WO2006003679A1

WO2006003679A1 - Apparatus and method for inserting and pre-feeding a sliver into a spinning unit

Info

Publication number: WO2006003679A1
Application number: PCT/IT2004/000367
Authority: WO
Inventors: Solitario Nesti; Marco Barbieri; Vittorio Colussi
Original assignee: Ministero Dell'istruzione, Dell'universita'e Della Ricerca
Priority date: 2004-06-30
Filing date: 2004-06-30
Publication date: 2006-01-12
Also published as: EP1769110B1; DE602004022597D1; EP1769110A1; ATE439462T1

Abstract

Equipement (10) for inserting and prefeeding a sliver (N) into a feed opining (A) of a spinning unit (F). The sliver is contained in a spinning can (V) located at the spinning unit (F) and has an end (4) outside the can (V). The equipment (10) comprises means (6, 7, 8) for seizing an end (4) of the sliver (N) and pulling a terminal portion (5) of the end (4), means (13, 14) for tapering the remaining terminal portion (11a) of the end (4) of the sliver (N), means (9, 18) for seizing and moving the end (4) of the sliver (N) to insert the tapered terminal portion (17) into the feed opining (A) of the spinning unit (F) and corresponding activating means (32, 33, 34) to activate the seizing and pulling means (6, 7, 8), the tapering means (13, 14) and the seizing and moving means (9, 18). Means (35, 37) are provided to control the prefeeding of the sliver (N) into the feed opening (A) of the spinning unit (F).

Description

"Apparatus and method for inserting and pre-feeding a sliver into a spinning unit"

DESCRIPTION

This invention relates to apparatus for inserting and prefeeding a sliver into a spinning unit according to the precharacterising clause of claim 1. In particular this invention finds application in the fieldi of spinning machines of the - open-end type in which the individual spinning units, which are in line at the front of the spinning machine, are provided with a mouth or opening for feeding the sliver.

Spinning machines produce bobbins of yarn from a fibrous structure having a high linear weight, commonly called sliver, which is held in containers or spinning cans on the ground close to and beneath the spinning units.

Various automated systems for moving cans between the machines used for filling them, storage areas and the spinning machines are known. These automated systems use overhead guides or guides on the ground and are capable of removing an empty can from beneath the spinning unit and replacing it with a full one from the storage area.

Once a full, can containing the sliver to be fed is ready close to the spinning unit the sliver has to be taken from the can and prepared and positioned for insertion into the feed opening of the spinning unit.

The sliver then has to be inserted and a brief

(prefeed) action of the device drafting the sliver within the spinning unit has to be put into effect. These operations were typically performed by the personnel operating the spinning equipment who had to carefully prepare the end of the sliver, checking its shape and consistency, for insertion into the feed opening, insert- the sliver prepared in this way and activate a prefeed. The duration of the prefeed is a critical parameter as regards the subsequent starting of spinning and must necessarily be entrusted to the judgement of the operator. In particular a correct quantity of prefed fibre is a determining factor for a correct start to spinning. Because the prefeed time is entrusted to the operator, an accumulation of fibre or, on the contrary, a shortage of fibre may occur, thus making it impossible to start spinning.

Given the importance and difficulty of these operations for^" the productivity of the spinning equipment and bearing in mind the need to reduce the personnel employed on the equipment, automated systems have been suggested for the insertion of sliver into the_ individual spinning units of open-end spinning machines. In this way the operator can manage a larger number of spinning units, thus increasing the productivity of the equipment and reducing the uncertainty and criticality of the manual operations performed in inserting the sliver in the feed opening to a minimum. An example of equipment for pneumatically seizing and feeding sliver into an open-end spinning machine is described in European patent application EP 770 717.

In accordance with the known art mentioned above the sliver is pneumatically picked up from the can through vacuum produced in a sliver feed device. Subsequently the sliver taken from the can is conveyed towards a series of guide devices to the card present in the spinning unit. However, equipment of the type mentioned above, although making it possible for the operation of feeding sliver to an open-end spinning unit to be performed automatically, has considerable disadvantages in terms of reliability and costs mainly because of the need to create a vacuum condition in order to feed the sliver, and the efficiency of the sliver feed operation.

As a consequence the need to have equipment for inserting and prefeeding sliver into a spinning unit which is more reliable, less costly and more efficient from the point of view of control and precise reproduction of the critical parameters in the operation is greatly felt.

The purpose of this invention is to provide equipment for inserting and prefeeding sliver into a spinning unit having structural and functional characteristics such as to satisfy the abovementioned requirements and at the same time to overcome the disadvantages mentioned with respect to the known art.

This object is achieved through equipment for inserting and prefeeding a sliver into a spinning unit according to a spinning unit according to claim 1. According to another aspect, an object of this invention is a method for inserting and prefeeding a sliver into a spinning unit according to claim 16.

Further features and advantages of the equipment and the method according to this invention will be apparent from the following description of a preferred embodiment provided by way of indication and non-restrictively with reference to the appended figures in which:

Figure 1 shows a diagrammatical view of equipment according to the invention for inserting and prefeeding a sliver into a spinning unit,

- Figure 2 shows a diagrammatical view of a spinning machine provided with a plurality of open- end spinning units capable of being used with the equipment of Figure 1, - Figure 3 shows a diagrammatical view of a moving supporting member for the equipment in Figure 1 and for the movement of cans,

- Figures 4 to 17 show diagrammatical views of details of the equipment in Figure 1 during different stages of operation.

With reference to the appended figures, 1 indicates as a whole a spinning machine comprising a plurality N of spinning units Fi of the open-end type, where i = 1 ... N. Each spinning unit Fi in spinning machine 1 is fed with corresponding sliver Ni contained in a spinning can Vi suitably positioned for the corresponding spinning unit Fi and beneath it.

In particular each spinning can Vi is positioned in a seat Si provided in the lower part of the corresponding spinning unit Fi (Figure 2) . Each spinning unit Fi has an opening A± for feeding the sliver Ni present in spinning can Vi.

For the purposes of explanation this description will refer in a non-restrictive way to one spinning unit F of spinning machine 1.

Advantageously spinning can V is transported to spinning unit F" by a moving unit or doffer 2 mounted on a guide member 3 to travel along the direction of the longitudinal extension of spinning machine 1, specifically the horizontal orientation X-X. Guide member 3 of mobile unit 2, located close to the working front of spinning unit Fi, may be of different types, as is known in the state of the art, and positioned in different ways, such as for example on the floor and/or overhead.

Mobile unit or doffer 2 may be provided, for example, with an on-board electrical switchboard, a station for the transport of full cans, a station for the transport of empty cans and for weighing them, and a device for picking up individual cans and placing them in their own seats.

In a manner which is in itself known can V carried by mobile unit 2 is discharged therefrom and positioned in the appropriate seat S provided in the lower part of spinning unit F. An end 4 of a sliver N located in spinning can V is positioned outside can V.

In the example illustrated in the appended figures, can V is of rectangular shape and end 4 of the sliver N projects (Figure 2) from the can from side 10 of can V located opposite spinning units F. In particular end 4 of sliver N is loose and extends along side 12 of can V in the vertical orientation Z- Z. It should be pointed out that end 4 of sliver N which lies outside the can typically has a minimum predefined length and is positioned close to the median part of side 12 of can V. Also can V comes from a can loading area in which a filling device known as a coiler, designed to control both the length and position of end 4 of sliver N lying outside each can Vi, is typically provided.

Subsequent^~to the positioning of can V in seat S of spinning unit F it is necessary to insert and prefeed a suitable quantity of sliver N contained in can V into the feed opening A of spinning unit F.

With reference to the appended figures, 10 indicates as a whole equipment according to this invention for inserting and prefeeding a sliver N into spinning unit F. In particular sliver N must be inserted into the feed opening A of spinning unit F. Advantageously, equipment 10 is mounted on mobile unit 2 used for moving and/or loading/unloading cans at the various spinning units Fi (Figure 3) . Alternatively equipment 10 may be mounted on a separate mobile unit which can move on the same guide member 3 or on another different guide member, or is housed on a service unit 21 for cleaning and starting spinning within the open-end unit. Equipment 10 comprises means for seizing a sliver N and pulling a portion of sliver N so as to determine an optimum length for insertion.

In particular the seizing and pulling means are capable of seizing end 4 of the sliver N extending from can V and pulling a terminal portion 5 of that end 4. _

Advantageously the seizing and pulling means comprise three seizing members 6, 7, 8 comprising two corresponding opposing seizing members 6a, 7a, 8a and 6b, 7b, 8b working together in the manner of a jaw to seize different portions of end 4 projecting from can V.

In particular seizing members 6a, 7a, 8a and 6b, 7b, 8b can move reciprocally towards the median part of the side 12 of can V in the X-X orientation. In this way seizing members 6, 7, 8 can effectively seize the end of the sliver when this is positioned in a different way with respect to the median part of the can, which acts as a known reference point.

Seizing members 6, 7 are in a fixed position with respect to each other along the vertical Z-Z orientation, but seizing member 8 can move away from and towards seizing members 6, 7 along this vertical Z-Z orientation. Moving member 8 moves in a movement away from seizing members 6, 7 along the Z-Z orientation in the direction indicated by Z- in the appended figures. In this movement away from seizing members 6, 7 moving seizing member 8 acts on end 4 of roving N to pull terminal portion 5 of end 4. The approaching movement towards seizing members 6, 7, indicated by Z+, is instead necessary in order to re¬ establish the original position of seizing members 6, 7, 8 in order to perform another pulling operation on a new end of the sliver.

As shown in Figures 4 and 5, the group of seizing members 6, 7, 8 can move in the Y-Y orientation to advance towards the side 12 of can V from which end 4 of sliver N projects. In this specific instance the Y-Y orientation corresponds to the direction of the depth of spinning unit F and Y+ indicates the direction of advance of the group of seizing members 6, 7, 8 towards spinning unit F. The advance of the group of seizing members 6, 7, 8 along the Y-Y orientation in the Y+ direction must be stopped at a position such as to enable seizing members 6, 7, 8 to seize end 4 of sliver N correctly. For _this purpose it is possible to provide a detector or a system of position sensors which determines the presence and precise position of can V.

In Figure 4, Li indicates the distance measured along the Z-Z orientation between seizing members 6 and 7, while L₂ indicates the distance measured along the Z-Z orientation between seizing members 7 and 8 in the resting position.

Because distance Li is fixed, length 11 of end 4 of sliver N lying between seizing members 6 and 7 can be unequivocally- identified in respect of length and above all position. This arises specifically from the fact that the two seizing members 6, 7 remain fixed with respect to each other during the movement performed by moving seizing member 8 along the vertical Z-Z orientation in the Z- direction in order to pull terminal portion 5 of end 4 of sliver N.

The distance L₂ from moving seizing member 8 to seizing members 6, 7 can be adjusted according to the type of fibre, in particular according to the specific length of the fibres which form the sliver N.

In this respect it should be pointed out that the pull effected by moving jaw 8 causes fraying of the fibres of _sliver N with the consequence that terminal portion 11a of length 11 of end 4 of sliver N remaining below seizing member 7 after the pull effected by moving seizing member 8 takes the form of a "tuft" of fibres predominantly aligned with respect to the axis of terminal portion 11a. In order to be able to insert portion 11a into feed opening A and therefore prefeed sliver N into spinning unit F it is necessary to taper terminal portion 11a of length 11 of sliver N. With this object equipment 10 comprises means for tapering the remaining terminal portion 11a of end 4 of the sliver N.

Advantageously the tapering means comprise two members 13, 14 having corresponding surfaces 13a, 14a which can face each other. Terminal portion 11a of sliver N is capable of being positioned between the two surfaces 13a, 14a and extends in a direction corresponding to the actual direction of the extension of the terminal portion 11a of sliver N. In the example illustrated in Figures 10-11, terminal portion 11a positioned between the two surfaces 13a, 14a extends in the vertical Z-Z orientation.

The two members 13, 14 are mobile to carry the two surfaces 13a, 14a against each other in such a way that at least a portion of the corresponding surfaces 13a, 14a engages with the terminal portion 11a of sliver N. In the example the two members can move in the horizontal X-X orientation.

In order to taper the terminal portion 11a of sliver N, at least one of the two surfaces 13a 14a can move so as to move with respect to the other in a direction, in the case in point along the Y-Y orientation, substantially perpendicular to the Z-Z orientation of the extension of terminal portion 11a between the two surfaces 13a, 14a, that is in the Z-Z orientation with respect to which tapering of terminal portion 11a occurs.

Advantageously both surfaces 13a, 14a can move in the opposite direction to the other along the Y-Y orientation. This relative movement between the two surfaces 13a, IJa of members 13, 14 makes it possible to impress an axial rotation upon the fibres of terminal portion 11a which brings about tapering of terminal portion 11a. Advantageously surfaces 13a, 14a and terminal portion 11a can also move with respect to each other along the Z-Z orientation of tapering terminal portion 11a requiring tapering.

This makes it possible to optimise the operation of tapering terminal portion 11a. As will be more apparent from the description below, this optimisation operation brings many advantages from the point of view of inserting and prefeeding sliver N, in that it makes it possible to obtain a constant spatial positioning and a constant consistency of point lib with_. respect to the Z-Z orientation of tapering terminal portion 11a requiring tapering over the course of several working cycles.

According to a preferred embodiment, members 13, 14 take the form of two annular bands supported by corresponding groups of rotating rollers 15, 16. In order to bring about relative movement of surfaces 13a, 14a of bands 13, 14, rollers 15 and 16 of members 13 and 14 are arranged so as to rotate about their corresponding axes of rotation parallel to the Z-Z orientation of tapering terminal portion 11a requiring tapering.

In the remainder of the description and with reference to Figures 11 to 17, 17 indicates the tapered portion of the terminal portion 11a of end 4 of sliver N obtained using the tapering means described above. Tapered portion 17 is intended to be inserted into the feed opening A of spinning unit F. In particular tapered portion 17 is inserted into feed opening A in a direction of insertion which is parallel to the Y-Y orientation in the direction indicated by Y+ in the figures.

Typically feed means for sliver N (not illustrated in the appended figures) are present in feed opening A of spinning unit F.

According to a preferred embodiment, the feed means comprise-devices for drafting sliver N which are capable of delivering the same to the spinning devices (these also not illustrated in the appended figures) . Furthermore this drafting function is performed by one or more feed rollers located in such a way as to convey the sliver and deliver it appropriately.

For example, the feed rollers may comprise a knurled rotating cylinder capable of acting together with a wall which can move towards and away from the cylinder. In particular the wall can move towards the knurled cylinder to press tapered portion 17 of sliver N inserted into feed opening A against the knurled members of the rotating cylinder. Operation of the feed means, that is the knurled cylinder, for a predetermined length of time ΔT thus brings about the prefeeding of sliver N. With reference to what has been mentioned above, the advantage provided by this invention in which the prefeed operation is extremely precise and rapid because of the- -constancy of tapered portion 17 of sliver N and the duration ΔT of the prefeed operation, which causes a suitable quantity of fibre to be inserted into the drafting devices, is obvious. In particular, equipment 10 according to the invention has made it possible to achieve results with the insertion of sliver N which are constant during several working cycles. It is therefore important to be able to have a tapered portion 17 with a tip 17b which is in a constant position with respect to the members seizing and moving the end of the sliver N so^" that the process parameter settings remain constant for different slivers fed to the various spinning units.

In particular, from tests performed it has been noted that further fine optimisation of the insertion and prefeeding of sliver N is achieved with a tapered portion 17 which is free from hooks and not excessively twisted. With this object it is possible to use control software programs for all the devices involved in the operation of tapering terminal portion 11a, such as the seizing and moving means and the tapering means proper. Equipment 10 also comprises means for seizing and moving end 4 of sliver N and for inserting tapered terminal portion 17 into feed opening A.

Advantageously the means for seizing and moving end 4 of sliver N comprise a- seizing and moving member 9 (Figures 1 and 4 to 13) capable of transporting the seized length 11 of end 4 of sliver N remaining after the pull performed by moving seizing member- 8 and inserting tapered terminal portion 17 into the feed opening A of spinning unit F.

In accordance with a preferred embodiment seizing member 9 takes the form of a clamp 9 defined by two jaws 9a, 9b which are hinged together and can close to seize length 11 of end 4 of the sliver and which are mounted on a base rotating about the axis of seizing member 9, in Figures 8 and 9 about an axis parallel to the X-X orientation.

Preferably, the closure of clamp 9 on length 11 of end 4 lying^"between members 6 and 7 is controlled at the same time as the movement of moving seizing member 8 (Figure 7) . As an alternative the closure of clamp 9 may also be controlled immediately before or after moving seizing member 8 has pulled terminal portion 5 of end 4 of sliver N. The operation of inserting tapered portion 17 into opening A can be performed by seizing and moving member 9 which following the tapering operation can continue to grip length 11 of end 4 of sliver N and be controlled in such a way as to insert tapered portion 17 into feed opening A.

However, with reference to the specific embodiment illustrated in the appended figures, it will be noted ^" that spinning machine F has a longitudinal guide 19 (Figure 2) on which there moves moving member 20 which is capable of transporting a service unit 21 along the different spinning units Fi. In the embodiment illustrated in the appended figures longitudinal guide 19 is located along vertical Z-Z orientation beneath the level at which feed opening A is located. Typically service unit 21 is designed for the transport of automatic systems for cleaning and starting spinning within inactive spinning units Fi or other auxiliary systems . Longitudinal guide 19 supporting moving member 20 which transports service unit 21 represents a hazard for sliver N in that said sliver N will pass above guide 19. In this case sliver N would in fact interfere with moving unit 20 which moves on guide 19. In order to overcome this disadvantage the means for inserting tapered portion 17 into feed opening A comprise a second seizing and moving member 18 (Figures 13 to 17) capable of taking tapered terminal portion 17 from said first seizing and moving member 9 in order to insert it into the feed opening A of spinning unit F.

In accordance with a preferred embodiment seizing and moving member 18 takes the form of a clamp 18 formed by two jaws 18a, 18b which act together to grasp terminal portion 17 of end 4 of sliver N. It must be pointed out that the need to provide a second seizing and moving member 18 which is separate from seizing and moving member 9 may arise from other requirements of a structural and/or functional type for equipment 10 and spinning machine 1.

With reference to the embodiment illustrated in the appended figures and as described above, the insertion of tapered portion 17 between the moving wall and the rotating knurled cylinder requires the moving wall to move towards and away from the knurled cylinder, which is not illustrated because it is conventional. This operation may be critical for the purpose of synchronising movement of the moving wall and the movement of inserting tapered portion 17 between the cylinder and the wall. In order to avoid this operation, equipment 10 according to the invention advantageously comprises means to assist the insertion of tapered terminal portion 17 of sliver N into the feed opening A of spinning unit F.

In accordance with the preferred embodiment the means for assisting the insertion of tapered portion 17 comprise a _ shaped member 22 capable of acting directly on tapered portion 17 to permit the feed means, that is the moving wall and the knurled feed cylinder, to grasp tapered portion 17. In particular shaped member 22 is of a "blade" shape so as to be able to be inserted into feed opening A at the same time as tapered portion 17 of sliver N borne by the seizing and moving means.

In order to make it possible for the feed means to engage tapered portion 17, shaped member 22 can move towards and away from feed opening A in a direction which"coincides with the Y-Y orientation in which tapered portion 17 is inserted into opening A. In this way the need to control movement of the moving wall away from the knurled cylinder to grip tapered portion 17 is avoided in that this operation is performed by shaped member 22. Also the quantity of fibre affected by gripping is controlled and repeatable. It will be noted that whether member 9 is used directly, or whether second seizing and moving member

18 is necessary in order to carry tapered portion 17 to feed opening A, it is necessary to perform a movement in the vertical Z-Z orientation.

This movement in the vertical Z-Z orientation requires that a quantity of sliver N, typically laid in a circular loop within can V, be taken from can V, and these loops may cause end portion 23 of end 4 of sliver N, which is above member 18, to snake in the X-X orientation and cause it to interfere with the adjacent devices. This could cause end portion 23 of end 4 to breaky - thus bringing the operation already performed on sliver N to naught. If this occurs insertion and prefeed has to be performed manually by the operator.

In order to overcome this disadvantage, equipment 10 according to the invention comprises means for guiding sliver N which are capable of guiding end portion 23 of end 4 of sliver N located above the seizing and moving means and below can V.

The purpose of these guide means is to prevent end portion 23 of sliver N from interfering with the other devices of equipment 10 during the stage of inserting tapered portion 17 into feed opening A performed by the seizing and moving member of equipment 10 according to the invention.

In the example illustrated in the appended figures, the guide means comprise a pair of forks 24a, 24b which can control end portion 23 of end 4 of sliver N and guide it.

Spinning unit F also comprises a sliver guide ring 25 positioned on the front part of spinning unit F in order to ensure that sliver N is correctly positioned during spinning. For the purposes of using equipment 10, sliver guide ring 25 is conveniently hinged to rotate about a pin 26 which extends in the vertical Z-Z orientation. In particular sliver guide ring 25 can move between a closed position in which with a U-shaped sliver passage member 27 it forms a through opening 28 extending in the Z-Z orientation capable of permitting sliver N to pass and an open position in which sliver N is pressed against sliver passage member 27. In order to open sliver guide ring 25 equipment 10 according to the invention comprises a pusher 29 (Figures 1 and 13 to 17) capable of acting in the Y+ direction on a fixed stop member 30 provided on sliver guide ring 25.

Advantageously, when opening, ring 25 rotates against resilient means (not illustrated in the figures) which are designed to hold sliver guide ring 25 in the closed position and oppose its opening brought about by pusher 29 and at the same time to assist its closure when pusher 29 is released.

Equipment 10 also comprises corresponding activating means for activating the seizing and pulling means, the tapering means and the seizing and moving means.

The activating means may, for example, comprise pneumatic activators, electric motors including stepping motors or other conventional means normally used to automate the movement of two or more parts. Furthermore equipment 10 may be provided with command and control means to control the operation of the aforesaid activating means. As illustrated in the figures, equipment 10 comprises motor means 32 to move seizing member 8 in relation to seizing members 6, 7 in the vertical Z-Z orientation and_ to move seizing members 6a, 7a, 8a and 6b, 7b, 8b, motor means 33 to effect opening and closing of jaws 9a, 9b of seizing and moving member 9 and to move and rotate the same, motor means 34 to move tapering members 13 , 14 and to cause rollers 15, 16 to rotate.

The equipment also comprises corresponding motor means (not illustrated in the figures) to move forks 24a, 24b, pusher 29, shaped member 22, seizing and moving member 18 and to cause the jaws 18a, 18b of member 18 itself to open and close.

Control means are also provided to control the means for feeding sliver N for the predetermined time interval ΔT and to achieve the prefeed of sliver N.

According to a preferred embodiment the means controlling the prefeed comprise a pusher member 35 which can press on an operating switch 37 located in the front part of spinning unit F and capable of controlling activation of the means feeding sliver N present in feed opening A for a predetermined period of time ΔT. _

Alternatively the prefeed control means comprise a system of sensors capable of establishing that the tapered portion 17 of sliver N has been engaged with the feed means for sliver N present in feed opening A so as to control operation of the feed means themselves for a predetermined period of time.

Advantageously seizing and moving member 18, forks 24a, 24b, pusher 29, shaped member 22 and pusher member 35 are supported so that they can move on a "poll"-shaped member 36 (Figure 1) to permit the aforesaid devices to advance in the Y+ direction.

Advantageously the equipment comprises means (not illustrated in the figures) to establish optically or by contact that the various portions of the sliver are__present and in the correct position throughout the cycle, and control means whose function is to stop the cycle and provide a warning in the event of malfunction. The method of inserting and prefeeding sliver into a spinning unit of the open-end type will now be described.

It is assumed that end 4 of the sliver N is positioned close to halfway along side 12 of can V and extends beyond a certain minimum length in the Z- Z orientation.

During a first stage of the method the means for seizing sliver N and pulling terminal portion 5 of sliver N are activated. First of all seizing members 6, 7, 8 are caused to advance along the Y-Y orientation in the Y+ direction (Figures 4 and 5) towards side 12 of can V until specific sensors or a detector element, not illustrated because it is conventional, detects the presence and precise position of can V. At this point the corresponding opposing seizing members 6a, 7a, 8a and 6b, 7b, 8b are activated to move towards each other towards the median part of side 12 of can V along the X-X orientation. When seizing members 6, 7, 8 seize end 4 of sliver N (Figure 6) moving seizing member 8 is activated to move along the Z-Z orientation in the Z- direction (Figure 7) away from seizing members 6, 7 so as to pull terminal portion 5 of end 4.

When seizing member 8 has pulled the sliver, seizing members 8a, 8b open to release terminal portion 5, which is collected, for example, in a container beneath.

At the same time (Figure 8) , jaws 9a, 9b of clamp 9 are offered up to length 11 of the sliver and caused to close to seize length 11 of end 4 of sliver

N remaining after it has been pulled by moving seizing member 8.

Subsequently clamp 9 completes a rotation through 180° (Figure 9) , appropriately about the X-X orientation, in such a way as to bring the extremity of tip lib of length 11 of end 4 in the Z+ direction. At this point the two annular bands 13, 14 are caused to advance in the Y+ direction (Figure 10) so that terminal portion 11a of sliver N is positioned between the two surfaces 13a, 14a in the Z-Z tapering orientation corresponding to the axial orientation of terminal portion 11a of sliver N. Alternatively clamp

9 may move in the Y- direction to position terminal portion 11a of sliver N between the two surfaces 13a, 14a. Then the two annular bands 13, 14 move towards each other along the X-X orientation or rotate about axes parallel to Z-Z in order to bring the two surfaces 13a, 14a together. In this way the two surfaces 13a, 14a engage terminal portion 11a of sliver N. At this point rollers 15 and 16 are caused to rotate about their corresponding axes of rotation in order to taper terminal portion 11a of sliver N.

In order to optimise the operation of tapering terminal portion 11a the two members 13, 14 and clamp 9 may be caused to move reciprocally in the Z-Z tapering orientation for terminal portion 11a which is to be tapered (Figure 11) .

After completing the operation of tapering terminal portion 11a clamp 9 is advantageously caused to rotate through 90° about the X-X orientation

(Figure 12) in such a way as to move the tip 17b of tapered portion 17 away from the orientation in the

Z+ direction to that in the Y+ direction which is necessary for tapered portion 17 to be inserted into feed opening A of spinning unit F. Clamp 9 is then moved for a predetermined distance along the Y-Y orientation in the Y+ direction towards spinning unit F (Figure 13) . In this way tapered portion 17 is ready to be seized by clamp 18 which for the purpose moves in the Y+ direction together with member 36 and at the same time in the Z- direction in order to lie adjacent to clamp 9 to seize end 4.

In this way clamp 18 can close (Figure 14) to seize end 4 which is thus constrained to pass from the lower part of guide 19. After clamp 9 opens

(Figure 15) clamp 18 moves along the Z-Z orientation in the Z+ direction to bring the tip 17b of tapered portion 17 to the level of feed opening A (Figure

16) . At the same time pair of forks 24, 25 is caused to advance in the Y+ direction, and also if appropriate in^""the Z- direction, to guide the tail portion 23 of end 4 of sliver N while this is lifted from the can (Figure 17) .

Clamp 18 now moves in the Y-Y orientation to insert tapered portion 17 in feed opening A. At the same time as this movement occurs pusher 29 acts in the Y+ direction on fixed stop member 30 to cause ring 25 to rotate about pin 26 against the force (Figure 17) . When clamp 18 has inserted part of tapered portion 17 into feed opening A, pusher 29 is released in the Y- direction onto fixed stop member 30 and ring 25 closes under the force of the resilient means. As stated, in spinning unit F there is a sliver drafting device, typically comprising a knurled rotating cylinder acting together with a wall which moves towards and away from the cylinder.

Shaped member 22 is used to assist prefeeding sliver N, which must be preceded by tightening tapered portion, -17 of sliver N between the cylinder and the moving wall. In particular shaped member 22, which is of a "blade" shape, is inserted into feed opening A at the same time as tapered portion 17 of sliver N borne by clamp 18. In particular shaped member 22 moves away from and towards feed opening A along the Y-Y orientation in the Y+ direction in which tapered portion 17 is inserted into opening A.

As an alternative the outer portion of feed opening A may be provided with a member (not illustrated in the figures), called a "tablet", the pressure of which, provided by appropriate control means, controls movement of the moving wall away from the knurled cylinder. In this way the tapered portion can be inserted between the moving wall and the knurled cylinder without the intervention of the shaped member described above. Subsequently release of the "tablet" allows tapered portion 17 to be engaged with the feed means.

According to another alternative the two aspects described above can be combined and provision may be made for use of the shaped member in addition to the "tablet" .

After tapered portion 17 has been inserted into feed opening A, and it has been seized by the feed cylinder, prefeeding is carried out by operating the drafting devices for sliver N present in spinning unit F for a short time, this being effected through the pressure of pusher member 35 on operating switch 37 which controls activation of the means feeding sliver N present within feed opening A. Switch 37 is activated for a predetermined period of time ΔT sufficient to allow sliver N to be seized by the drafting devices present in feed opening A. It should in fact be pointed out that prefeeding the correct quantity of fibre is essential for the correct starting of spinning. Period of time ΔT must therefore be such as not to give rise to either an accumulation of fibre or on the other hand an insufficiency of fibre. For example, time period ΔT may be between a few tenths of a second and up to a few seconds. ^~~

A mechanical device or an air jet, not illustrated in the figure, must then act to release portion 23 of sliver end 4 from jaw 9b of member 9 (Figure 17) and permit it and member 36 to move along the Y-Y orientation in the Y- direction in order to set up equipment 10 for further action.

At this point spinning unit F is ready and sliver N can be correctly fed to the spinning devices in spinning unit F.

As may be appreciated from what has been described, the equipment according to this invention makes it possible to satisfy the requirements and overcome the disadvantages mentioned in the introductory part of this description with reference to the known art.

The advantages deriving from the use of this invention lie mainly in the fact that it provides equipment capable of simplifying, speeding up and automating all_ the operations of inserting and prefeeding a sliver into a spinning unit following the arrival of a can containing a sliver to be fed, rendering it more reliable.

In particular the equipment may operate in combination with a moving unit for the transport of bins along the various spinning units of the spinning machine. After an empty can has been replaced by a full can the equipment seeks the end of the sliver and prepares its end performing a pulling and tapering operation which ensures that the tip has the appropriate length, shape and consistency. The tip treated in this way is then inserted into the devices feeding sliver to the card present in the spinning unit, and controls appropriate prefeeding. The equipment can be installed in combination with moving can transport unit 2, as illustrated in Figure 1, or on means which interact with the spinning units, for example appropriately service unit 21.

Obviously in order to satisfy contingent and specific requirements the person skilled in the art may apply many modifications and variants to the equipment and method according to the invention described above, all of which are nevertheless included within the scope of protection of the invention as defined by the following claims.

Claims

1. Equipment (10) for inserting and prefeeding sliver (N) into a feed opening (A) of a spinning unit

(F) , the said sliver (N) being contained in a spinning can (V) positioned at the said spinning unit

(F) and having an end (4) outside the said can (V) , means for feeding the said sliver (N) being provided in the said feed opening (A) of the spinning unit

(F) , the said ^"equipment (10) being characterised in that it comprises:

- means (6, 7, 8) for seizing the said end (4) of the sliver (N) and pulling a terminal portion (5) of the end (4) ,

- means (13, 14) for tapering the remaining terminal portion (lla) of the end (4) of the sliver

(N),

- means (9, 18) for seizing and moving the end (4) of the sliver (N) in order to insert the tapered terminal portion (17) into the feed opening (A) of the said spinning unit (F) ,

- corresponding activating means (32, 33, 34) being provided to activate the seizing and pulling means (6, 7, 8), the tapering means (13, 14) and the seizing and moving means (9, 18) , and - controls .means (35, 37) being provided to control the said means feeding the sliver (N) into the feed opening (A) for a predetermined period of time (ΔT) so as to prefeed the said sliver (N) into the said feed opening (A) .

2. Equipment (10) for inserting and prefeeding a sliver (N) according to claim 1, in which the said seizing and pulling means comprise three seizing members (6, 7, 8) capable of seizing different portions of the end (4) of the sliver (N) , one seizing member (8) of the said seizing members (6, 7, 8) being capable of movement with respect to the other two seizing members (6, 7) in a predetermined orientation (Z-Z) to pull the said terminal portion (5) of the end (4) of the sliver (N) .

3. Equipment (10) for inserting and prefeeding sliver (N) according to claim 2, in which the said three seizing members (6, 7, 8) comprise two corresponding opposing seizing members (6a, 7a, 8a, 6b, 7b, 8b) acting together in the form of jaws to seize the said different portions of the end (4) of the sliver (N) .

4. Equipment (10) for inserting and prefeeding a sliver (N) according to any of claims from 1 to 3, in which the said seizing and pulling means can move to seize the end (4) of the sliver (N) projecting from the can (V) .

5. Equipment (10) for inserting and prefeeding a sliver (N) according to any of claims 1 to 4, in which the said means for tapering the remaining terminal portion (lla) of the end (4) of the sliver (N) comprise two members (13, 14) having corresponding surfaces (13a, 14a) through which the said remaining terminal portion (Ha) which is to be tapered can _ be positioned extending in a predetermined tapering orientation (Z-Z) , the said two members (13, 14) being capable of movement to carry the surfaces (13a, 14a) which face each other and engage the terminal portion (Ha) which has to be tapered, at least one of the two surfaces being capable of moving to move with respect to the other in an orientation (Y-Y) which is substantially perpendicular to the said tapering orientation (Z-Z) .

6. Equipment (10) for inserting and prefeeding a sliver (N) according to any of claims 1 to 5, in which the said-means for seizing and moving the end (4) of the sliver (N) comprise a first seizing and moving member (9) capable of seizing the length (11) of the end (4) of the sliver (N) remaining after pulling and a second seizing and moving member (18) capable of taking the tapered terminal portion (17) from the said first seizing and moving member (9) in order to insert it into the feed opening (A) of the said spinning unit (F) .

7. Equipment (10) for inserting and prefeeding a sliver (N) according to claim 6, in which the said seizing and moving means can move to present the said remaining terminal portion (lla) which has to be tapered between the two surfaces (13a, 14a) in the said predetermined tapering orientation (Z-Z) .

8. Equipment (10) for inserting and prefeeding a sliver (N) according to any one of claims 1 to 7, in which the said control means (35, 37) comprise a pusher member (35) capable of pressing on an activating puslT^"switch (37) provided on the spinning unit (F) and capable of controlling activation of the said means for feeding the sliver (N) .

9. Equipment (10) for inserting and prefeeding a sliver (N) according to any of claims 1 to 8, in which the said means for feeding the sliver (N) comprise a knurled rotating cylinder capable of acting together with a wall which can move towards and away from the cylinder in order to press the tapered portion (17) of the sliver (N) against the knurled members of the rotating cylinder.

10. Equipment (10) for inserting and prefeeding a sliver (N) according to any of claims 1 to 9, comprising means for assisting insertion of the tapered portion (17) into the feed opening (A) , the said assistance means comprising a blade-shaped member (22) capable of acting directly on the said tapered portion (17) to permit the said feeding means for the sliver (N) to engage the tapered portion

(17) .

11. Equipment (10) for inserting and prefeeding a sliver (N) according to any of claims 1 to 10, comprising means for guiding the sliver which are capable of guiding the end portion (23) of the sliver (N) lying between the seizing and moving means (9, 18) and the can (V) .

12. Equipment (10) for inserting and prefeeding a sliver (N) according to claim 11, in which the said means for guiding the sliver comprise a pair of forks (24a, 24b) capable of guiding the said end portion (23) of the end- (4) of the sliver (N) .

13. Equipment (10) for inserting and prefeeding sliver (N) according to claim 12, in which the said means for guiding the sliver comprise a sliver guide ring (25) which can move between a closed position in which together with a sliver passage member (27) it forms a through opening (28) for passage of the sliver (N) and an open position in which the sliver (N) is brought alongside the sliver passage member (27) .

14. Equipment (10) for inserting and prefeeding a sliver (N) according to claim 1, in which the said means for seizing and moving the end (4) of the sliver (N) comprise a seizing and moving member capable of seizing the remaining portion (11) of the end (4) of the sliver (N) and inserting the tapered terminal portion (17) into the feed opening (A) of the said spinning unit (F) .

15. Equipment (10) for inserting and prefeeding a sliver (N) according to any of claims 1 to 14, in which the said spinning unit (F) comprises a sliver guide ring (25)_ which can be moved between a closed position in which together with a U-shaped sliver passage member (27) it forms a through opening (28) capable of permitting the passage of the sliver (N) and an open position in which the sliver (N) is brought alongside the sliver passage member (27) .

16. Method for inserting and prefeeding a sliver (N) into a feed opening (A) of a spinning unit (F) , the said sliver (N) being contained in a spinning can

(V) positioned at the said spinning unit (V) located at the said spinning unit (F) and having an end (4) outside the said can (V) , means for feeding the said sliver (N) being provided in the said feed opening (A) of the spinning unit (F) , the said method (10) comprising the stages of: - seizing the said end (4) of the sliver (N) ,

- pulling a terminal portion (5) of the end (4) ,

- tapering the remaining terminal portion (lla) of the end (4) of the sliver (N) , - inserting the terminal tapered portion (17) into the said feed opening (A) of the said spinning unit (F) , and

- controlling the prefeeding of a portion of the sliver (N) into the feed opening (A) for a predetermined period of time (ΔT) .