CN1646742A - Compacting device for drafting fiber sliver - Google Patents

Abstract

A device for compressing drafted fibre slivers in a compression zone behind a front roller pair of a drafting unit, wherein the compression zone comprises a suction element with a sliding surface with at least one suction gap arranged substantially in the direction of movement of the fibre sliver and a conveyor belt which conveys the fibre sliver over the sliding surface and which is at least partially air-permeable over its surface, characterized by the following features: the conveyor belt (12) leaves the suction element (11), partly encircles a guide roller (13), which is placed at a distance from the suction element and is flexibly arranged transversely on its axis of rotation. The guide roller (13) and the conveyor belt (12) in the enclosed region bear against a drive roller (14), and they are provided with means for generating a defined contact pressure between the guide roller (13) and the drive roller (14).

Description

Compacting device for drafting fiber sliver

The invention relates to a device for compacting a drawn fiber sliver in a compacting area behind a front roller pair of a drafting unit, wherein the compacting area comprises an air extraction element with A sliding surface with at least one suction slit arranged on top in the direction of movement of the fiber sliver, and a conveyor belt which transports the fiber sliver over the sliding surface and at least parts of its surface are Breathable.

This device is known, for example from document no.DE 19903531A1. The suction element has a sliding surface on the same side as the fiber sliver travels, is arched in the direction of fiber travel, and is provided with a suction slot. An air-permeable conveyor belt moves across the sliding surface, transporting the fiber sliver. Below the suction element, the conveyor belt loops around a transfer roller, for part of which is driven by a drive roller over a pair of gears. A pinch roller is pressed from the top against the belt resting on the sliding surface to limit the compacted area on the sliding surface. The disadvantage of this procedure is that this conveyor belt has to have completely contradictory properties in order to fulfill the function of the device. On the one hand, it has to provide the highest possible degree of non-adhesive quality on the side contacting the sliding surface, ie a low coefficient of friction. On the other hand, the same side of the conveyor belt has to have the highest possible coefficient of friction and a low sticking tendency in order to allow a proper transfer by transfer roller force. If the coefficient of friction is not ideally adjusted with other parameters, these parameters may be difficult to achieve and the result will be either insufficient drive movement with a high degree of slippage between the transfer roller and the belt, or the belt moving jerky on the sliding surface, which is the result of too much friction. In both cases, undesired irregularities in the yarn quality are unavoidable. Regardless of this, a satisfactory level of power transmission can only be achieved via the transfer rollers if the conveyor belt is kept very tight. However, this leads to unnecessary wear of the conveyor belt and the sliding surface, and is detrimental to smooth movement of the conveyor belt on the sliding surface.

An alternative known document is no.DE 19924527 A1. In this case, the movement of the conveyor belt is produced by means of a friction drive by means of pressure rollers which limit the compaction area. The drive for the pinch roller is partly transmitted by the upper roller of the front roller pair. In this embodiment the conveyor belt is subject to a high degree of wear. This is due, among other reasons, to the fact that the conveyor belt is in tension around the suction element, sliding it over the fixed suction element by means of pinch rollers, which requires a high degree of contact pressure. Furthermore, the conveyor belt is forced to pass through a sharp corner before reaching the compaction zone equipped with air extraction slots. The conveyor belt is thus under a high degree of tensile stress in the compacted area, which in the long run will lead to elongation. On the other hand, after advancing past the pinch rollers, the conveyor belt is in a "thrust" state, so there is a danger of exceeding the length, which is adjusted in time, possibly extending into the Defective support on the conveyor belt. However, this creates a situation in which air can penetrate laterally between the conveyor belt and the sliding surface and can impair the compaction.

The basic object of the invention is therefore to provide a practical device for drafting fiber sliver compaction in which the drive system for the conveyor belt is guaranteed to be safe, subject to little wear and independent of the tension of the conveyor belt.

This object is solved by means of the invention according to claim 1 , and claims 2 to 12 have further advantages which are notable in part.

The device according to the invention has the advantage over the state of the art in that the drive for the conveyor belt is independent of its tension. The conveyor belt is thus maintained at a tension level which is ideal for the remaining function without any detrimental effect on the transmission of the driving torque. In particular, the sliding pairing between the conveyor belt and the sliding surface on the suction element has no detrimental effect.

The skirt is often positioned precisely on the sliding surface as a result of the tension specified for the skirt and the convex shape of the sliding surface. This means that a constant partial vacuum is achieved and air cannot penetrate the system laterally.

Yet another advantage of the present invention is that no changes to the pressure arms or suspension carriers often used on ring spinning machines are required to carry out the solution provided by the present invention. The additional pinch roller required to be located above the sliding surface is housed in a special upper roller holder, which is supported on the shaft of the front roller above the pressure arm. The upper roll holder can be attached or disassembled in a very simple way without any auxiliary assembly equipment, which means that the ring spinning machine can be used both as a standard machine and as a compacting machine, requiring only minimal Make an effort to reorganize them.

Below the present invention will use an embodiment to illustrate in conjunction with accompanying drawing, wherein:

Fig. 1 is a side view of the device of the present invention, and

Figure 2 is a side view of an air pumping element of the device of the present invention.

Figure 1 shows the outlet area of a drafting element 1, which is used on a ring spinning machine. Three driven lower rollers 2, 3 and 4 are arranged on a shaft (not shown), and three rollers 6, 7 and 8 beside them are contained in a pressure support arm 5 and driven. The lower roller 4 and the upper roller 8 jointly form a front roller pair 9 on the drafting element 1 . The drafting of the fed fiber sliver 10 takes place in the drafting unit 1 up to the front roller pair 9, and this is a well-known process.

The compaction zone with the air extraction element 11 , which is connected to the front roller pair 9 , will be described in detail below. Both the suction element 11 and a guide roller 13 are partially surrounded by an air-permeable conveyor belt 12 . At the portion covered by the conveyor belt 12, a guide roller 13 is pressed against a drive roller 14, which is connected to a motor drive unit (not shown). The drive roll 14 and the lower rolls 2, 3 and 4 are preferably part of a drive shaft extending over several spinning positions or the entire machine length. The pressure of the guide roller 13 against the drive roller 14 is generated using a spring 15, which is connected to a holding element 16, which is connected to the frame of the ring spinning machine. The spring 15 presses against the shaft 19, which is usually on a spinning machine, carries the guide roller 13 for two adjacent spinning points, and is temporarily locked in place using a clip 20 which overlaps the edge 17 of the retaining element 16. position. The shaft 19 is not fixed on a bearing, but simply rests on a catch 18 on the retaining element 16 . This means that the guide roller 13 floats at a right angle to the shaft 19 . Springs 15 engage between every two guide rollers 13 , which are positioned on the shaft 19 so wide that it limits the axial mobility of the guide rollers 13 .

A further spring 21 is connected to the retaining element 16 and is pressed against the conveyor belt 12 to provide the required tension.

A pressure roller 22, which is housed in the upper roller mount 23, presses against the conveyor belt 12, and it moves over the suction element 11. The upper roller mount 23 is again fixed on the shaft 24 of the upper roller 4 of the front roller pair 9, held in the pressure arm 5, and detachable. A spring 25 is supported on the pressure arm 5 to provide the required contact pressure of the pressure roller 22 on the suction element 11 .

The present invention is suitable for a situation where the pinch rollers 22 rest on the conveyor belt 12 with a low effective pressure, approximately 1 to 2 daN in total. This means that it is possible to limit the compaction area; the movement of the conveyor belt 12 over the suction elements is not hindered. The pinch rollers are also coated with a soft coating with a Shore A hardness in the range of 53° to 63°.

The suction element 11 comprises a hollow section, preferably drawn steel section, extending over several, or preferably two, spinning points, and in an advantageous manner using two sealing caps 27 made of plastics. Sealed front sides. A common partial vacuum source (although not shown) is distributed to all the spinning points through a suction opening 26 in the suction element 11 . The connection to the partial vacuum source is via an extraction channel, which is connected to the extraction element 11 by means of a removable rubber pad. One suction slot 28 is provided for each fiber sliver (sliding surface) in the area covered by the conveyor belt 12 . The surface of the suction element 11 is additionally treated, at least in the area surrounding the sliding surface, in order to achieve a low coefficient of friction. In an embodiment manufactured from drawn steel sections, this can be done, for example, using shot peening, or by means of surface modification. If an aluminum extruded section is used instead, the surface can be coated to ensure both the required sliding properties and the necessary surface hardness.

As part of the present invention, the conveyor belt 12 has a low coefficient of friction coating on the side that contacts the sliding surface, and a high coefficient of friction coating on the side that does not contact the sliding surface. When combined with other features of the new invention, the movement of the conveyor belt 12 can be significantly improved. Various disadvantages found on such similar devices can be avoided. The inner side of the conveyor belt 12 is not used for power transmission and can therefore be fitted with good sliding properties. The drive movement is supplied to the conveyor belt 12 which presses the guide roller 13 against the drive roller 14 by means of a vertical force exerted by a spring 15 .

By providing the spring 15 with the correct dimensions, the vertical force for power transmission is sufficiently high, but not too high. This feature prevents permanent wear on the conveyor belt 12.

The device of the invention is designed in such a way that all the elements used for the compacted fiber sliver 10 can be assembled or disassembled at the spinning point without requiring any great effort. This means that it is possible to use both the spinning point in the ordinary way and also the compacted spindle. In order to realize a common drafting unit 1, the upper roller mounting bracket 23 with the pinch roller 22 is removed from the pressure support arm 5, and the spring 15 is released to release the guide roller 13, so that the air suction element 11, the conveyor belt 12 and guide rollers 13 can be easily removed from the spinning point.

Glossary of related terms

1- drafting unit

2- Lower roller

3- Lower roller

4- Lower roller

5- Pressure bracket

6-upper roller

7- Upper roller

8-upper roller

9-Front roller pair

10-fiber sliver

11-Air extraction element

12- Conveyor belt

13- guide roller

14-Drive roller

15-spring

16 - holding element

17-Edge

18-clip

19-axis

20-clip

21-spring

22-Pinch roller

23- Upper roller mounting frame

24-axis

25-spring

26 - extraction opening

27 - sealing cap

28-Exhaust gap

Summary of the invention

1. The present invention relates to a device for compacting a drawn fiber sliver, the compaction is carried out in a compaction zone behind the front roller pair of a drafting unit, wherein the compaction zone comprises an air extraction element, There is a sliding surface with at least one suction slit arranged substantially in the direction of movement of the fiber sliver, and a conveyor belt which transports the fiber sliver over the sliding surface and at least across its surface Parts are breathable.

2.1 The basic object of the invention is therefore to provide a device for compacting drafted fiber slivers in which the drive system for the conveyor belt is guaranteed to be safe, subject to little wear and independent of the tension of the conveyor belt.

2.2 The present invention achieves this task by means of the following steps:

- The conveyor belt (12), leaving the suction element (11), partially encircles a guide roller (13), which is placed at a certain distance from the suction element and is flexibly aligned laterally on its axis of rotation.

- the guide roller (13) presses together with the conveyor belt (12) against a drive roller (14) that rests in the surrounding area, and

- Arranging the means to achieve a defined level of contact pressure between the guide roller (13) and the drive roller (14).

2.3 The invention can be used on spindle spinning machines, especially on ring spinning machines.

3. Abstract Figure - Figure 1

Claims (12)

1. the device used of the fibre sliver compacting of a drawing-off, compacting is carried out in the compacted region of preliminary roller to the back of a drafting unit, wherein compacted region comprises a suction element, have a slidingsurface, have at least one suction slit on it, be arranged in basically on the direction that fibre sliver moves, and a conveyer belt, its transmission fibre sliver is crossed slidingsurface and is that the each several part of crossing its surface is breathed freely at least, it is characterized in that following characteristics:

-conveyer belt (12) leaves suction element (11), and partly around a guide reel (13), roller (13) is placed on and leaves suction element a distance, and conveyer belt (12) is transversely arranged flexibly on the turning cylinder of roller (13),

-guide reel (13) withstand around district and conveyer belt (12) supporting a driven roller (14) and

-device is set, between guide reel (13) and driven roller (14), produce the contact pressure of a regulation.

2. according to the device of claim 1, it is characterized in that the laterally directed holding element of guide reel (13) (16) is gone up and compressed by a spring element (15) and withstands driven roller (14), spring element (15) is fixed in the holding element (16).

3. according to the device of claim 2, it is characterized in that spring element (15) limits the activity of guide reel (13) in the axial direction.

4. according to the device of claim 1, it is characterized in that conveyer belt (12) has the coating of a low-friction coefficient on the side of contact slidingsurface, and the coating of a great friction coefficient is on the side that does not contact slidingsurface.

5. according to the device of claim 1, it is characterized in that suction element (11) comprises a drawn steel section.

6. according to the device of claim 5, it is characterized in that the surface of suction element (11) is to be treated at least, reaches a low coefficient of friction subsequently in the zone of slidingsurface.

7. according to the device of claim 1, it is characterized in that suction element (11) comprises people's aluminium extrusion section.

8. according to the device of claim 7, it is characterized in that the surface of suction element (11) is treated in the slidingsurface zone at least, reach a low coefficient of friction subsequently, a high hardness and a high mar proof.

9. according to the device of each or several in the claim 1 to 8, it is characterized in that suction element (11) is configured as one section, it is opened in two sides, and is sealing cap (27) transverse sealing made with plastics.

10. according to the device of each or several in the claim 1 to 9, it is characterized in that, a hold-down roller (22), it limits compacted region, rests on the conveyer belt (12), and slidingsurface is crossed in guiding, has low effective pressure, and sum is roughly 1 to 2daN.

11. the device according to claim 10 is characterized in that, hold-down roller (22) applies a soft coating, has Durometer A hardness in 53 ° to 63 ° scopes.

12., it is characterized in that the whole parts relevant with compacting fiber sliver (10) are arranged in such a way according to each device in the claim 1 to 11 on drafting unit, drafting unit (1) can be used with a kind of traditional approach.