elements or teeth are provided over the entire circumference of the extraction
roller, and therefore teeth do not engage in the fiber bales just at a certain location
of the grid during a partial revolution.
[0018] In each case the tooth elements advantageously have two through holes and the fastening
elements have at least three through holes, the through holes of the fastening elements
being designed as a female thread. It is thus possible to easily screw the tooth elements
to the fastening elements. However, other types of fastening, such as a clip connection,
are also conceivable.
[0019] The fastening elements are preferably welded to the base body. Alternatively, in
a design of the base body as a cast part, integral molding of the fastening elements
is conceivable. It is advantageous for the base body to have a circular cross section.
A cross section in the shape of a polygon would also be conceivable, although a circular
cross section has advantages for simpler balancing.
[0020] The teeth are situated on the outer circumference of the tooth elements. The outer
circumference of the tooth elements has a circular design. A rotationally symmetrical
arrangement of the teeth is thus possible. A tooth element preferably has two teeth.
The teeth on their outer surface are preferably subjected to heat treatment to impart
a certain wear resistance. Tempering or hardening is used as heat treatment. However,
other processes for increasing the wear resistance are also conceivable, such as coating
instead of heat treatment. In some cases, sufficient wear resistance may also be achieved
by appropriately selecting the material to be used for the toothed disks.
[0021] The teeth preferably have an external shape that allows operation of the extraction
roller in both directions. The extraction roller may thus be moved in both directions
across the fiber bales, which may also be removed in both directions.
[0022] A bearing element is advantageously provided at both ends of the extraction roller.
A simple tube may thus be used as the base body. The bearing element may be provided
with a journal that engages in the tube and is welded to the tube. Alternatively,
the tube and the bearing element may be provided with a flange. The flange may in
turn be welded or screwed on. However, the bearing element is preferably provided
with a projection that engages in the base body. This allows precisely fitting positioning
of the bearing element as well as a rotationally symmetrical arrangement of the bearing
element with respect to the base body. The bearing element has a shaft stub via which
the extraction roller may be rotatably held in appropriate bearings.
[0023] Also claimed is a tooth element for use in an extraction roller according to the
above description.
[0024] The invention is explained in greater detail below based on one exemplary embodiment,
with reference to the drawings.
- Figure 1
- shows a schematic perspective illustration of a extraction roller
- Figure 2
- shows a schematic illustration of a partial side view of a extraction roller
- Figure 3
- shows a schematic illustration of an enlarged detail from Figure 2
- Figure 4
- shows a schematic illustration of a view in the direction X in Figure 2
[0025] Figure 1 shows a schematic perspective illustration of an extraction roller 1. The
extraction roller 1 has a roller axis 3, and includes a base body 2, on the surface
8 of which a series of a plurality of first fastening elements 4 and second fastening
elements 5 are arranged in a plane and in concentric adjacent planes. In each case
two tooth elements 9 are mounted on the fastening elements 4 and 5 via screws 12,
wherein the screws 12 engage in through openings 11 formed in the tooth elements 9,
and engage in the fastening elements 4 or 5 via through openings 7 designed as a female
thread. Two tooth elements 9 are mounted in each case on the fastening elements 4
and 5. Each tooth element 9 is fitted with two teeth 10. The fastening elements 4
and 5, and thus also the tooth elements 9, are arranged in the circumferential direction
in an offset sequence in the direction of the roller axis 3. The arrangement of the
teeth 10 has a helical configuration due to the identical design of all tooth elements
9.
[0026] Figure 2 schematically shows a partial side view of the extraction roller 1, having
a roller axis 3 and a base body 2. A bearing element 14, which in the shown embodiment
is welded to the base body 2, is situated on the end of the base body 2. Mutually
offset fastening elements 4 and 5 are provided on the surface 8 of the base body 2
in the circumferential direction. A first fastening element 4 and a second fastening
element 5 in each case form a pair 6. Tooth elements 9 having teeth 10 are in each
case mounted on both sides of the fastening elements 4 and 5, viewed in the direction
of the roller axis 3. The tooth elements 9 are fastened to the fastening elements
4 and 5 via screws 12. The fastening elements 4 and 5 of a pair 6 are spaced apart
by a distance B in the axial direction, and are situated opposite one another on the
surface 8 of the base body 2 in the circumferential direction. The first fastening
element 4 of a pair 6 is situated at a distance A from the second fastening element
5 of a pair 6 that successively follows in the axial direction.
[0027] Figure 3 shows a schematic sectional illustration of an enlarged detail from Figure
2. The figure shows a section of the base body 2, designed as a tube, and a fastening
element 4 that is affixed thereto via a weld 13. The fastening element 4 has a through
opening 7 that is designed as a female thread. The design of the through opening 7
as a female thread allows a tooth element 9 to be fastened from both sides of the
fastening element 4. The tooth element 9 has a tooth 10 on an end opposite from the
surface 8 of the base body 2. In the embodiment shown, the through opening 11 provided
in the tooth element 9 is designed for the use of a countersunk screw.
[0028] Figure 4 shows a schematic illustration of a view in the direction X in Figure 2.
On its surface 8 situated about the roller axis 3, the base body 2 bears the fastening
elements 4 and 5. The fastening elements 4 and 5 are provided with through openings
7 in which the tooth elements 9 are held via the screws 12. The fastening elements
4 and 5 or the pairs of fastening elements 4 and 5, and thus the tooth elements 9,
in their sequence are arranged at a radial turning angle β in the direction of the
roller axis 3. Since all fastening elements 4 and 5 and also the tooth elements 9
have identical designs in each case, turning about the angle β results in an offset
of the teeth 10 of the tooth elements 9 following in succession in the axial direction,
likewise by the angle β.
List of reference symbols
[0029]
- 1
- extraction roller
- 2
- base body
- 3
- roller axis
- 4
- first fastening element
- 5
- second fastening element
- 6
- pair of fastening elements
- 7
- through opening in the fastening element
- 8
- surface of the base body
- 9
- tooth element
- 10
- tooth
- 11
- through opening in the tooth element
- 12
- screw
- 13
- weld
- 14
- bearing element
- A
- distance between two pairs of fastening elements
- B
- distance between the fastening elements of a pair
- β
- turning angle
1. An extraction roller (1) for mechanically opening fiber bales, having a base body
(2) designed as a tube, a roller axis (3), and fastening elements (4, 5) situated
on the base body (2) along the roller axis (3), wherein the fastening elements (4,
5) protrude perpendicularly from a surface (8) of the base body (2), and each fastening
element (4, 5) has at least one through opening (7), parallel to the roller axis (3),
for fastening tooth elements (9), characterized in that two tooth elements (9) in each case, having at least two teeth (10) in each case,
are mounted on each fastening element (4, 5), the two tooth elements (9) being situated
at the particular fastening element (4, 5) on opposite sides thereof, and the tooth
elements (9) are arranged in a circumferential direction of the base body (2) in such
a way that the teeth (10) of the respective tooth elements (9) fastened to a fastening
element (4, 5) are offset relative to one another in the circumferential direction.
2. The extraction roller (1) according to Claim 1, characterized in that the fastening elements (4, 5) are each arranged in pairs, the fastening elements
(4, 5) of one pair (6) being offset by a certain distance (A) in the axial direction
with respect to a pair (6) of fastening elements (4, 5) following in the axial direction.
3. The extraction roller (1) according to Claim 2, characterized in that a distance (A) between two pairs (6) of fastening elements (4, 5) is 20 mm to 35
mm.
4. The extraction roller (1) according to Claim 2 or 3, characterized in that the fastening elements (4, 5) of a pair (6) are situated on the surface (8) of the
base body (2), opposite one another in the radial direction.
5. The extraction roller (1) according to one of Claims 2 to 4, characterized in that the distance (B) between a first fastening element (4) and a second fastening element
(5) of a pair (6) is 15 mm to 25 mm.
6. The extraction roller (1) according to one of the preceding claims, characterized in that the fastening elements (4, 5) or the through openings (7) in the fastening elements
(4, 5) in their sequence are turned relative to one another on the base body in the
direction of the roller axis (3) by a certain angle (β) in the circumferential direction
(2).
7. The extraction roller (1) according to one of the preceding claims, characterized in that the fastening elements (4, 5) enclose the base body (2) by less than 180 degrees.
8. The extraction roller (1) according to one of the preceding claims, characterized in that the tooth elements (9) in each case have two through holes (11) and the fastening
elements have at least three through holes (4, 5), the through holes (7) of the fastening
elements (4, 5) being designed as a female thread.
9. The extraction roller (1) according to one of the preceding claims, characterized in that the fastening elements (4, 5) are welded to the base body (2).
10. The extraction roller (1) according to one of the preceding claims, characterized in that the base body (2) has a circular cross section.
11. The extraction roller (1) according to one of the preceding claims, characterized in that the teeth (10) on their outer surface are subjected to heat treatment.
12. The extraction roller (1) according to one of the preceding claims, characterized in that the teeth (10) have an external shape that allows operation in both directions for
opening the fiber bales with the extraction roller (1).
13. Tooth elements (4) [sic; (9)] for use in a extraction roller (1) according to one
of Claims 1 to 12.