GB2228951A

GB2228951A - Producing a staple fibre yarn

Info

Publication number: GB2228951A
Application number: GB9004479A
Authority: GB
Inventors: Manfred Pueschmann; Volker Roland; Peter Voidel
Original assignee: Kombinat Textima VEB
Current assignee: Kombinat Textima VEB
Priority date: 1989-03-01
Filing date: 1990-02-28
Publication date: 1990-09-12
Also published as: IT1244044B; JPH03199430A; DD285517A7; IT9047641A0; DE4000107A1; GB9004479D0; IT9047641A1

Description

1 A METHOD OF PRODUCING A STABLE FIBRE YARN The present invention relates

to a method of producing a stable fibre yarn by twisting fibre or thread.

It is known to feed fibre material drawn from a drawing frame onto one of two centrifugal spindles disposed under the drawing frame. The second centrifugal spindle is already filled with partially twisted thread material. Thread is pulled off from the second spindle and wound onto spools to impart the rest of the twist (see DD 22 772). It is likewise known simultaneously to feed fibre material into two centrifugal spindles while the thread material is drawn off from two filled centrifugal spindles and is wound onto spools (DE-OS 2 229 263).

The disadvantage with both known techniques is that there is only one delivery point on the drawing frame. Therefore, on its way to the relevant centrifugal spindle, the drawn fibre material must be deflected resulting in an accumulation of rotation and a substantial risk of thread breakage.

To overcome shiarp deflection of the drawn fibre material the centrifugal spindles can be mounted on a geared unit by which the relevant centrifugal spindle is transported on a circular path centrally in relation to 2 the drawing frame (DD 250 961). Complicated and costly mechanisms are needed, however.

All the known methods and apparatuses in this field suffer from the common disadvantage that only one delivery point is available for both centrifugal spindles. Fibre material can then only be fed to the second centrifugal spindle when the first centrifugal spindle is full. This means that even in a case where the spooling rate is greater than the rate of delivery from the drawing frame or where the time for the spooling phase plus a subsequent preparation phase for the next delivery phase is shorter than the time for the delivery phase, fibre material cannot be fed to the centrifugal spindle directly upon completion of the preparation phase since at this point in time fibre material is still being delivered to the other centrifugal spindle. Thus, greater shut-down times or dead times in the spooling process result which thus adversely affects production levels.

A generally object of the invention is to provide an improved method which enables fibre material to be drawn from several delivery points onto two centrifugal spindles associated with a spooling arrangement.

According to the invention there is provided a method of producing a stable fibre yarn where the twist is imparted in two stages by means of a drawing frame cooperating with two centrifugal spindles and a spooling i t 1, 3 arrangement; said method comprising feeding fibre material to each centrifugal spindle from a separate delivery point, interrupting the feed after each centrifugal spindle is-filled with partially twisted thread material to permit the material to be taken up by the spooling arrangement and given a final twist and controlling the working sequence so that at some stage material is supplied simultaneously to both centrifugal spindles.

Preferably, th- i--rking sequence for each spindle comprises a spooling phase when material is taken up by the spooling arrangement and a delivery phase when the material is taken up by the spindle and between the spooling phase and the delivery phase, there is a preparatory phase during the course of which the spindle can be cleaned and/or prepared for the next delivery phase.

The invention is explained in greater detail hereinafter with reference to the following description and the accompanying drawings, in which:

Figure 1 is a simplified plan view of part of a spinning machine with a drawing frame, two centrifugal spindles and a spooling arrangement operating in accordance with the invention; and Figures 2a, 2b and 2c are representations of the time related patterns of the individual working phases of 4 the two centrifugal spindles.

The working zone of the spinning machine shown in Figure 1 consists essentially of a drawing frame 1, two centrifugal spindles 6; 7 and a spooling arrangement 8. The drawing frame 1 has fibre material stop means 2, 3 at the intake and outlets or delivery points 4; 5. The centrifugal spindles 6, 7 are disposed centrally of the delivery points 4, 5 and are only indicated with reference to their mounting and drive.

Separate strands of fibre material 9, 11 are selectively interrupted by the stop means 2, 3. Thus, the fibre material 9 passes through the open fibre material stop means 2, is drawn in the drawing frame 1 and passes from the delivery point 4, without being deflected in any way, to the centrifugal spindle 6. The fibre material 9 obtains part of its twist in this manner. Partially twisted thread material 10 is drawn from the other centrifugal spindle 7 and is wound up by the spooling arrangement 9, with the final twist being imparted to the thread material 10. Supply of the fibre material 11 to the delivery point 5 is interrupted during this time by the fibre material stop means 3. Interruption of the delivery of fibre material 9; 11 may also be effected by other means, e.g. by stopping parts of the drawing frame 1. Upon completion of an appropriate preparation phase, the feed of fibre material 1 11 11 is opened up again by opening the fibre material stop means 3, the delivery phase to the centrifugal spindle 7 is initiated and the afore described process takes place in the reversed sequence. The working sequence can be considered as a preparatory phase, a delivery phase and a spooling phase and by incorporating two delivery points 4, 5 as shown the advantages of this invention can be clearly seen in Figures 2a, 2b and 2c.

Figure 2a makes it clear that between the end of the spooling phase of the centrifugal spindle 6 or 7 and the commencement of the spooling phase of the centrifugal spindle 7 or 6, the same amount of time is always available. Figure 2b makes it clear that at the commencement of the spooling phase at the centrifugal spindle 7 almost coincides with the end of the spooling phase at the centrifugal spindle 6. Figure 2c makes it clear that the commencement of the spooling phase at the centrifugal spindle 6 almost coincides with the end of the spooling phase at the centrifugal spindle 7.

In all cases, during a period which is identified as T, fibre material 9, 11 is being supplied to both centrifugal spindles 6, 7. Thus, in a specific unit of time per spooling process, more yarn is produced than on a basis of the delivery rate from the drawing frame 1. In the time which is designated, the preparatory phase, the relevant centrifugal spindle 6, 7 is, upon completion 6 f' I- of a spooling phase, cleaned of any thread material fibre dust or other deposits. Furthermore, during this time, the next spooling phase for the other centrifugal spindle is prepared or started in that the spool change is initiated or, in the event of a plurality of centrifugal fillings being wound onto one spool, the end of a thread present on the spool is joined to the thread coming from the centrifugal spindle during the next spooling phase, or the thread is again attached to the spool. During the preparatory phase, the relevant centrifugal spindle can be stopped.

By operating in this manner stable yarn production can be increased and thread breakages minimised.

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Claims

1. A method of producing a stable fibre yarn where the twist is imparted in two stages by means of a drawing frame co-operating with two centrifugal spindles and a spooling arrangement; said method comprising feeding fibre material to each centrifugal spindle from a separate delivery point, interrupting the feed after each centrifugal spindle is filled with partially twisted thread material to permit the material to be taken up by the spooling arrangement and given a final twist and controlling the working sequence so that at some stage material is supplied simultaneously to both centrifugal spindles.

2. A method according to claim 1, wherein the working sequence for each spindle comprises a spooling phase when material is taken up by the spooling arrangement and a delivery phase when material is taken up by the spindle and between the-spooling phase and the delivery phase there is a preparatory phase during the course of which the spindle can be cleaned and/or prepared for the next delivery phase.

3. A method substantially as described with reference to and as illustrated in the accompanying drawings.

Published 1990 at The Patent Office. State House. 66 71 High Holborn. London WCIR4TP-Fu.-.her copies maybe obtained from The Patent Office Sales Branch, St Mary Cray. Orpington, Kent BR5 3RD. Printed by MUItIPleX teci-Iniques ltd St Mary Cray. Kent, Con. V87