EP0586641A1

EP0586641A1 - Dirt-separating intake

Info

Publication number: EP0586641A1
Application number: EP93905140A
Authority: EP
Inventors: Jürg Faas; Robert Demuth
Original assignee: Maschinenfabrik Rieter AG
Current assignee: Maschinenfabrik Rieter AG
Priority date: 1992-03-25
Filing date: 1993-03-23
Publication date: 1994-03-16
Also published as: US5448800A; WO1993019232A1

Abstract

La séparation des impuretés à travers un orifice (36) aménagé dans l'enveloppe entourant un cylindre ou un tambour en rotation est augmentée par des rainures (142) ou des fentes de guidage pratiquées dans cette enveloppe. Les rainures ou les fentes de guidage s'étendent dans le sens du mouvement des fibres transportées et débouchent dans l'orifice de séparation.The separation of impurities through an orifice (36) arranged in the casing surrounding a cylinder or a rotating drum is increased by grooves (142) or guide slots formed in this casing. The guide grooves or slots extend in the direction of movement of the transported fibers and open into the separation orifice.

Description

Inlet for dirt removal

The invention relates to a device for separating dirt (foreign particles) and / or fiber fragments and short fibers ("trash") from fiber material which, in the form of a fleece, is guided along an arcuate path, e.g. about the axis of rotation of a roller or drum. The track is delimited by an outer casing, at least one opening being provided in this casing, as a result of which the dirt and / or trash is to be separated.

State of the art

Excretion devices of the aforementioned type are known in many places in the blow room or in the opening of a fiber processing plant, but also in other places in the spinning mill. Examples of this can be found in the following pre-publications:

Country No. Owner Application type

EP 23 597 Trützschler On a rotating

roller

EP 110 017 Rieter on a rotating

roller

EP 250 126 Carding Spec. On the reel of a card DE 33 36 323 Trützschler On the reel of a card US 5 022 121 Hollingsworth On the reel of a card DE 38 25 419 Trützschler On the breeze of a card

DE 39 02 202 Trützschler on the reel of a card or (Fig. 9) on the breeze

DE 39 02 204 Trützschler On a rotating

roller Country No. Owner Application sar

On a rotating roller

Opening roller of a rotor spinning machine On the reel of a card On the reel of a card On the reel of a card

In EP 388 791 (or US Pat. No. 5,031,278) it has now been proposed to provide the casing "upstream" of the opening with a structured surface, which is used in particular to set the fleece in vibration in order to use centrifugal force , which also works on the dirt in the fleece, to better convey the dirt to the surface in order to separate it at the edge of the knife and to remove it by suction. The structuring of the surface can e.g. be in the form of a clothing segment, but can also be formed in the manner of a fish scale or by cordoning or longitudinal grooves or longitudinal waves. The longitudinal grooves or longitudinal shafts extend in the axial direction of the rotating roller i.e. transverse to the direction of movement of the fleece.

The invention:

The aforementioned arrangement with a clothing segment has proven to be extremely effective. Based on a new explanation of the effect of this arrangement, the aim of this invention is to propose derived arrangements which can be used in particular where clothing segments (whether for reasons of cost, maintenance or technology) are undesirable. The invention provides a device for separating dirt and / or trash from fiber material, which is guided in the form of a fleece along an arcuate path, for example around the axis of rotation of a rotating roller or drum. The path of movement is outwardly by a shutter ¬ lung limited ie the outer surface of the web is defined by the inner surface of the casing. However, the formwork has at least one opening, through which dirt and / or trash can be excreted.

Devices according to the invention are characterized in that the casing has at least one guide groove or gap which extends in the direction of movement of the fleece and which opens into the discharge opening.

Normally, an elongated discharge opening extends transversely to the direction of movement of the fleece and a plurality of guide grooves or guide gaps are provided which are arranged parallel to one another.

Between the grooves or gaps, the cladding further provides the nonwoven fabric with an inwardly directed guide surface which counteracts the flying away of the fibers under the influence of the centrifugal force. The guide grooves or guide columns can, however, accommodate dirt particles and / or trash. The arrangement acts selectively on fiber or dirt material and favors the separation of the dirt or trash materials, which is very advantageous for the removal of dirt and trash when the good fibers continue to travel. "Good fibers" are to be understood here as "desired fibers", that is to say the system should possibly be adaptable to the application requirements.

Individual embodiments of the invention are explained in more detail below as examples with reference to the drawings. It shows: 1 schematically shows a card,

2 schematically shows the breeze of a card,

3 schematically shows an opening roller or cleaning roller,

Fig. 4 shows an arrangement according to the prior art

Use in a carding machine or an opening or cleaning machine,

4a shows a detail of the arrangement according to FIG. 4,

5 shows a first variant according to this invention,

6 A, B and E further possible variants,

7 shows an adjustable arrangement, in particular for use on the breeze,

8 shows a further adjustable variant, in particular for use on the breeze,

9 is a schematic representation of a modified design for the card,

10 shows a detail of the embodiment according to FIG. 9,

11 schematically shows a grate arrangement according to our European patent application No. 91 116 934.0,

12 shows a modification according to this invention of the grate bars according to EP 91 116 934.0, and

13 is a diagram for explaining the "geometry of the arrangement. Fig. 1 shows a card as shown in Fig. 1 of EP-A-388 791 (or US-C-5 031 278). The card comprises a reel 20 which is rotatably supported about the axis 22. A beater 24 and a customer 26 work together with the drum. Over a part of its circumference, the Tambour 20 also works together with a revolving cover device 28.

Five formwork elements 30, 32 are provided between the beater 24 and the lid device 28 (in the "pre-carding zone"), four of which elements 30 each provide a guide surface for the tamper 20, which is provided with clothing elements 34. The fifth element 32 covers an opening 36 between two elements 30 and converts this opening 36 into a suction if the element 32 is connected to a vacuum source (not shown). The (elongated) opening 26 extends over the entire working width of the drum 20.

Three further elements 30 and one further element 32 are provided between the lid device 28 and the consumer 26 (in the “postcarding zone”). There are seven elements 30 and a further element 32 between the customer 26 and the beater 24 (in the "sub-carding zone"). The effects of the various drum shuttering elements are explained in more detail below with reference to FIG. 4.

FIG. 2 shows the breeze 24 with other devices working with it, namely a feed roller 40 with a dining table 42 and two garnished shuttering elements 43, 44. Between these latter elements there is an opening 46 (like the opening 36) extends over the entire working width of the machine. The directions of rotation of the various rollers or drums are indicated by arrows in FIGS. 1 and 2. In this case, no further element is provided in order to convert the opening 46 into a suction device. The element 43 subsequently carries, at the opening 46, a guide element 48 which is L-shaped in cross section with a support leg which is fastened to the element 43 and a guide leg which extends from the element 43 in the direction of the element 44.

Fig. 3 shows a garnished roller 50 of a cleaning machine e.g. according to DOS 3 902 204 or DOS 4 018 311. The fiber material to be cleaned (not shown) is fed to the roller 50 by a pair of feed rollers 52. The fiber material is then guided past baffle plates (shuttering plates) 53, 54, an opening 56 being formed between the adjacent plates 53, 54. Aperture 56 can be converted to suction by a vacuum source (not shown).

The guide plate 53 carries a guide element 58 and the guide plate 54 carries a knife 60 which offers the roller a cutting edge 62.

Fig. 4 shows a detail of the arrangement according to Fig. 1 (i.e. according to EP 388 791). The set of the reel 20 is indicated in FIG. 4 with the reference number 21. The clothing of the shuttering element 30A "upstream" from the opening 36 is indicated by the reference symbol 34A and the clothing of the shuttering element 30B "downstream" from the opening 36 by the reference symbol 34B.

The latter set 3 B is of no particular importance here and is not explained in more detail. The clothing 34A, on the other hand, plays an important role and is explained in more detail below with reference to the special illustration of a section 60 (FIG. 4A), the element 30A being viewed in the radial direction from the drum 20 to the outside for the illustration in FIG. 4A . Edge 62 in Fig. 4A is the "leading" edge of element 30A and defines the opening 36. The opposite edge of element 3OB (Fig.4) carries a knockout knife 33 which is well known in the art.

The set 34A (as well as the set 21) consists of wire parts 64 (FIG. 4A) lying next to one another, each wire part 64 comprising a foot part 66 and teeth 68. The foot part 66 is somewhat wider than the teeth 68, so that "alleys" 70 are formed between the rows of teeth.

The effect of the arrangement according to FIGS. 4 and 4A (known from EP 388 791) can now be explained as follows:

The space 72 (FIG. 4) between the drum 20 and the shuttering element 30 forms a "guideway" for the fiber material carried by the tamper. In this web the fiber material is processed by the clothing. The fibers are mostly distributed over the working surface of the drum - but they are subject to centrifugal force due to the rotation of the drum. If a fiber (an elongated structure) tends to move radially outwards, it is pushed back into the clothing 21 by the clothing 34A. A fiber can only enter a "lane" 70 (FIG. 4A) in the following two cases:

I. The fiber is stretched out in the direction of movement and is pushed outwards as a whole by centrifugal force. This is a rather rare event.

II. The fiber is very short and therefore fits into the "alley" 70 (fiber fragment, short fibers).

The situation looks different for a dirt particle because of its different shape. Such a particle, if it is not prevented by the fibers, succeeds easily under centrifugal force into an alley 70 and then follows, for example, a trajectory which is indicated by arrow 80. The particle pushes against the knife 33, namely against a surface thereof, which is directed away from the drum 20. When rebounding, the trajectory of the particle therefore goes into the suction rather than back into the clothing 21. A fiber can be "switched off" by the knife 33 from the fleece transported by the drum 20 if the fiber head protrudes radially outwards than the fiber is led under the knife. As previously indicated, the clothing 34A mostly serves to push the fibers back into the clothing 21, which reduces the loss of good fibers in the suction.

In summary, it can be said that the clothing 34A makes the separation process on the knife 33 more selective, so that mainly dirt parts, fiber fragments and short fibers are eliminated.

It is now important to exploit this effect at most without trimmings. Of great interest is the processing of fiber masses that have not yet reached the degree of opening of the nonwoven fabric on the cardboard reel, e.g. on a cleaning roller 50 (FIG. 3) or on the beater 24 (FIG. 2).

FIG. 5 shows a guide plate 48A, which can serve as a replacement for the known guide plate 48 on the beater 24 (FIG. 2). The carrier leg 82 is unchanged and will not be explained in more detail. However, the guide leg 84 has incisions (gaps) 88 on its free (front) edge 86 which form teeth 90 lying therebetween. The incisions 88 now clear the way out of the fiber guideway for free-standing dirt particles - but the fiber mass is still guided by the teeth 90 along the guideway. Since the fiber mass has not yet been broken down into individual fibers, and the individual fibers are more likely to be in a tangled position, there are individual ones - 9 -

Fibers only limited possibilities to fly away with the dirt particles through the incisions 88, especially if no suction is exerted.

6 shows in FIGS. 6A, 6B and 6C the guide legs of three further variants of the new guide plate 48B, 48C and 48D. The guide leg of the sheet 48B consists of fingers 92 with elongated gaps 94 lying between them. Since the effect is similar to that of the variant according to FIG. 5, the corresponding description is not repeated. The 48C variant looks similar - but the guide leg is provided with grooves 96 instead of gaps. The effect in this case is more like that of the alleys 70 (FIG. 4A).

The variant 48D according to FIG. 6C consists of a rod 97 and pins 98 projecting therefrom with gaps 100 therebetween.

The width of the gaps should be adapted to the fiber material, which is rather problematic when the sheet has to be replaced. Figures 7 and 8 therefore show two adjustable designs. In both cases, the guide element is designed in two parts with a carrier part 110 (FIG. 7), 112 (FIG. 8) and a movable part 114 (FIG. 7), 116 (FIG. 8). The carrier part 110, 112 has fastening means (e.g. screws 118, Fig. 7), with which the guide element can be attached to an adjacent element (e.g. element 43, Fig. 2 or 53, Fig. 3). Each carrier part 110, 112 also has a projection 120 (FIG. 7) or projections 122 (FIG. 8) in order to form a guide for the respective displaceable part 114, 116.

Both the carrier part 110, 112 and the displaceable part 114, 116 comprise a protruding guide plate 124, 126 and each guide plate has incisions 128 and intermediate teeth 130. These incisions and teeth are essentially the same as incisions 88 and teeth 90 (FIG. 5).

The effective width of the incisions 128 can now be changed in that the displaceable part 114, 116 is displaced relative to the respective carrier part 110, 112. The incisions 128 can be "closed" if the teeth 130 of the displaceable part 114, 116 are aligned with the incision 128 of the carrier part 110, 112, in which case the incisions 128 of the carrier part 110, 112 are still "grooves" with respect to the guide surfaces of FIG Represent teeth 130 of the carrier part.

The use of these principles in the card is now explained in more detail with reference to FIGS. 9 and 10. The parts which have already been explained in connection with FIG. 4 and remain unchanged in FIG. 9 are indicated with the same reference symbols in both figures and will not be explained again in connection with FIG. 9.

The element 30A of the prior art design (FIG. 4) is replaced in FIG. 9 by an element 140 with grooves or grooves 142. These grooves 142 extend in the direction of movement of the nonwoven fabric (like the "alleys" 70 of the variant according to FIGS. 4, 4A). FIG. 10 corresponds to the view of FIG. 4A for the variant according to FIG. 9. In FIG. 10, the radially inwardly directed guide surfaces of the element 140 are indicated with the reference number 144.

One effect of the invention is an effective enlargement of the width of the opening 36, provided that it concerns those particles, fiber fragments or short fibers that can penetrate completely into a groove 142. The width of the opening 36 between the leading edge 146 (FIG. 10) of the element 140 and the knife 33 is indicated in Fig. 9 with S1. This width "applies", for example, to a fiber 150 which is held in the nonwoven fabric on the drum (not shown in FIG. 9) - even if the "head" (the front end) of the fiber 150 extends radially outwards, as indicated by dashed lines in FIG. 9.

However, the “width” S2, which also includes the length L of the grooves 142, “applies” to a dirt particle (or a fiber which is not held in the fleece). This is true because the knife 33 extends radially inwards through the lateral surface which contains the guide surfaces 144 of the element 140. By means of the application of this invention it is therefore possible to choose the width Sl narrower and still achieve a predetermined.

Fig. 11 schematically shows a grate according to our as yet unpublished European Patent Application No. 91 116 934.0 (filed October 4, 1991). Roststab¬ modules M are carried by a frame 157 and distributed along the circumference of an opening roller 150. The modules M are each assigned a fiber guidance or / and opening and / or cleaning function (and they are adapted to their respective functions). The modules can be used in a changeable order. Each module M is to be understood as a formwork element in the sense of this invention.

The entire content of EP 91 116 934.0 is included in this application.

FIG. 12 schematically shows a single (arbitrary) grate bar module Mx from the arrangement according to FIG. 11. This module Mx has a separating edge 152, a guide surface 154 and an edge 156 which between a separating opening 158 (FIG. 11) this module Mx and the nearest module or the nearest formwork element (viewed in the direction of flow) limited.

According to this invention, the module Mx is provided with guide grooves 160, which form “depressions” in the guide surface and open into the discharge opening, that is to say they extend to the edge 156.

As the example according to FIGS. 11 and 12 shows, this invention can be integrated very well into applications which are designed to influence the separation process as a whole, be it by radial or tangential displacement or by rotating the formwork element. Even in such cases, it is always desirable to improve the selectivity of the separation process so that "good fibers" are passed on (depending on the requirements) and undesired material is excreted.

13 shows diagrammatically the guideway FB of transported fiber material with a radius of curvature R. The path FB is delimited to the outside at a certain point S by a formwork element V of length "L". A particle that is to be eliminated "tries" to follow the tangential "excretion path" AB, which is made possible by this invention.

This results in the depth "t" of the groove or groove that should be formed in the formwork element V, namely from the ratio of element length: radius of curvature (L: R). Theoretically, the groove could have a depth that increases along the length of the groove. In practice, however, a groove (groove) will normally be formed which has a constant depth over its length, this depth being chosen to be somewhat greater than the “minimum” depth t (FIG. 13). In the embodiment according to FIG. 4, the width of each “alley” 70 is essentially given by the stringing together of standardized wire parts 64. However, this width can be determined by providing a distance between the wire parts or (in the other versions) by designing the guide grooves or guide gaps. As shown in FIG. 5, the width of the guide groove or guide column can change over the length of the groove or column (increase towards the discharge opening).

Typical values for different dimensions of the arrangement are mentioned below as examples.

The length of the grooves or gaps is typically

5 to 50 mm

The width S1 of the opening 36 is typically

5 to 25 mm

The distance between the guide surfaces and the set is:

a cleaning roller 0.5 to 2 mm

the breeze 0.2 to 1 mm and

the drum 0.2 to 0.7 mm

The width of the grooves or gaps at the discharge opening is typically:

a cleaning roller 3 to 20 mm

the breeze 1 to 8 mm

the reel 0.3 to 2 mm.

Claims

1. A device for separating dirt from fiber material which, in the form of a fleece, is guided along an arcuate path, the path being delimited to the outside by a formwork and a separating opening being provided in this formwork, where ¬ to be separated out by the dirt is characterized by the fact that the casing has at least one guide groove or guide gap which extends in the direction of movement of the fleece and which opens into the discharge opening.

2. A device according to claim 1, characterized in that the width of the groove or column is selected such that dirt can penetrate into the groove or column relatively easily, while access at least for fibers that are not parallel to the direction of movement, is relatively difficult.

3. A device according to claim 1 or claim 2, characterized in that the width of the groove or column is adjustable.

4. A device according to one of the preceding claims, characterized in that the discharge opening extends transversely to the direction of movement of the fleece and a plurality of guide grooves or guide gaps extending parallel to one another are present.

5. A device according to claim 4 and claim 3, characterized in that Guide gaps are formed between two elements which can be moved relative to one another in directions transverse to the direction of movement of the fleece.

6. A device according to claim 4 or 4, characterized gekenn¬ characterized in that the gaps are formed between fingers protruding from an edge.

7. A device according to claim 4 or 5, characterized gekenn¬ characterized in that the gaps are formed between teeth protruding from an edge.

8. A device according to one of the preceding claims, characterized in that there is a surface opposite the mouth of the or each groove or column, which is directed away from the nonwoven guide track.

9. A device according to one of the preceding claims, characterized in that the discharge opening is provided on the breeze of a card.

10. A device according to one of claims 1 to 8, characterized in that the discharge opening is provided on a cleaning or opening roller.

11. A device according to claim 9 or 10, characterized in that the element provided with the guiding groove or guiding gap can also be adjusted without influencing the groove (s) or gaps (s) to influence the excretion effect.

12. A device according to claim 10 or 11, characterized in that the separation opening is provided between grate bars.