|Title of Invention||
TOP COMB OF COMBING MACHINE
|Abstract||The invention relates to a top comb (1) of a combing machine with teeth (2), arranged next to each other and fastened onto a support element (3), whereat between each of two neighbouring teeth a free opening (D) is being provided. In order to prevent deposits of waste, fibres in particular in the foot zone (5) of the teeth (2) it is suggest,ed to layout the teeth (2), seen in their longitudinal direction, in at least two differently designed sections (AI, A2), whereat the section (A2) tapering off into the foot zone (5) of the teeth (2) is being formed ,in such a way, that deposit of waste, of fibres in particular, is being prevented in this zone.|
Top comb of a combing machine
The invention relates to a top comb of a combing machine with teeth, arranged next to each other and fastened onto a support element, whereat between each of two neighboring teeth a free opening is being provided.
Such a top comb is for instance disclosed in the DE-A1 195 31 605, the EP-PS 351 443 and the EP-A1 557 698. The arrangement of such a top comb to the nipper aggregate is for instance being described and shown in EP-A1 619 389.
With the combing machine, as is for instance being disclosed in EP-A1 619 389, the tear off procedure of the combed fibre tuft takes place then when the nipper is on the most forward and opened position. At this point the nipper has the shortest distance to the clamping point of the succeeding tear-off roller. The combed lap end protruding from the nipper in this position is being laid onto the fiber sliver end having been returned by way of the reverse movement of the tear-off rollers and thereafter it is being transferred to the clamping point of the tear-off cylinder being initiated by the forward movement of the tear-off roller. By this procedure an overlapping, that is a „soldering" of the two ends takes place. By the further forward movement of the tear-off rollers, the fibres which have not been held back by the lap end or by the nipper aggregate respectively are being drawn off. During the conveying process of the lap end into the clamping point between the tear-off rollers and during the actual tear-off procedure the lap end is moved in-between the needles or teeth respectively, of the top comb, which is being fastened to the nipper aggregate. The fibres being drawn off by the tear-off rollers are being drawn through the needle lines of the top comb, whereby in particular naps, trash particles and other waste is being kept back.
While drawing the fibres through the top comb, short fibres in particular (of up to approximately 12 mm length) can wrap themselves around the tooth foot of the teeth of the top comb, and in this position they can form a bandage around the respective tooth. These fibres which can fasten themselves to the tooth are basically so called
„floating fibres" which, during the drawing procedure of the fibred material through the top comb garniture, are not anymore being held by any of the existing clamping lines (tear-off rollers or feeding rollers).
During the succeeding insertion cycle, this bandage is additionally being shifted in the direction of the tooth foot and being compacted thereon.
Said bandages in turn facilitate deposit of further waste in said zone and additionally reduce the free passage space for the combing operation.
In order to remove such deposits and to maintain sufficient operation of the top comb, special cleaning devices have been suggested, which through pneumatic or mechanic means initiate a continuous or discontinuous cleaning of the top comb.
Such cleaning devices are for instance known from the EP-PS 351 443, the EP-PS 531 740, the DE-AS 23 20 200 and the DE-A1 38 15 896.
These special device for cleaning the top comb, however, require additional equipment, some of which are costly and which themselves are also prone to waste accumulation.
It is the object of the invention to design the top comb, or the teeth of the top comb respectively, in such a way that a deposit, in particular of short fibres on the teeth can as far as possible be avoided.
Said task is being solved according to the characteristic part of the claim 1. With the suggested design of the teeth it is possible to form a first section of the teeth in such a way, in order to optimally suit said teeth for the combing operation. The further section of the teeth, which is tapering off into the foot zone of said section can be designed in such a way, that in this zone no deposits, in particular no fibre bandages, may develop. Teeth formed in such a way can for instance be
manufactured as punched parts which in a further step can be embossed in their pointed zone. The expression Jongitudinal direction of the teeth" relates to the direction, which extends from the tooth tip to the tooth foot and which is pointing at a right angle towards the conveying direction of the fibre material.
By the specifically suggested design of the rear teeth flank of the teeth and by the respective design of the width of the tooth foot within the second tooth section it is assured, that during the combing process the lap to be combed out is completely drawn into the combing garniture, and that a deposit of short fibres in the foot zone of the teeth is avoided.
The drawing-in of the lap into the combing garniture is being facilitated by the suggested angular position of the rear tooth flank within the first tooth section, while the inclined position of the rear tooth flank within the second tooth section in relation to the respective tooth width within the tooth foot, effects the disentangling of fibre bandages wrapped around the tooth. When shifting the fibre bandage in the direction towards the tooth foot it is being untied due to the enlargement of the tooth width and the respective angular position of the rear tooth flank and it can either fall off or be taken along and removed by the lap drawn through during the following combing procedure.
Furthermore it is being suggested to dimension the width of the tooth foot of the second tooth section larger than 3 mm. A short fibre has a length of up to approximately 12 mm. By choosing a respective width of the tooth foot it is assured that no closed bandage of short fibres can develop around the tooth foot. Thus fibre bandages that have possibly developed within the first tooth section, will untie themselves when being shifted in the direction towards the enlarged tooth foot and are thereby being removed.
For the combing procedure it is suggested that the length of the first section of the teeth, seen at right angle towards the conveying direction, is being made longer than
the length of the second section. Thus the larger part of the tooth length serves for the actual combing process, while the other part will suffice to carry out the cleaning job
Preferably the length of the first tooth section is chosen twice the length of the length of the second tooth section.
The front tooth flank can be made arc shaped or straight. A suitably adapted form allows the top comb to be arranged as close as possible towards the clamping line of the succeeding tear-off roller. It is also possible to provide the rear tooth flank with an arc shape.
Furthermore it is being suggested that at the transition zone from the first to the second tooth section, the tooth width, as seen at a right angle towards the conveying direction, up to the end of the second section increases. Thus the disentangling of fibre bandages that formed in the first tooth section is being facilitated, while that bandage is being shifted further in the direction of the enlarging tooth foot width.
Furthermore the teeth, in particular within their first section can be laid out in such a way, that the fibres are being diverted from the straight conveying direction during their passage through the comb garniture.
Thereby the combing effect can be increased.
In order to achieve this diversion of the fibres from a straight conveying direction, the teeth can be provided with embossed sections within the first tooth section. Such embossing can also serve to create additional air guides for cleaning (see for example DE-PS 39 37 899).
It is also possible to lay out the cross section of the tooth - seen in conveying direction - in such a way, to be able to influence the fibre guidance between the
teeth, which also Influences the combing intensity (see for instance DE-A1 31 46 006).
Further advantages of the invention are being shown and described more closely by way of an exemplified embodiment and the corresponding drawing, wherein show:
Fig. 1 a schematic side view of a top comb at the nipper aggregate,
Fig. 2 an enlarged partial view of the top comb according to figure 1 within the
Fig. 3 a partial side view according to figure 2
Fig. 4 a further exemplified embodiment according to figure 2
Fig. 5 a cross sectional view A - A, according to figure 4
Fig. 6 a further exemplified embodiment of the teeth within the zone of the
section A - A according to figure 4
Fig. 7 a further exemplified embodiment of the teeth within the zone of the
section A - A according to figure 4
Fig. 8 a further exemplified embodiment of the teeth within the zone of the
section A - A according to figure 4
In figure 1 the front part of a nipper aggregate of a coming machine is indicated, whereat the lower nipper knife 10 and the upper nipper knife 11 are shown partly. Within the nipper a feed roller 12 is rotatably supported. The feed roller serves for the intermittent delivery or the feeding respectively of the lap W. Underneath of the tooth aggregate there is a circular comb 15 being supported rotatably and which is being provided with a comb segment 16. On the nipper base 9 a top comb 3 is being fastened (not shown). It is being referred to the example of EP-A1 354 456, wherein such a fastening is being shown.
The top comb 1 includes a support element which is being indicated in the form of a plate 3. At said support element 3 teeth 2 are being fastened, spaced parallel next to
each other. Between neighboring teeth 2 passages D are being formed by means of spacers being mounted at the end of the teeth (fig. 3).
Such spacers are for instance also shown in EP-PS 557 698. It is also possible to provide the teeth themselves with respective embossed sections, as this is being indicated in DE-A1 196 31 605 and which will later be explained in an example.
Seen in the conveying direction F, a tear-off roller pair 18 is retractably supported behind the top comb 1. The roller pair forms the clamping line KL. The tear-off and soldering procedure has already been described above so that further explanations are not necessary at this point.
Figure 2 shows an enlarged illustration of a tooth 2. Seen from its tip 4 the tooth 2 is being provided with a first section A1 with a length L1, with an inclined rear tooth flank 6, including an obtuse angle a in relation to the conveying direction F. That means the rear tooth flank 6 of the teeth 2 in the first section A1 is inclined in conveying direction F. The succeeding tooth flank portion 6 of the second tooth section A2 extending to the tooth foot 5 over a length L2, is inclined against the conveying direction F and includes an acute angle p with said conveying direction. At the transition from the first section A1 to the second section A2 the tooth width is of a measurement B1, which is smaller than the measurement 82 within the foot zone 5 of the second section A2. In the presented example the tooth width 81, is continuously widened towards the foot zone 5 of the second section A2, in order to accomplish the untying of fibre loops or fibre bandages respectively. It is, however, also possible to provide a step by step increase of the tooth width 81.
As can be seen from figure 3, the single teeth 2 (they could also be needles) are attached at parallel spaces to each other and form free passages D by means of the spacers 20 for the fibre material W to be combed. In order to facilitate the engagement of the teeth 2 into the fibre material W, the teeth 2 of the first section A1
up to the toot tip 4 are formed conical, whereby the passages D within the zone of the tooth tip 4 is larger. Thereby a deposit of waste within this zone of the tooth tip 4 is also being reduced.
As is indicated schematically, the teeth 2 are welded or glued to a support element 3. To fasten the teeth 2 in parallel alignment, in particular during manufacturing of the top comb 1, spacers 20 are being provided.
At their front tooth flank 8 the teeth 2 have a circular arc profile. Thus it is possible to place the top comb 1 as close as possible to the clamping line KL of the following pair of tear-off rollers 18, whereby it is also made possible to maintain a short distance between the clamping line KS of the feeding roller 12 and the clamping line Clothe tear-off roller 18.
It is also possible to vary the layout of the teeth 2 over the width of the top comb 1 -whereat in particular within the border zones 2 the teeth may be formed differently, in order to consider known fibre problems of the lap W to be processed at the border zone. For this aspect it is referred to the content of DE-OS 197 36 582 in which such problems are being described.
It is also possible to provided several rows of teeth 2, as this is for instance disclosed with figure 2 of DE OS 195 31 605.
Furthermore the teeth 2 could be provided with more than two different sections (A1,A2).
In a further exemplified embodiment of figure 4 a tooth form is being shown, whereat the front tooth flank 8 is being provided with a straight edge. The rear tooth flank 6 is in the same way as described in the example of figure 2, being provided with inclined straight edges in the respective tooth section A1, A2, that is with an angle a or p
respectively in relation to the conveying direction F. The teeth 2 in the first tooth section A1 are being provided with an embossed section 22, which is illustrated somewhat larger in the cross section A - A of figure 5.
These embossing serve for the diversion of the fibre from a straight conveying direction F in order to intensify the combing.
Such embossings could also be extended into the zone of the tooth foot in order to generate an air flow for additional blowing out the spaces between the teeth.
Figure 6 shows a cross section view A - A of a further exemplified embodiment, whereat the rear tooth flank 6 is of a smaller width than the front tooth flank 8. Figure 7 shows a further variant according to figure 6 whereat the width of the tooth flank 6 or 8 respectively, are dimensioned in opposite relation. Depending on the case of application, one or the other embodiment will be of advantage for an optimal combing function. Figure 8 shows still a further variant in cross sectional view A - A, whereat the teeth, at least within the first tooth section A1 are arranged at an angle y slanted to the conveying direction F. Said embodiment also increases the combing effect.
With the suggested embodiment it is possible, merely by the suitable design of the tooth form, to keep the top comb clean without the need of installing additional cleaning devices. With the corresponding formation of the teeth, however, also existing cleaning devices can be facilitated in their effectiveness.
1. Top comb (1) of a combing machine with teeth (2) arranged next to each other and fastened onto a support element (3), whereat between each of two neighbouring teeth a free opening (D) is being provided, characterised in that the teeth (2) seen in their longitudinal direction (L) are being provided with at least two different sections (A1 ,A2), whereat the section (A2) tapering off into the foot zone (5) of the teeth (2) is being laid out in such a way, that deposits of waste, in particular of fibres, are prevented in this zone.
2. Top comb (1) according to claim 1, characterised in that the first section (A1) of the teeth (2) starting from their tooth tip (4) in relation to the conveying direction (F) of the fibre material (W) being led through the top comb (1), is being provided with a rear tooth flank (6), which is at least partially inclined in conveying direction and in that the rear tooth flank (6) of the thereon following second section (A2) is at least partially inclined towards the conveying direction and in that seen at right angle from the conveying direction, the width (B1) of the teeth (2) at the transition zone from the first to the second section is at least 20 % smaller than the width (B2) of the opposing end (5) of the second section (A2).
3. Top comb according to claim 1 or 2 characterised in that the width (B2) of the second section (A2) within the tooth foot zone (5) is larger than 2 mm.
4. Top comb according to one of the claims 1 to 3 characterised in that the
length (L1) of the first section (A1) of the teeth seen in longitudinal direction (L) of the teeth (2) is larger than the length (L2) of the second section (A2).
5. Top comb according to claim 4, characterised in that the length of the first
section (A1) is at least twice as long as the length of the second section (A2).
6. Top comb according to one of the claims 1 to 5, characterised in that the
tooth flanks (6,8) of the teeth (2) are being formed arc shaped and / or straight.
7. Top comb according to one of the claims 1 to 6, characterised in that the tooth width (B1) at the transition zone from the first to the second tooth section, seen at right angle towards the conveying direction (F), increases up toward the end (5) of the second section (A2).
8. Top comb according to one of the claims 1 to 7 characterised in that the teeth (2) at least within the first section (A1) are being aligned or formed in such a way, that the fibres during their passage between the teeth (2), are at least being partially diverted from a straight conveying direction (F).
9. Top comb according to claim 8, characterised in that the teeth (2) are being provided with embossed portions (22).
10. Top comb of a combing machine substantially as herein described with reference to the accompanying drawings.
|Indian Patent Application Number||565/MAS/2000|
|PG Journal Number||05/2007|
|Date of Filing||21-Jul-2000|
|Name of Patentee||M/S. MASCHINENFABRIK RIETER AG|
|Applicant Address||KLOSTERSTRASSE 20, CH-8406 WINTERTHUR|
|PCT International Classification Number||D01G 19/10|
|PCT International Application Number||N/A|
|PCT International Filing date|