CN111850750A

CN111850750A - Leather collar drafting device

Info

Publication number: CN111850750A
Application number: CN202010332111.8A
Authority: CN
Inventors: K·冈瑟; P·切费尔斯; C·赛沙伊尔; 拉尔夫·西韦特
Original assignee: Zhuolang Intelligent Technology Co Ltd
Current assignee: Zhuolang Intelligent Technology Co Ltd
Priority date: 2019-04-26
Filing date: 2020-04-24
Publication date: 2020-10-30
Also published as: JP2020183607A; EP3730681A1; BR102020008137A2; MX2020004275A; DE102019110881A1; US20200340148A1

Abstract

The invention relates to a apron drafting device for spinning machines, in particular for rotor spinning machines, having a lower apron guided by a drivable lower roller, which is supported in the region of a drafting zone, in particular a main drafting zone, by a sliding part of an apron bridge. In order to provide a apron drafting device which ensures reliable lower apron guidance while maintaining high drive output, the apron bridge has a guide for guiding the lower apron, said guide having a guide means for laterally guiding the lower apron surrounding the apron bridge.

Description

Leather collar drafting device

Technical Field

The invention relates to a apron drafting device for spinning machines, in particular for rotor spinning machines, having a lower apron guided by a drivable lower roller, which is supported in a drafting zone, in particular a main drafting zone, by a sliding part of a apron bridge (Riemchenbrucke).

Background

Various embodiments of drafting devices for spinning machines are known from the prior art. They are used to draw or draft a sliver of fiber, thereby causing a transverse reduction of the fiber. During drafting, the fibers must be moved side by side as uniformly as possible to obtain a uniform sliver of fibers, which is a prerequisite for the production of uniform yarns. For drawing the fiber strand, the drawing frame generally has a plurality of roller pairs arranged one behind the other, which clamp the fiber strand passing between them in an abutting arrangement. A roller pair is usually formed by a driven lower roller and an upper pressure roller which bears against the lower roller. The drafting of the fibre sliver is obtained in such a way that the circumferential speed increases between the roller pairs in the transport direction of the fibre sliver determined by the direction of rotation of the roller pairs.

After the fibers of the fiber sliver have lost their binding, in particular in the main drafting zone, in which the fiber sliver is drafted with a large draft value, it is known to design the drafting device as a apron drafting device of the type described above, in which the fiber sliver is guided through the apron between the nip lines of the two drafting roller pairs. In this case, a so-called double apron drafting system is particularly widespread, in which a apron is guided around a first upper roller and a lower roller in each case in the main drafting zone, the apron being deflected by a deflection mechanism from the fibre feed direction into the return direction as far as the second roller pair, so that the fibre sliver is guided between the upper apron and the lower apron.

In general, a apron in the form of an endless belt is guided at least around a lower drivable roller, a steering mechanism and a tensioning device, which tightens the lower apron to the pretensioning force required for operation. The lower apron can be driven by a drivable lower roll, wherein the transmission of the drive torque from the roll to the apron is generally ensured by a force transmission co-operation with the upper apron or the upper roll.

Important for the yarn quality is the fiber guiding or drawing quality of the fiber sliver, wherein a uniformly spun yarn is obtained by uniformly drawing the fiber sliver. Because of the main drafting in the apron drafting device in the apron guide region, a perfect guide in this region is of considerable significance. EP2034060 has already disclosed securing the guidance by means of a apron tensioning device with a tensioning arm and a loading mechanism. A disadvantage of such a race tensioner is, however, that it results in a loss of drive power.

Disclosure of Invention

The invention is based on the object of providing a apron drafting device in which a reliable guidance of the lower apron is ensured while maintaining a high drive output.

The invention accomplishes this task by means of a apron drafting device.

The apron drafting system according to the invention is characterized in that the apron bridge has a guide for guiding the lower apron, the guide having a guide means for laterally guiding the lower apron around the apron bridge.

The lower apron guided around the drivable lower roller is supported by an apron bridge which prevents the lower apron from possibly escaping downwards, in particular in the region of the main drafting zone. Furthermore, in the contact region with the upper roller or the upper apron, the lower apron is guided by the sliding section of the apron bridge, which is thus supported on the sliding section in the drafting zone. According to the invention, the apron bridge also has a guide with guide means for laterally guiding the lower apron surrounding the apron bridge. The guide means now ensure that the lower apron remains centered during operation in the region of the offset sliding part, so that a lateral displacement of the lower apron, which would lead to a loss of quality in the thread to be produced, is reliably prevented.

The formation of the guide on the apron bridge allows additional components to be dispensed with, so that the apron drafting system can be produced very simply and inexpensively. In addition, the guide mechanism which guides the lower apron laterally ensures a minimum friction, so that the drive power loss will be excluded or minimized.

The formation of the guide means on the apron bridge also allows the disposal of separate guide means which would complicate the apron drafting arrangement. The apron drafting system according to the invention is therefore distinguished by its simplicity and compactness, which allows a reliable encircling of the lower apron to be ensured even without the lower apron tensioning mechanism, wherein the functional capability is not adversely affected by processing tolerances of the lower apron.

The design of the guide for guiding the lower apron is in principle freely selectable. However, according to a particularly advantageous embodiment of the invention, it is provided that the apron bridge has two guide webs arranged at a distance from one another and laterally surrounding the lower apron in the region of the guide.

The feature of using a guide web here is that it can be formed in a very simple manner on the apron bridge. In this case, they are arranged in any region of the apron bridge in such a way that they laterally surround the lower apron surrounding the apron bridge, thus preventing lateral evasion of the lower apron. The guide webs can be designed, for example, as integral pins formed with the apron bridge, the mutual distance of which corresponds substantially to the width of the encircling lower apron. The guide formed by the guide web can be formed at any point of the apron bridge, wherein it is particularly preferably arranged on the underside of the apron bridge opposite the runner in the region of the return movement of the lower apron.

The design of the guide web is in this case in principle freely selectable. They can thus consist, for example, of special ceramic or plastic materials which have a low coefficient of friction for the surrounding under-apron. However, according to a particularly advantageous embodiment of the invention, it is provided that the guide web has a sliding coating in the contact region with the lower apron. This design of the invention allows the design of a apron bridge with guide webs, independently of any sliding properties, and the guide webs are then adapted to the lower apron by applying a suitable coating on the guide webs.

The guide web can in principle be connected directly to the underside of the apron bridge. However, according to a particularly advantageous embodiment of the invention, it is provided that the guide web is arranged on a stabilizing web which extends over the apron bridge in the region opposite the sliding portion. The use of stabilizing webs additionally increases the strength of the apron bridge and thus ensures very reliably that the encircling lower apron is sufficiently supported. Furthermore, the use of a stabilizing web provides the possibility of very reliable arrangement of the guide web, thereby ensuring reliable operation.

According to a further embodiment of the invention, the drafting device carriage with the lower roller, the lower apron and the apron bridge and/or the apron bridge is adjustable relative to the drafting device carriage in a direction transverse to the circumferential direction of the lower apron.

After the lower apron has to be pressed against the possibly present upper apron or upper roller for the fiber sliver to be drawn, in particular in the region of the main drawing zone, friction-induced wear occurs at the surface that comes into contact with the fiber sliver. As the wear increases, the quality of the spun yarn is increasingly adversely affected, and in this case, in particular in the case of vertical drafting devices, serious disadvantages occur, so that the apron must be replaced frequently.

The possible manner for adjusting the apron bridge in the transverse direction of the circumferential direction of the lower apron according to the previous development of the invention allows the lower apron to be traversed in the transverse direction of the running direction of the sliver. The traversing leads to an even wear of the lower apron surface and thus ensures a consistently high finished yarn quality over a long period of use of the lower apron in relation to a non-adjustable lower apron.

When the apron bridge is adjusted relative to the drawing frame carriage carrying it, the apron bridge is correspondingly mounted movably on the drawing frame carriage, on which in particular the lower roller and the lower apron are mounted. The adjustment of the apron bridge transversely to the direction of displacement of the fiber sliver can also be achieved in that the entire drafting device carriage is mounted adjustably transversely to the direction of displacement of the fiber sliver on the apron drafting device.

Furthermore, by traversing the belt bridges, a Nitschel effect can be caused on the fiber strands, whereby the crack resistance of the roving and of the yarn is positively influenced after the filaments in the roving are in a denser and less ordered position so that the contact area increases and correspondingly the tensile strength of the roving is also increased.

For the adjustment of the apron bridge guide for the lateral adjustment of the lower apron by the guide, the apron bridge and/or the drafting device carriage of the entire drafting device can be adjusted relative to the drafting device carriage transversely to the direction of travel of the fibre sliver. In this case, according to an advantageous development of the invention, it is provided that the apron bridge and/or the drafting device carriage is connected to an actuating drive for actuating the apron bridge and/or the drafting device carriage in a direction transverse to the apron direction relative to the drafting device carriage.

The adjustment of the apron bridge relative to the drafting device carriage or the drafting device carriage relative to the apron drafting device can thus be carried out in a comfortable manner by adjusting the drive mechanism, so that the lower apron is thereby moved back and forth laterally by the displacement of the guide. The use of a regulating drive allows the traversing speed, which is important for the process quality, to be optimally adapted to the fiber sliver to be drawn. Excessive traversing speeds, which lead to a reduction in the strength of the roving, can thus be avoided in a reliable manner, wherein, by adjusting the drive, in addition to the traversing speed, a traversing width, which is also important for the process quality, can also be reliably determined.

The adjusting drive therefore allows an optimum adjustment of the traverse width and the traverse speed, so that no mass loss occurs in the roving, but at the same time the lower apron wear is significantly reduced compared to when no traverse is performed.

Furthermore, according to a particularly advantageous embodiment of the invention, it is provided that the adjusting drive is connected to a control device for determining an adjustment of the drafting system carriage and/or of the apron bridge, in particular for determining an adjustment length and an adjustment frequency.

Drawings

An embodiment of the invention is described below with reference to the accompanying drawings, which show:

fig. 1 shows a perspective view of a roller pair assembly of a apron drafting device according to an embodiment;

fig. 2 shows a perspective view of a drafting device carriage of the apron drafting device of fig. 1 according to an embodiment; and

fig. 3 shows a perspective view of a apron bridge of the drafting device carriage of fig. 2.

List of reference numerals

1 roller pair assembly

3 input roller

4 first draft roller

5 second draft roller

6 output roller

8a first drawing device carriage (for input roller)

8b second drawing device carriage (for first drawing roller)

8c third drafting device carriage (for second drafting roller)

8d fourth drafting device carriage (for output roller)

9 leather collar bridge

10 lower leather collar

11a support

11b support

12 belly strip

13 guide abdominal strip (guiding mechanism)

14 bearing seat

17 main body

18 guide part

22 sliding part

23 first upper roll

24 second upper roll

25 third upper roll

26 fourth upper roll

Detailed Description

Fig. 1 shows a perspective view of a roller pair arrangement 1 of a apron drafting arrangement which can be assigned to a spinning station of a textile machine, not shown here, and which can be fastened to the textile machine. The roller pair arrangement 1 has four first to fourth

upper rollers

23, 24, 25, 26, which are not shown here and are arranged one behind the other in the direction of movement of the fiber sliver passing through the roller pair arrangement 1 and are opposite the respective drivable first to fourth

lower rollers

3, 4, 5, 6. The feed roller 3 which comes into contact with the fibre sliver first belongs to the first to fourth

lower rollers

3, 4, 5, 6, which can be driven by a roller drive and is the first lower roller of the roller pair assembly 1. The feed roller 3 may be mounted on the first draft device carriage 8a together with a roller drive mechanism.

Downstream of the feed roller 3 in the fiber sliver displacement direction, a first drafting roller 4 is arranged, which is mounted on a second drafting device carriage 8 b. In the fiber sliver moving direction, the second draft roller 5 is in contact with the draft roller 4, and the second draft roller is mounted on the third draft device carriage 8 c. The first drawing roller 4 and the second drawing roller 5 can each be connected to their own roller drive, which can also be arranged on the respective second drawing device carriage 8b or third drawing device carriage 8 c.

The second drawing roller 5 does not directly contact the fiber sliver to be drawn, but has a lower apron 10 which surrounds the drawing roller 5 and is in contact with the fiber sliver. The lower apron 10 is designed as an endless belt and also surrounds, next to the second drafting roller 5, an apron bridge 9 which is arranged on

supports

11a, 11b of the third drafting device carriage 8c, wherein the

supports

11a, 11b are arranged on a body 17. In the region of the third drafting device carriage 8c, the lower apron 10 abuts against a sliding portion 22 of the apron bridge 9 facing the lower apron 10. The lower apron 10 is supported by the sliding portion 22 so that the lower apron 10 cannot escape toward the third draft device carriage 8c (see fig. 2 and 3).

On the side opposite the sliding portion 22, the apron bridge 9 has two guide webs 13 which project at a distance from one another from the bottom and form guide portions 18, the guide webs serving as guide means for the lower apron 10, which webs laterally bear against the lower apron 10, in this case being connected to webs 12 which are arranged on the bottom in the direction of the longitudinal axis of the apron bridge 9 and which webs stabilize the apron bridge 9.

The apron bridge 9 is itself mounted movably on the support 11a and in the receptacle 14 of the support 11b, so that it can be adjusted transversely to the direction of movement of the fibers or of the lower apron 10 by means of an adjusting drive, not shown here, for the apron bridge 9. The traversing of the lower apron 10 can thus be effected by the guide web 13 abutting the lower apron 10, wherein the traversing speed and the traversing width are determined by a control device, not shown here and connected to the actuating drive.

The fiber sliver drafted in the roller pair arrangement 1 passes through the delivery roller 6, which is mounted on the fourth drafting device carriage 8d, into the spinning device, not shown here, connected to the drafting device 1. The arrangement of the first to fourth

drafting device carriages

8a, 8b, 8c, 8d can be carried out on a not shown frame of the apron drafting device by means of suitable fixed bearings.

In an embodiment not shown here, provision is made for the third drafting device carriage 8c to be adjusted transversely to the direction of rotation or the direction of displacement of the fiber of the lower apron 10, in addition to or as an alternative to the adjustment of the apron bridge 9 relative to the third drafting device carriage 8 c. In this case, according to a preferred embodiment, the adjustment of the third drawing frame 8c can be carried out by means of an adjustment drive, wherein the adjustment of the third drawing frame 8c can preferably be guided by means of at least one elongated hole and a guide projecting into it. In this way, the slotted holes provided in the drafting device carriage for fine adjustment of the position thereof can be used in a simple manner for traversing the drafting device carriage. The drafting device carriage thus constructed can thus be used selectively for apron drafting devices without or with a traversing of the lower apron. In order to improve the guiding stability, it is particularly preferred to provide more than one elongated hole.

In a further exemplary embodiment, which is not shown here, the lower apron is arranged in the same or similar manner in a so-called pre-drafting zone in the main drafting zone, which is arranged upstream of the main drafting zone in the fibre sliver transport direction and is formed between two roller pairs with mutually different rotational speeds in the fibre sliver transport direction, as an addition or alternative to the arrangement shown. Here too, it is further preferred that the traversing of the lower apron can be carried out in the same or a similar manner.

Claims

1. A apron drafting arrangement for spinning machines, in particular rotor spinning machines, having a lower apron (10) which is guided by a drivable lower roller and which is supported in the region of a drafting zone, in particular a main drafting zone, by a sliding section (22) of an apron bridge (9), is characterized in that the apron bridge (9) has a guide (18) for guiding the lower apron, which guide has a guide mechanism (13) for laterally guiding the lower apron (10) which surrounds the apron bridge (9).

2. Apron drafting device according to claim 1, characterised in that the apron bridge (9) has two guide webs (13) which are arranged at a distance from one another and laterally surround the lower apron (10) in the region of the guide (18).

3. Apron drafting device according to claim 1 or 2, characterized in that the guide web (13) has a sliding coating in the contact area with the lower apron (10).

4. Apron drafting device according to one or more of the preceding claims, characterized in that the guide web (13) is arranged on a stabilizing web (12) arranged in the area of the apron bridge (9) opposite the sliding portion (22).

5. A apron drafting device according to one or more of the preceding claims, characterized in that a drafting device carriage (8c) with the lower roller (5), the lower apron (10) and the apron bridge (9) and/or the apron bridge (9) is adjustable relative to the drafting device carriage (8c) in a direction transverse to the circumferential direction of the lower apron (10).

6. A apron drafting device according to claim 5, characterised in that the apron bridge (9) and/or the drafting device carriage (8c) is connected to an adjusting drive for adjusting the apron bridge (9) and/or the drafting device carriage (8c) relative to the drafting device carriage (8c) transversely to the circumferential direction of the lower apron (10).

7. A apron drafting system according to one or more of the preceding claims, characterized in that the actuating drive is connected to a control device for determining the adjustment of the drafting system carriage (8c) and/or of the apron bridge (9), in particular for determining the adjustment length and the adjustment frequency.