WO1990011392A1

WO1990011392A1 - Device for removing impurities from a fibre composite on a carding machine

Info

Publication number: WO1990011392A1
Application number: PCT/EP1990/000436
Authority: WO
Inventors: Walter Löffler
Original assignee: Hollingsworth Gmbh
Priority date: 1989-03-17
Filing date: 1990-03-16
Publication date: 1990-10-04
Also published as: EP0387908B1; ES2039977T3; DE3908834A1; JPH04504147A; GR3007220T3; EP0463031A1; EP0387908A1; JP2798810B2; DE59000945D1; CZ278720B6

Abstract

A carding machine consisting of a rotating drum (1) and a taker-in (2) which feeds fibres to the drum is provided with a device for removing impurities from a fibre composite. The device has a first knife blade (20) arranged between the taker-in and a carding element (21), a second knife blade (34) arranged after said carding element (21) and pressure plates (14) located in front of the knife blade. The first knife blade and following carding element (21) constitute a first structural unit (29) which is arranged immediately after the taker-in and the second and each subsequent knife blade (34) together with the following respective carding element (35) forms a second and subsequent structural unit. All structural units are covered over by a common suction housing (40).

Description

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Device for separating impurities from a fiber structure on a card

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The present invention relates to a device for separating impurities from a fiber structure on a card according to the preamble of claim 1.

A carding machine usually has a drum with a larger diameter, sometimes also referred to as a spool, on which a drum with a smaller diameter for feeding fiber material, the so-called licker-in, is arranged. Another drum with a smaller diameter, the so-called customer, is intended to remove the nonwoven fabric formed on the carding drum. Depending on the design, fixed carding covers and / or revolving covers are arranged on the circumference of the carding drum, which work on the fibers in cooperation with the carding drum.

The fiber raw material fed to the card has a large number of impurities such as trash, shell parts, shell nits, that is shell residues with adhering fibers, etc., which should be removed as far as possible in order to produce a high-quality non-woven fabric.

A device for separating impurities from a card according to the preamble of claim 1 has become known from DE-OS 36 44 529. The known device has a hold-down plate which is arranged after the licker-in, followed by a knife at a circumferential distance. The one between the knife and the one Holding plate formed gap is partially spanned by a suction device. After this first knife, several fixed carding elements and then a second hold-down plate are arranged. A further knife is provided at a distance from this hold-down plate. A second suction device spans this second gap formed between the hold-down plate and the knife. The gaps formed between the hold-down plates and the knives cannot be adjusted.

With this known device, a first separation of impurities is carried out by the first cleaning arrangement. The carding with several fixed lids then intensively mixes the material, which means that the impurities still in the material can only be removed with difficulty by the subsequent knife. The overall cleaning effect of this device is therefore unsatisfactory. In addition, the device is structurally very complex.

Another problem relates to the air flow within the device, which is of great importance for an optimal cleaning effect. The carding drum rotates at high speed, which leads to the creation of an air flow in the gaps between the cover plates, the knives and the carding elements. In the known device, it is not possible to influence the air flow in order to optimize the cleaning result depending on the material being processed.

Another cleaning device for a card is known from DE-OS 28 33 413. This known device has several carding plates, which are arranged so that between the adjacent Carding plates each have a gap, the direction of which runs parallel to the dumbbell line of the carding drum. A suction device is provided which has a cover spanning the carding plates, through which contaminants can be suctioned off. With this device, however, it can be problematic to remove the coarse impurities sufficiently from the fiber material. The removal of fine impurities is also not optimal.

The present invention has for its object to provide a device for separating contaminants from a card, which enables both improved coarse separation and improved fine separation of contaminants and which can be made compact and inexpensive.

This object is achieved by the subject matter of claim 1.

In the solution according to the invention, two or more knife blades are provided, each of which is attached to a carding element immediately following it. A hold-down device is provided in front of each knife blade and holds the fiber material down at a predetermined distance from the surface of the carding drum. A gap is provided between the knife blade and the associated holding plate through which the impurities are discharged. The first knife blade is located directly behind the licker-in. In this area, the coarse impurities, such as. B. shells, etc. can be easily removed, because at this point they are still easy to loosen from the not yet carded fiber structure and due to their higher specific weight due to the centrifugal force they are carried out more and therefore can be easily separated from the fibers by the knife blade. In the carding element following the first knife, the fibers are subjected to a first carding after the rough separation has taken place. This carding releases fine impurities which also come out behind the following hold-down plate due to the centrifugal force. The subsequent second knife then separates these finer impurities from the fibers.

The second knife is in turn attached to a second carding element, which can be followed by further hold-down plates, knives and carding elements connected thereto. The units are spanned by a suction housing, in which the material separated by the centrifugal force on the knives is collected and removed with a low vacuum.

With the device according to the invention, coarse separation and fine separation are achieved at the same time, which, in addition to the immediately subsequent arrangement of the two structural units behind the licker, is not least due to the fact that the distance between the first hold-down plate and the carding drum is greater than the distance between the second Hold-down plate and carding drum. While the fiber dressing is still relatively thick but roughly fed to the gap delimited by the first knife blade, the fiber dressing is compressed more when the gap delimited by the second knife blade is reached, but has already passed through the first carding element. This promotes fine separation, i.e. the removal of finer dirt particles. The invention lies here

based on the finding that it is also important for the fine excretion that the carding process must not be too advanced, since then the removal of the dirt from the fiber structure becomes increasingly difficult. The negative pressure prevailing in the suction housing or the suction housings can be relatively low; it is not intended to suck the impurities out of the fiber structure, but merely to remove the impurities which pass through the gap due to the centrifugal force.

In those known in the prior art

It is very difficult for cleaning devices to match the action of the cleaning agents and the air flow generated by the rotation of the carding drum. In an advantageous embodiment of the present invention, this problem is solved in that both the distance between the hold-down plates and the surface of the carding drum and the distance between the knife blades and the drum surface can be adjusted, each element being able to be set individually.

As a result, the coarse and fine waste can be optimally coordinated.

According to a further advantageous embodiment of the invention, the knife blade or the hold-down plate can be adjusted along a bevelled support surface in such a way that, when the distance between the hold-down plate and the drum surface, or the knife blade and the drum surface, is reduced, the gap between the hold-down plate and the associated knife blade decreased. This ensures that with a reduction in the distance, the at the same speed Carding drum usually causes an increase in air flow, the discharge area is reduced. An increased discharge of good fibers can thereby be effectively prevented.

According to a further embodiment of the invention, the hold-down plates which are assigned to the second and each further structural unit are each fastened to the preceding structural unit. This measure further improves the already compact design of the device due to the design of the structural units.

Further advantages, features and possible applications of the present invention result from the subclaims and from the following description of an exemplary embodiment with reference to the attached drawing. In it show:

Figure 1 is a schematic sectional view through a card on which he device according to the invention is arranged.

Fig. 2 is an enlarged schematic sectional view of the embodiment of the inventive device according to FIG. 1, and

Fig. 3 in a view similar to Fig. 2 from another exemplary embodiment of the device according to the invention.

1 shows a section through a card on which an embodiment of the cleaning device according to the invention is arranged. The card has a carding drum or reel 1 on which the licker-in 2 is arranged. The licker 2 is preceded by a feed device 3, via which the -? -

Carded fiber material is fed. A pickup 4 is provided on the side of the drum 1 opposite the licker-in 2, via which the processed fiber material is discharged. Between the licker-in 2 and the taker 4 there is a revolving cover 5 of known design. However, it should be noted that the device according to the invention can of course also be used with cards which have other arrangements of fixed lids and revolving lids.

At the contact area between the licker-in 2 and the carding drum 1, a drum cover 10 is provided, which in the exemplary embodiment has a distance a of approximately 1 mm from the surface of the carding drum.

This drum cover 10 is adjoined, without a gap, by an angle bracket 11, which has a smaller angle leg 11a, which is designed concentrically to the carding drum, and a longer angle leg 11b, which extends away from the surface of the carding drum.

The shorter angle leg 11a and the longer angle leg 11b are not necessarily perpendicular to one another. Rather, it is preferable that the angle legs form an angle of less than 90 °, as will be explained in detail later.

On this bracket, a first Niederhal teplatte 12 is attached. The hold-down plate 12 consists of a first surface 13 which rests on the long angle leg 11b of the angle bracket, a second surface 14 which is angled to the surface 13 and which is tangential to the - 2-

Surface of the carding drum runs and a third surface 15, formed at an acute angle thereto, which faces outwards from the surface of the carding drum.

The first hold-down plate 12 is adjustably attached to the angle bracket. This adjustability can, for. B. can be achieved in that in the first surface 13 of the plate (not shown) longitudinal slots are provided, are guided through the corresponding fastening screws that connect the hold-down plate with the angle bracket. The distance b between the second surface 14 and the surface of the carding drum can then be changed as desired by moving the hold-down plate along the longitudinal slots. Since the long leg 11b of the angle 11 is inclined at an acute angle to the tangential plane of the carding drum, the gap to the subsequent knife is also reduced when the distance between the holding-down plate and the surface of the carding drum is reduced.

The distance b between the hold-down plate and the surface of the carding drum 1 is generally in the range of about 1 mm.

The first hold-down plate, seen in the direction of rotation of the carding drum 1, is followed by the knife blade 20 which is fastened to the carding element 21. The carding element 21 has on its side facing the drum a conventional card set 22, which corresponds to the carding mechanism 23, which is arranged on the carding drum 1 itself and, in the illustration according to FIG. 2, is only indicated in part. The distance c between this carding element and the surface of the carding drum is of the order of 0.4 mm. The knife 20 is fastened to the carding element 21 in such a way that the distance between the knife edge 25 and the surface of the carding drum 1 can also be changed. A gap d is formed between the hold-down plate 12 and the knife edge 25, which is approximately 6 mm if the distance e between the knife edge 25 and the surface of the carding drum is of the order of 0.25 mm. By adjusting the height of the knife in relation to the carding drum, the gap width d between the hold-down plate and the knife edge also changes, as stated.

The knife edge and the carding element form a compact structural unit 29, which makes separate attachment of the knife blade superfluous.

On the, seen in circumferential direction of the drum, the back of the carding element 21, a further hold-down plate 30 is arranged. This hold-down plate 30 is designed in exactly the same way as the hold-down plate 12, so that its structure need not be explained further. It should be noted, however, that by fastening the hold-down plate 30 to the carding element 21 an overall very compact structure of the device is achieved. The hold-down device 30 is also adjustable in its distance f from the surface of the carding drum 1.

In order to achieve an optimal combination of coarse waste and fine waste, the distance f between the second hold-down plate 30 and the carding drum is kept smaller than the distance between the hold-down plate 13 and the carding drum. The distance f is advantageously on the order of 0.55 mm. The second hold-down plate 30 is followed by a second one Ka rdierelement 35, on the front side of a second knife blade 34 is adjustably attached. The structure of the carding element 35 and the knife blade 34 are corresponding to the structure of the carding element 21 and the knife blade 20. The second carding element and the second knife blade 34 thus form a second structural unit 39 which is essentially identical to the first structural unit 29.

As with the first assembly, the knife blade is arranged here so that there is a distance g between the knife blade and the hold-down plate which is of the order of 6 mm when the second hold-down plate 30 is at a distance of 0.55 mm from the surface the carding drum is located. The distance h between the knife blade 34 and the drum surface is also approximately 0.25 mm.

The cover of a housing 40, which spans both structural units and both discharge gaps, is fastened to the second carding element 35. The opposite edge 41 of the housing cover 40 is embedded in a recess 42 in the angle bracket 11. The contaminants are removed from the housing 40 with a slight underpressure via the suction pipe 45.

The function of the device according to the invention is now as follows. In the operating state, the carding drum 1 rotates at a predetermined speed and 3 fiber material is fed onto the licker-in 2 via the feeder 3. The supplied fiber material is picked up by the carding drum 1 by means of the carding set 23 and moved around the carding drum in the circumferential direction. A spinning of the good fibers is prevented by the drum cover 10. After the first hold-down plate, which is in the

Distance b of approximately 1 mm from the surface of the carding drum, the first gap d is formed, which is delimited by the holding plate 12 and the first knife 20. The knife edge has a distance c of approximately 0.25 mm and thus presses deep into the fiber material. As a result of this impression of the still largely untangled fiber material, the coarse impurities are caught by the Hesser and are thrown outwards due to the centrifugal force. This first knife blade is then followed by the first carding element, in which the fibers are carded for the first time. This first carding removes the remaining impurities. The following hold-down plate has a distance f of approximately 0.5 mm from the surface of the carding drum. The gap g formed between the hold-down plate and the second knife 34 is approximately as wide as the first gap d. The knife blade is also pressed into the fiber material.

Due to the slight carding, the wider gap and the reduction in the distance between the hold-down plate and the carding drum, the fine impurities are conveyed to the outside in this second gap and excreted by the effect of the centrifugal force and the effect of the suction vacuum.

In the device according to the invention, as described above, a combination of a coarse separation in the first gap and a fine separation in the second and possibly subsequent columns takes place. The rough separation is carried out with a gap width that is so small that only a small amount of good material is removed with the coarse impurities. At the second time Gap in which a certain carding of the fibers has already taken place, the gap width is kept so that the fine impurities can be reliably removed to the outside. The construction of the device is kept very simple due to the largely identical structural units and the common suction housing.

3 shows a further exemplary embodiment. The structure and mode of operation of the device shown in FIG. 3 are in principle the same as explained above. The same reference numerals are therefore used for identical and similar components. Only the differences are discussed below.

The suction device here comprises two suction housings 40 'and 40 ", the suction housing 40' being assigned to the structural unit 29 and the suction housing 40" to the structural unit 39. The first suction housing 40 * is formed by a cover 46 fastened on the upper side of the angle piece 11 and on the upper side of the first carding element 21. The cover 46 closes tightly with the upper side of the angle 11 and the upper side of the carding element 21. The second suction housing 40 "is formed by the first carding element 21 and the second carding element 35, which are covered by a second cover 46". 3, the two lids 46 ¹ and 46 "overlap in the region of the first carding element 21. The carding elements 21 and 35 each have the fastening elements for the lids 46 'and 46" at the same point, so that it is possible due to the overlap of the two lids 46 ¹ and 46 "to fasten both lids to the carding elements with common screws 47 or the like. If additional structural units (not shown here) are attached, the creation of a further suction housing is easily possible by another lid connects the second carding element 35 with the following carding element in the manner previously described.

It remains to be added that both suction housings 40 'and 40 "each have their own suction pipe 45' and 45", both of which can be connected to a common vacuum blower.

Claims

- ^ Device for separating impurities from a fiber structure on a card

1. Device for separating impurities from a fiber structure on a card having a rotating carding drum and a carding machine which effects the supply of fibers to the carding drum, with at least two knife blades ⁽ 20, 34), a first (20) between the carding tool ⁽ 2) and a carding element (21) and a second one is arranged behind a carding element (21), further with old plates (12, 30) ending with a gap in front of the knife blades (20, 34) and associated therewith and with at least one suction housing (40; 40 ', 40 ") connected to a suction device, which covers the gap between the holding-down plate (12; 30) and the knife blade (20; 34), characterized in that the first knife blade (20) on the subsequent carding element (21 ) is attached and forms with this a first structural unit (29) that the second knife blade (34) is also attached to a subsequent carding element (35) u nd forms a second structural unit (39) which, with the interposition of the previous second hold-down plate (30), directly adjoins the first structural unit (29), so that the radial distance between the first hold-down plate (12) and the carding drum (1) is greater than the radial distance between the second hold-down plate (34) and the carding drum (1).

2. Device according to claim 1, characterized in that the device further, under Interposition of a further hold-down plate includes units directly adjoining the second structural unit (39).

3. Device according to at least one of claims 1 to 2, characterized in that the distance (b, f) between the Nieder old plates and the card ertrommel is each separately adjustable.

4. The device according to at least one of claims 1 to 3, characterized in that the distance (e, h) between the knife blade and the surface of the carding drum is each separately adjustable.

5. The device according to at least one of claims 1 or 4, characterized in that the hold-down plates ⁽ 12, 30) and / or the knife blades (20, 34) are each adjustably attached to an inclined guide surface, the angular position of the drum is selected so that when the distance between the hold-down plate (12, 30) and the carding drum (1), or between the knife blade (20, 34) and the carding drum (1) changes, the gap width (d, g) between the receiving plate and the knife blade never changes.

6. Device according to one of claims 1 to 5, characterized in that a drum cover (10 ^{) is} arranged between the first hold-down plate (12) and the licker-in (2).

7. The device according to at least one of claims 1 to 6, characterized in that the hold-down plates ⁽ 30) which are assigned to every second and each further structural unit are each attached to the preceding structural unit. - / £ -

8. The device according to at least one of claims 1 to 7, characterized in that the hold-down plate (12) assigned to the first knife (20) is fastened to an angle bracket (11) which is between the licker-in (2) and the knife blade, or is arranged between the drum cover and the knife blade and covers the drum between the licker-in and the hold-down plate, or between the drum cover and the hold-down plate.

9. The device according to at least one of claims 1 to 8, characterized in that the distance (e, h) of the knife edge to the carding drum is approximately 1/4 (0.25) mm.

10. The device according to at least one of claims 1 to 9, characterized in that the distance (b) between the first hold-down plate and the carding drum is approximately 1 mm.

11. The device according to at least one of claims 1 to 10, characterized in that the distance (f) between the second hold-down plate (30) and the surface of the carding drum is approximately 1/2 mm.

12. The device according to at least one of claims 1 to 11, characterized in that the gap width (d) between the first hold-down plate (12) and the knife blade (20) is at least about 5 mm.

13. The device according to at least one of claims 1 to 12, characterized in that the gap width (g) between the second hold-down plate (30) and the second knife blade (34) is at least about 5 mm.

14. The device according to at least one of claims 1 to 13, characterized in that the gap widths (d, g ⁾ between the hold-down plates (12; 30) and the subsequent knife blades (20; 34) are at most 10 mm.

15. The device according to one of claims 1 to 14, characterized in that the suction device comprises a common suction housing (40) which spans a plurality of structural units (29, 39).

16. Device according to one of claims 1 to 15, characterized in that a separate suction housing is provided for each structural unit (29, 39 ⁾ , which has a carding element (21, 35) or the one on the top of the carding drum (1) facing away from it Angle bracket (11) and an adjacent carding element ⁽ 21 ⁾ attached cover (46 ', 46 ").

17. The device according to one of claims 1 to 16, characterized in that the cover (46 ', 46 " ⁾ adjacent suction housing (40', 40") overlap and have common attachment points ⁽ 47) in the overlap area.

18. Device according to one of claims 1 to 17, characterized in that the suction device for each suction housing (40 ', 40 ") has its own suction pipe (45', 45").