EP0368059B1 - Combing machine (lap piecing) - Google Patents

Description

The invention relates to a method and a device for attaching a new front lap end from a new lap to the outgoing lap end of a first lap in a combing machine.

It is known to arrange a detector device in such a combing machine, e.g. with a photocell or a light barrier, which switches off the machine when the end of the cotton tape runs off the roll. The carrying device is then loaded with a new wad of cotton by hand or by a transport device. The beginning of the cotton tape from the new roll is then placed manually on the (possibly torn to the correct length) end of the cotton tape from the previous roll and connected to it by pressing, after which the machine can start again.

From US-A-2 559 074 a generic device for automatic tracking of a cotton band of a new roll is known. The new reel is held in a reserve position above the first reel in progress and, when the first reel runs out, is moved down into the unwinding position. The new cotton end must be positioned in a forward-hanging position so that it comes to rest on the running cotton end during the lowering process. The outgoing cotton end is separated by a comb element in order to achieve a constant overlap with the new cotton end. The device described is complex and requires an exact positioning of the new cotton end in the reserve position, especially since the new cotton end is not prepared for the attachment process. Due to the unprepared new cotton end, different overlaps can occur with each new application process, which is particularly the case when changing at the same time (Block change) of several windings can adversely affect the quality of the comber belt to be formed.

The object of the invention is to propose a method or a device for a combing machine, wherein an automatic attachment of the beginning of a cotton tape from a new roll to the end of the cotton tape from the previous roll ensures a qualitatively constant and predetermined coverage of the two cotton wool ends becomes. This object is achieved by the proposed method according to claim 1.

This object for carrying out the method according to claim 1 is also achieved by the device according to the characterizing clause according to claim 2, it being proposed that a pair of transport rollers, means for the controlled cutting of a first cotton band from a first, move in the path of the cotton from the winding to the combing tools Wraps to form a first, rear lap end on the lap running to the combing tools and for controlled cutting of a second lap band from a new lap after the pair of transport rollers to form a second, front lap end, and a device for connecting the second lap end are arranged with the first cotton end, which device is a pair of press rollers arranged in the path of the cotton wool and a movable deflection element arranged thereon, by means of which the two cotton ends can be placed one on top of the other so that they can then be guided between the pair of press rollers.

For this purpose, a detector device can expediently be provided for ascertaining the point in time at which the first cotton band has almost completely run off the first lap. At this point in time, the detector device can start a control device, which then actuates the means mentioned for severing the first cotton band, then actuates a winding transport device for feeding a new lap to the carrying device, then actuates the means mentioned for severing the second cotton band and then actuates the device for Connect the second cotton end operated with the first cotton end.

The invention is also particularly suitable for a combing machine having one or more groups of combing heads, e.g. a group of eight comb heads or two groups of four comb heads each, the winding change in all comb heads of a group being carried out simultaneously by the control device described above carrying out the specified operations simultaneously on all comb heads of the group. To start the control device, each combing head of the group can then advantageously be assigned its own detector device, so that the control device is triggered as soon as the first cotton band has almost completely run off the first winding in a combing head of the group. Then the first cotton strips are automatically cut at the same height for all combing heads in the group, new windings are fed in, the second cotton strips are cut by the new windings at the same height and the cotton ends are connected to each other.

• Fig. 1 schematisch einen Kämmkopf einer erfindungsgemässen Kämmaschine und
• Fig. 2 bis Fig. 8 je einen Ausschnitt aus Fig. 1 bei anderen Stellungen und Betriebszuständen der Teile.

Embodiments of the invention are explained below with reference to the drawings. In these show:

• Fig. 1 shows schematically a combing head of a combing machine according to the invention and
• FIGS. 2 to 8 each show a section from FIG. 1 in other positions and operating states of the parts.

In Fig. 1, the essential parts of a combing head are shown in a schematic representation corresponding approximately to a vertical section. The essential combing tools of the combing head are a round comb 1, a fixed comb 2, two tear-off cylinders 3 and a pair of pliers with a pair of lower pliers 4 and a pair of upper pliers 5 which can be pivoted with respect to the lower pliers is fed. The cotton tape 7 comes from a roll 8, which is carried by a support device, which in the embodiment shown consists of two parallel winding rolls 9 and 10, on which the roll 8 rests.

A pair of transport rollers 9, 11, means for severing the cotton and a device for connecting a first cotton end 7b to a second cotton end 7b 'are arranged in the path of the cotton band 7 from the winding 8 to the combing tools 1-5, the first cotton end 7b being a is the rear end of the cotton tape running to the combing tools and the second cotton end 7b 'is a front end of a cotton tape 7' coming from a new roll, as will be explained in the following.

In the embodiment shown, said pair of transport rollers 9, 11 is formed by the front winding roller 9 and a pressure roller 11 cooperating with it. However, a pair of transport rollers separated from the front winding roller 9 could also be provided for the cotton coming from the winding 8. The pair of transport rollers 9, 11 is driven by a controlled drive device 12.

In the embodiment shown, the means for severing the cotton are set up to tear the cotton after the pair of transport rollers 9, 11. For this purpose, a second pair of transport rollers 13, 14 is arranged after the first pair of transport rollers 9, 11, which is controlled by a second controlled drive device 15 is driven. In normal operation of the combing machine, the two pairs of transport rollers 9, 11 and 13, 14 run at the same peripheral speeds. If a cotton belt 7 is to be cut or torn, the drive devices 12 and 15 are controlled as explained below so that they rotate the two pairs of transport rollers 9, 11 and 13, 14 at different peripheral speeds and / or in different directions, so that the Cotton tape breaks between the two pairs of transport rollers. It is possible, for example, to stop the first pair of transport rollers 9, 11 and to drive the second pair of transport rollers 13, 14 further or to drive the first pair of rollers 9, 11 in the opposite direction while the second pair of transport rollers 13, 14 is stationary. In both cases the cotton tape is cut.

The device for connecting a first cotton end to a second cotton end has a pair of press rollers 16, 17, which is driven by a drive device 18, and a movable deflection element for at least one of two cotton ends to be connected to one another. In the embodiment shown, the deflecting element is a slide 19 arranged in the direction of movement of the cotton band 7 in front of the pair of press rollers 16, 17, which is e.g. is moved by a cylinder-piston unit 20.

In Fig. 1 the combing head described is shown in normal operation. The cotton tape is unwound from the winding 8 by the rotation of the winding roller 9, and fed to the combing tools 1-5 by the pairs of transport rollers 13, 14 and 16, 17 rotating at the same circumferential speed and combed by them. The cotton tape 7, however, has almost completely run out of the winding 8 in FIG. 1. This point in time is now determined by a detector device, for example by a photocell 21, which runs through the end 7a of the cotton tape on the core 8a of the winding 8, by responding approximately to the different brightnesses and / or colors of the cotton tape 7 and the winding core 8a. Of course, other detector devices can also be used for the stated purpose.

The detector device 21 emits a signal to a control device 22, which thereupon the drive devices 12, 15 and 18 and other drive devices, described below, in the combing machine are controlled in such a way that a winding change is carried out automatically.

First, the control device 22 actuates a cylinder / piston unit 23 which swings the rear winding roller 10 downward, as shown in FIG. 2. The almost empty winding core 8a therefore rolls under the action of gravity on an inclined guide 24 to the rear except for a collecting device in the form of a trough-shaped plate 25. The remaining cotton band 7 is unwound from the core 8a.

The control device 22 then controls the drive device 12 (FIG. 1) in such a way that it stops the pair of transport rollers 9, 11 or rotates in the opposite direction. The cotton conveyor belt 7 is therefore torn between the two pairs of transport rollers 9, 11 and 13, 14 by the second pair of transport rollers 13, 14 which rotates normally, i.e. a new rear cotton end 7b at the point at which the combing tools 1 - 5 are connected is located at a precisely defined point running cotton tape 7 formed, as shown in Fig. 3.

The second pair of transport rollers 13, 14 and the pair of press rollers 16, 17 continue to rotate until the newly formed rear cotton end 7b is just in front of the pair of press rollers 16, 17, as shown in FIG. 4. Then the drive device 18 of the feed roller pair 16, 17 is switched off, and at the same time the combing tools 1-6 (FIG. 1) are stopped.

If the first pair of transport rollers 9, 11 has simply been stopped for tearing the cotton belt 7, the separated rear end section 7c of the cotton band 7 is now still held in this pair of transport rollers 9, 11, as shown in FIG. 4. The pair of transport rollers 9, 11 is therefore now rotated together with the second pair of transport rollers 13, 14 again in the forward direction in order to convey the end section 7c into a suction channel 26, through which it is removed. Instead, can the end section 7c can also be removed by means of a suction channel 27 arranged further back, in that the first pair of transport rollers 9, 11 is now rotated in the opposite direction until the beginning of the end section 7c falls into this suction channel 27. However, if the first pair of transport rollers 9, 11 has already been rotated sufficiently in the opposite direction to tear the cotton tape 7, then the beginning of the end section 7c can easily fall into the suction channel 27 and no further rotation is required.

Then, by actuating the cylinder-piston assembly 23, the rear winding roller 10 is pivoted back into its upper position or normal working position.

Thereafter, the control device 22 actuates a winding transport device, of which only one arm 28 with a support pin 29 is shown in FIG. 5. The winding transport device introduces a new cotton winder 8 'and places it on the winding rollers 9 and 10.

Then the transport roller pairs 9, 11 and 13, 14 are rotated in the forward direction. The winding roller 9 rotates the cotton roll 8 'resting on it. The jacket of the winding roller 9 is permeable to air, e.g. perforated, and in its interior a stationary tube 9a is arranged, which has a slot 9b in an upper region. A vacuum is now generated in this tube 9a, so that air is sucked in through the slot 9b and the air-permeable jacket of the winding roller 9. The beginning 7a 'of the cotton tape 7' from the new roll 8 'is therefore sucked in by the winding roller 9 as soon as it reaches it. As a result, the beginning 7 a ′ lies against the circumference of the winding roller 9, as shown in FIG. 5. The cotton belt 7 'is then moved downwards by the pairs of transport rollers 9, 11 and 13, 14.

After the beginning 7a 'of the cotton band 7' has passed through the second pair of transport rollers 13, 14, after a predetermined period of time has elapsed the first pair of transport rollers 9, 11 is stopped or the second pair of transport rollers 13, 14 is accelerated relative to the first pair 9, 11. As a result, the cotton tape 7 'between the two pairs of transport rollers 9, 11 and 13, 14 is torn, that is, a new front cotton end 7b' is formed at a precisely defined point on the cotton tape 7 'coming from the roll 8', as in Fig 6 shown.

The separated front end section 7c 'of the cotton band 7' is then sucked into the suction channel 26 and removed through it after it has passed completely through the second pair of transport rollers 13, 14.

The two pairs of transport rollers 9, 11 and 13, 14 then continue to run at the same peripheral speeds and move the cotton belt 7 'coming from the roll 8' downward. After the new front cotton end 7b 'has approximately reached the position shown in FIG. 7 in front of the press roller pair 16, 17 or between it and the slide 19, the control device 22 actuates the cylinder-piston unit 20 by the slide 19 to the left to move against the pair of press rollers 16, 17. The slider 19 comes into contact with the front cotton end 7b 'as shown in FIG. 8 and places the same on the rear cotton end 7b of the cotton tape 7, which is still held in the clamping area of the pair of press rollers 16, 17 and protrudes out of it, partially resting on the circumference of the lower press roll 17.

Then the drive unit 18 of the press roller pair 16, 17 and at the same time the drive devices of the combing tools 1-6 are switched on again. The rear cotton end 7b of the cotton band 7 is pulled onto the front cotton end 7b 'of the cotton band 7' lying thereon in the press roller pair 16, 17 which presses the two cotton ends 7b and 7b 'together and connects them to one another. The slide 19 is pulled back to the right by the cylinder-piston unit. The combing head resumes normal operation.

In FIG. 8 it is also shown that the collecting device 25 with the empty winding core 8a lying thereon has been raised to an upper position by a drive device in the form of a cylinder-piston unit 30. In this upper position, the empty winding core 8a is then gripped and removed by the winding transport device 28, 29 (FIG. 5), whereupon the collecting device 25 is lowered again into its starting position according to FIG. 1.

The described combing head can be arranged in a combing machine in a group of combing heads, in which common drive devices for the combing tools 1-5 of all combing heads of the group are provided. The control device 22 is then also jointly assigned to all of the terminal heads of the group. The drive devices controlled by the control device 22, in particular the drive devices 12, 15 and 18 and the cylinder-piston units 20, 23 and 30 as well as the means for generating negative pressure in the front winding roller 9 and in the suction channels 26 and 27 and the winding transport device (28, 29) can also be assigned to all combing heads of the group together (although in principle the common control device could also control separate drive devices etc.).

On the other hand, a separate detector device 21 (FIG. 1) is arranged for each comb head of the group. As soon as the cotton tape 7 from the winding 8 has almost completely run out in one of the combing heads, the detector device 21 in question emits a signal to the common control device 22, which then carries out the winding change described above for all comb heads of the group at the same time. At the beginning of the winding change, different lengths of the cotton tape 7 may still be present on the winding cores 8a in the various combing heads of the group; the new rear cotton ends 7b formed by the simultaneous cutting (tearing) of the cotton strips 7 between the pairs of transport rollers 9, 11 and 13, 14 then lie however, in all combing heads of the group at the same level. Likewise afterwards, the new front cotton ends 7b 'formed by tearing the new cotton strips 7' lie in all combing heads at the same height, even if the cotton wool beginning 7a 'is not exactly on the new cotton rolls 8' fed by the winding transport device (28, 29) same place of the circumference. Therefore, by means of the slider 19 (or a common slider 19) and the press rollers 16, 17, the front cotton ends 7b 'in all combing heads can be connected to the rear cotton ends 7b in the same way without any problems.

In the combing head described, both the cotton tape 7 from the roll 8 and afterwards the cotton tape 7 'from the new roll 8' are cut or torn by different driving of the two pairs of transport rollers 9, 11 and 13, 14 when changing the roll. In modified embodiments, however, separate means for cutting the cotton tape 7 and for cutting the cotton tape 7 'could of course also be arranged. Moreover, a second pair of transport rollers does not necessarily have to be used for the cutting, but instead other cutting devices that can be actuated by the control device 22 could also be used. be seen.

Claims (12)

1. A method of piecing a new leading lap end (7b') from a new lap roll (8') to the outgoing lap end (7b) of a first lap roll (8) in a combing machine, characterized by the following process steps:

   - Controlled severing of the outgoing lap ribbon (7) of the first lap roll (8) in order to form a first rear lap end (7b) in the lap ribbon travelling towards the combing tools;

   - positioned holding of the lap end (7b) of the outgoing lap ribbon (7) prepared by the severing process between a combing unit and a piecing means (19,20) which is arranged downstream of a carrying device (9,10) for the lap roll (8,8') in the running direction of the lap;

   - controlled severing of the supplied lap ribbon (7') of the new lap roll (8') in order to form a second leading lap end (7b');

   - controlled joining of the rear lap end (7b) of the outgoing lap ribbon (7) and the new leading lap end (7b') of the new lap ribbon (7') in the piecing means (19,20);

   - feeding the mutually joined lap ribbons (7,7') to the processing unit.
2. An apparatus for piecing a new leading lap end (7b') from a new lap roll (8') to the outgoing lap end (7b) of a first lap roll (8) in a combing machine for carrying out the method as claimed in claim 1 with at least one combing head which comprises combing tools (1-6) and a carrying device (9,10) for a lap roll (8;8') of a lap (7,7') to be combed, characterized in that in the path of the lap (7,7') from the lap roll (8;8') to the combing tools (1-6) there are arranged a pair of conveying rollers (9,11) , means (13,14,15) for the controlled severing of a first lap ribbon (7) from a first lap roll (8) in order to form a first rear lap end (7b) in the lap (7) travelling to the combing tools (1-6) and for the controlled severing of a second lap ribbon (7') from a new lap roll (8') after the pair of conveying rollers (9,11) in order to form a second leading lap end (7b') and a device (16,17,19) for joining the second lap end (7b') with the first lap end (7b), which device (16,17,19) comprises a pair of pressing rollers (16,17) arranged in the path of the lap (7;7') and a movable deflection element (19) arranged adjacent thereto, by means of which the two lap ends (7b, 7b') can be superimposed in order to be guided thereafter between the pair of pressing rollers (16,17).
3. An apparatus as claimed in claim 2, characterized by a detector device (21) such as a photocell for determining the time at which the first lap ribbon (7) has nearly completely wound off from the first lap roll (8) carried by the carrying device (9,10) and by the starting of a control device (22) which thereafter actuates the said means (13,14,15) for severing the first lap ribbon (7) and thereafter actuates a lap ribbon conveying apparatus (28, 29) for supplying a new lap roll (8') to the carrying device (9,10) and thereafter actuates the said means (13,14,15) for severing the first lap ribbon (7') and thereafter actuates the device (16,17,19) for joining the second lap end (7b') to the first lap end (7b).
4. An apparatus as claimed in claim 3, with at least one group of combing heads, characterized in that a separate detector device (21) is allocated to each combing head of the group and that the control device (22) can be initiated by each of the detector devices (21), which then carries out the said actuations in all combing heads of the group simultaneously.
5. An apparatus as claimed in one of the claims 2 to 4, characterized in that a device (26, 27) for removing the separated lap ribbon segments (7c; 7c') is arranged in the said means (13, 14, 15) for severing.
6. An apparatus as claimed in claim 5, characterized in that the device (26, 27) for removing the lap ribbon segments (7c; 7c') comprises at least one suction duct for the lap ribbon segments.
7. An apparatus as claimed in one of the claims 2 to 6, characterized in that the said means (13, 14, 15) for severing comprise a second pair of conveying rollers (13,14) between the first said pair of conveying rollers (9, 11) and the pair of pressing rollers (16, 17) and drive means (12, 15) which for driving the two pairs of conveying rollers (9, 11, 13, 14) can optionally be actuated either with practically the same circumferential speeds or with different circumferential speeds and/or in different directions of rotation.
8. An apparatus as claimed in claims 2 and 7, characterized in that the control device (22) is arranged in such a way that it actuates at first the drive means (12, 15) for differently driving the two pairs of conveying rollers (9, 11, 13, 14) in order to sever the first lap ribbon (7) between the two pairs of conveying rollers and to allow the first lap end (7b) to pass through the second pair of conveying rollers (13, 14) and it stops thereafter the pair of pressing rollers (16,17) and the combing tools (1-6) and actuates thereafter the drive means (12,15) for driving similarly the two pairs of conveying rollers (9, 11, 13, 14) until the initial part (7a') of the lap ribbon (7') of the new lap roll (8') has passed through both pairs of conveying rollers (9, 11, 13, 14) and thereafter actuates the drive means (12, 15) again for differently driving the two pairs of conveying rollers (9, 11, 13, 14) in order to sever the second lap ribbon (7') between the two pairs of conveying rollers and thereafter actuates the drive means (12, 15) again for driving similarly the two pairs of conveying rollers (9, 11, 13, 14) until the second lap end (7b') reaches the zone of the pair of pressing rollers (16, 17), whereupon the device (16, 17, 19) for joining the second lap end (7b') is actuated with the first lap end (7b).
9. An apparatus as claimed in one of the claims 2 to 8, wherein the carrying device (9, 10) is provided with a front and a rear lap roller for supporting the lap roll (8; 8'), characterized by a device (23) for lowering the rear lap roller (10) so that the lap roll (8) rolls backwardly into a catching device (25) while unrolling the lap (7).
10. An apparatus as claimed in one of the claims 2 to 9, wherein the carrying device (9, 10) is provided with a front and a rear lap roller for supporting the lap roll (8; 8'), characterized in that the front lap roller (9) is air-permeable and a pressure below atmospheric is produceable therein in order to detach the initial part (7a') of the second lap ribbon (7') from the circumference of the new lap roll (8').
11. An apparatus as claimed in one of the claims 2 to 10, wherein the carrying device (9, 10) is provided with a front and a rear lap roller for supporting the lap roll (8; 8'), characterized in that the first said pair of conveying rollers (9, 11) is formed by the front lap roller (9) and a pressing roller (11) cooperating with said lap roller.
12. An apparatus as claimed in one of the claims 2 to 11, characterized in that the deflection element (19) is movable towards the pair of pressing rollers (16, 17) in order to place the second lap end (7b') on the first lap end (7b) held in the pair of pressing rollers (16, 17).

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