EP2141271B1 - Flat knitting machine with knitted fabric take-down device - Google Patents

Description

The invention relates to a flat knitting machine with knitted fabric removal apparatus having a plurality of front, arranged below the front needle bed extraction organs and a plurality of rear, arranged below the rear needle bed exhaust organs, the front and rear take-off organs are arranged on both sides of the trigger gap for the fabric in pairs opposite each other and the fabric between the front and rear trigger members frictionally clamped and peeled off by this.

For the production of knitted fabrics which have a sophisticated patterning technique and shape, it is advantageous if an optimal peel force is exerted on the knitted piece for each stitch course to be formed.

There were therefore developed in the past extraction devices in which the knit as close as possible below the knitting needles carrying needle beds arranged detected and withdrawn.

That's how it describes DE 28 03 135 C2 a trigger device with cam flaps, which have a wavy front side and engage with this in the fabric to pull it off. On the opposite side of the knitted fabric, a smooth contact surface is provided for the knitted fabric. This known device has the disadvantage that in a dull wavy end face of the entrainment flaps a safe knitted fabric is not guaranteed, while a serrated profiling of the front sides carries the risk that capillary filaments of the fabric are injured, whereby the knit surface is roughened.

From the EP 0 841422 B1 a withdrawal device is known in which engage with Nähnadelspitzen deduction organs in the fabric and deduct this. The deduction organs are arranged in pairs on the front and rear side of the knitted fabric and stored in guide beds. Again, there is a risk that the Nähnadelspitzen roughen the knit surface.

The EP 0 523 662 B1 describes a trigger device with opposing grippers, which clamp the fabric frictionally between them and peel off. The arranged under the rear needle bed gripper are attached to an angle bar and perform by this their pivotal movements together. On the front side of the knitted fabric, the grippers are individually pivotable. However, the movement of the gripper pivoted away from the fabric into its starting take-off position is common on both sides of the fabric over the entire length of the needle bed, so that the grippers are unable to exert a spreading action on the fabric. If a spreading action is to be exerted on the fabric, an additional clamping device for the fabric must be provided in this solution for the extraction device.

The present invention has for its object to provide a knit removal device of a flat knitting machine, which deducts the fabric safely and gently with the required for the stitch to be formed withdrawal force.

The object is achieved by a flat knitting machine with a fabric draw-off device with a plurality of front, arranged below the front needle bed exhaust organs and a plurality of rear, arranged below the rear needle bed exhaust organs, the front and the rear trigger members are arranged on both sides of the trigger gap for the fabric in pairs opposite one another and the knitted fabric between the front and rear exhaust members frictionally clamped and peelable by this, each of the trigger members against the fabric with an adjustable force can be applied and moved away from this, which is characterized in that each deduction process in and against the withdrawal direction of the knitted fabric is individually controlled movable, wherein the control of the movements of the individual take-off members in response to the control of the needle movement of the knitting machine takes place.

Also, the extraction device according to the invention is arranged immediately below the needle beds, so that the fabric can be detected and pulled as close as possible to the stitch formation area. The trigger arms of the trigger pull the knit frictionally between them and pull it off. This means that there is no roughening of the surface of the knitted piece. The gripping surfaces of the trigger members can be made of a corresponding material, for example a rubber-like material, to optimize the frictional engagement and / or have a suitable surface structure. Characterized in that the control of the movements of the withdrawal organs in dependence from the control of the needle movements, it can be ensured that for each stitch course or courses to be formed the optimal peel force is exerted on the fabric, ie neither too much nor too little tension is exerted on the fabric during the formation of the stitches.

It is advantageous if the movements of a pair of front and rear extraction members are synchronously feasible. In this way, the front and the back of the knit are equally acted upon by the trigger members. But it is also possible that either only the front or only the rear trigger members perform a trigger movement and the respective opposite trigger members are held in their uppermost position. This can be advantageous, in particular, in the case of knitted fabrics which consist entirely or partially of at least two knitted surfaces.

In a preferred embodiment, each of the trigger members can be moved by a predeterminable distance in the withdrawal direction, be durable in this position a predetermined period of time and then be moved back into a start-trigger position. The length of the distance in relation to the mesh length determines the withdrawal force. The period of time in which the extraction members remain in the lowest position must be sufficient to allow the withdrawal force to act until the stitch formation is completed safely. Subsequently, the trigger members can be moved back up to again exert a trigger force on the fabric can.

Further advantages arise when the extraction device extends over the entire length of the needle beds. The trigger device can then simultaneously develop a spreading effect on the fabric, ie the fabric is over its entire width constantly from the trigger device recorded so that the withdrawal forces act equally in all places.

For the precise control of the individual extraction members, it is advantageous if the front and rear extraction members are slidably mounted in grooves of front and rear guide beds in and against the withdrawal direction and against the fabric and away from it. The guide through the grooves allows a very precise and controlled movement of the individual trigger elements. These can also be moved to several parallel to each other, which always run individual groups of trigger organs synchronous movements.

In particular, in the arrangement of the trigger members in guide grooves of a guide bed, it is advantageous if the movements of the trigger members by means of control curves, engage in the arranged on the trigger members feet. The cams can not only control the linear movement of the trigger members in and against the withdrawal direction, but also the movement of the trigger members on the fabric to and from the fabric away. The movement of the cams over the guide beds can advantageously be coupled with the movements of the knitting cam which controls the needle movement.

In a particularly preferred embodiment, a number of juxtaposed upper and a number of juxtaposed lower front and rear take-off members may be provided, wherein the upper and lower take-off members are arranged alternately in the longitudinal direction of the needle beds. The front and rear extractors are thus divided into upper and lower exhaust organs, which alternate in each case. This opens up further possibilities for varying the initiation and exertion of pull-off forces on the knitted fabric.

It is advantageous if the gripping surfaces of the upper and lower take-off members are shaped such that the two rows of upper and lower take-off members each form almost closed, strip-shaped overall gripping surfaces. In this way it is ensured that uniform take-off ratios can be produced directly below the stitch formation area over the entire length of the needle beds.

The division into upper and lower trigger members offers particular advantages when first the upper trigger members are moved to their start trigger position before the lower trigger members are moved to their start-trigger position, so that the fabric is constantly clamped between the front and rear trigger members. This means that the fabric remains captured by the trigger during its entire production. As a result, the trigger device can also fulfill a spreading function for the knitted fabric.

Further advantages can be achieved if springs are provided for generating the pressing force of the trigger members against the fabric, wherein the spring force is adjustable. In this way, the required contact pressure of the draw-off elements on the fabric can be adapted to the knit properties, such as yarn quality and surface structure.

The safe operation of the trigger device can be increased by the fact that the linear and / or pivoting movements of the trigger members are limited. Malfunction and the exertion of excessive forces on the fabric are thereby excluded. Another measure in this direction is the provision of a fixation of the trigger members at least in their reached after the withdrawal movement withdrawal position. This can prevent that the trigger members during the deduction unintentionally move upwards and thereby reduce the pull-off force.

The invention also relates to a method for removing a knit fabric on a flat knitting machine in which the fabric is frictionally clamped and withdrawn below the needle beds of the knitting machine between the front and rear withdrawal members, wherein the pressure force of the trigger members adjusted according to the quality of the knitted fabric and each of the trigger members in and separately against the take-off direction of the knitted fabric and moved in response to the control of the needle movement of the knitting machine. It is advantageous if the fabric is kept constantly clamped between the front and rear exhaust members. This keeps the knitwear wide throughout its production.

Hereinafter, a preferred embodiment of a take-off device according to the invention will be described with reference to the drawings.

Fig. 1

einen Teilschnitt senkrecht zur Maschinenlängsachse einer Flachstrickmaschine mit einer Abzugsvorrichtung;

Fig. 2

eine Ansicht auf das hintere Führungsbett der Abzugsvor- richtung aus Fig. 1;

Fig. 3 - 7

der Fig. 1 entsprechende Schnittdarstellungen mit unter- schiedlichen Stellungen der Abzugsorgane der Abzugsvor- richtung aus Fig. 1;

Fig. 8

eine Ansicht eines Strickschlosses mit Markierung der Bewegungen der Abzugsorgane der Abzugsvorrichtung aus Fig. 1;

Fig. 9 - 12

der Fig. 3 entsprechende Schnittdarstellungen durch die Flachstrickmaschine mit Einsatz der Abzugsvorrichtung für unterschiedliche Gestricke.

In detail show:

Fig. 1

a partial section perpendicular to the machine longitudinal axis of a flat knitting machine with a trigger device;

Fig. 2

a view of the rear guide bed of the trigger Fig. 1 ;

Fig. 3 - 7

of the Fig. 1 corresponding sectional views with different positions of the trigger elements of the trigger device off Fig. 1 ;

Fig. 8

a view of a knitting lock with marking the movements of the trigger members of the trigger Fig. 1 ;

Fig. 9 - 12

of the Fig. 3 corresponding sectional views through the flat knitting machine with use of the trigger device for different knitted fabrics.

In the sectional view from Fig. 1 a withdrawal device 1 can be seen, which is formed symmetrically to a median plane 100 between the front needle bed 200 and the rear needle bed 201. The withdrawal device 1 is located relatively close below an intersection point 101 (needle cross), which form the undersides of the needles 300, 301 mounted in the two needle beds 200, 201 with each other. The withdrawal device 1 has at least the length of the needle beds 200, 201.

Below the front needle bed 200, a front guide bed 2 and below the rear needle bed 201, a rear guide bed 3 is arranged. In these guide beds 2, 3 grooves 21, 31 are incorporated over the entire length with the same width and depth and at the same distance from each other. The grooves 21 of the front guide bed 2 and the grooves 31 of the rear guide bed 3 are each in pairs opposite. In the grooves 21, 31 alternately upper take-off members 4, 4 'and lower take-off members 5, 5' are arranged, wherein in the respective correspondence grooves of the guide beds 2, 3 the same type of take-off members is arranged. In this way, an upper take-off member 4 of the front guide bed 2 is an upper take-off member 4 'of the rear guide bed 3 opposite. The same applies to the lower take-off organs 5, 5 'of the front guide bed 2 and the rear guide bed 3.

The in Fig. 1 Section shown extends through the guide beds 2, 3, that in the front guide bed 2 can be seen in a groove 21 in which an upper trigger member 4 is longitudinally movably and pivotally guided. In the rear guide bed 3 can be looked into a groove 31 in which a lower trigger member 5 'is mounted longitudinally movable and pivotable.

In the guide beds 2, 3 also round rods 22, 32 are mounted, of elongated holes 41, 51 of the upper and lower take-off members 4, 5; 4 ', 5' are encompassed. As a result, the trigger members 4, 5; 4 ', 5' fixed in the grooves 21, 31. In addition, the round rods 22, 32 form the axes for the pivoting movements of the take-off members 4, 5; 4 ', 5' and at the same time a mechanical limitation of their displacement along the grooves 21, 31. The uppermost position of the trigger members 4, 5; 4 ', 5' is reached when their slots 41, 51 abut with their surfaces 42, 52 on the round bars 22, 32. If, on the other hand, the surfaces 43, 53 of the elongated holes 41, 51 are in contact with the round rods 22, 32, then the extraction elements 4, 5; 4 ', 5' in their lowest position. The type of fixation of the trigger members 4, 5 shown here; 4 ', 5' in the grooves 21, 31 of the guide beds 2, 3 is merely exemplary. There are also other technical solutions conceivable.

The deduction organs 4, 5; 4 ', 5' each have joint discs 44, 54, on which gripping pieces 6, 6 'are fixed in such a way that they can perform pivoting movements around the circumference of the joint discs 44, 54, so that the gripping surfaces 61, 61' of the gripping pieces 6, 6 'At all the thicknesses of the knit piece 400 come to this over the entire surface to the plant.

The pivoting movements of the gripping piece 6 of the upper trigger slide 4, 4 'are limited by the abutment of the gripping piece edges 62, 63 on the surfaces 45, 46 of the take-off members 4, 4'. In the lower take-off members 5, 5 ', the pivoting movements of the gripping pieces 6' by the system of Greifstückkanten 62 ', 63' on the surfaces 55, 56 of the take-off members 5, 5 'limited. The gripping surfaces 61, 61 'of the gripping pieces 6, 6' have a high coefficient of friction due to their surface design and / or their material.

The take-off members 4, 5 of the front guide bed 2 can perform movements according to the arrow symbol 150 and the trigger members 4 ', 5' of the rear guide bed 3 according to the arrow symbol 150 '. The arrow U indicates the movement to the intersection point 101 (needle cross) and the arrow D the movement away from the needle cross 101. The arrow S symbolizes the pivoting movement for closing the gripping pieces 6 and the arrow O the pivoting movement for opening the gripping pieces 6.

In the front discharge members 4, 5, the movement in the direction of the arrow S is effected by the force of bending springs 7, which act on the legs 47, 57 of the take-off members 4, 5 with their top surface 70. In the case of the rear take-off elements 4 ', 5', the movement in the direction of the arrow S is effected in an analogous manner by means of bending springs 8, which act on the legs 47, 57 of the take-off members 4 ', 5' with their head surface 80. The bending springs 7, 8 are each secured to shafts 9, 10. The shafts 9, 10 are rotatably mounted in bearing pieces, not shown, which are advantageously connected to the guide beds 2, 3. The bending springs 7, 8 not only cause a pivoting movement of the trigger members 4, 5; 4 ', 5' in the direction of arrows S on the fabric 400, so that the gripping pieces 6, 6 'come to rest on the fabric 400, but they also determine the force with which the gripping pieces 6, 6' press on the fabric 400 , From this force, in turn, depends on the frictional force acting between the gripping surfaces 61 and the fabric 400 when opposing withdrawal means 4, 5; 4 ', 5' move together in the withdrawal direction D. From this frictional force, in turn, the withdrawal force, which introduces the force acting in the direction of arrow A clamping force in the fabric 400, so that a continuous and uniform mesh formation can take place.

The legs 47, 57 of the take-off members 4, 5 are advantageously designed such that the force of the torsion springs 7, 8 in each height position of the trigger members 4, 5 changed so that the gripping pieces 6, 6 'in each height position of the trigger members 4, the fifth Press against the fabric 400 with the same force.

Since knits can be formed of different materials and in different types of weaving, the manufacture of each knit fabric requires a peel force specific to each fabric section, advantageously for each knit series to be formed or at least for the knitting ranks formed during movement of the sled over the fabric width , should be adjustable. In the case of the draw-off device according to the invention, a change in the withdrawal force is achieved, for example, by the pressure force of the withdrawal members 4, 5; 4 ', 5' is changed. In the example shown, this can be effected by rotation of the shafts 9, 10 in the opposite direction by the same angle of rotation. An increase in the pressure force results when both shafts 9, 10 rotate in the direction of arrow P +, P '+, a reduction of the pressing force when they move in the direction of arrow P-, P'-. A change in the pressure force could also be achieved in that the contact position of the top surfaces 70, 80 of the torsion springs 7, 8, which have a constant spring force, on the legs 47, 57 of the take-off members 4, 5; 4 ', 5' is made variable.

On the side and over the length of the grooved portion of the front guide bed 2, a stop bar 11 and in a similar manner to the rear guide bed 3, a stop bar 12 is attached. At these stop strips 11, 12, the legs 47, 57 of the lower and upper take-off members 4, 5; 4 ', 5' to the plant when their gripping surfaces 61, 61 'have reached at least the area of the center plane 100. As a result, the center plane 100 next position of the trigger members 4, 5; 4 ', 5' mechanically limited. This type of limitation is merely exemplary.

The movement of the front extraction elements 4, 5 in the front guide bed 2 in the withdrawal direction D is effected by acting on feet 48, 58 of the take-off members 4, 5 by a control cam KD1. The rear take-off elements 4 ', 5' in the rear guide bed 3 are moved in the withdrawal direction D by acting on feet 48, 58 by means of a control cam KD2. The cams KD1, KD2 can be switched so that they either act on the feet 48, 58 or not act on them. In addition, the cams KD1, KD2 can be adjusted in the vertical direction, so that the trigger members 4,5; 4 ', 5' can be moved to any position within its vertical range of motion.

Preferably, the trigger members 4, 5; 4 ', 5', but at least the trigger members 5, 5 'in the respective height position, in which they were brought by the control cams KD1, KD2, as long as fixed, until over other cams, a movement in the opposite direction is introduced into it. The type of fixation is not shown here.

The movement of the front trigger members 4, 5 in the direction of the arrow U against the withdrawal direction D is by the admission of their Feet 48, 58 effected by a control cam KU1. In the rear take-off members 4 ', 5' this is effected by a control cam KU2. The cams KU 1, KU 2 can be designed so that the trigger members 4, 5; 4 ', 5' through them always in the starting trigger position, ie their highest position in which they are the needle cross 101 closest to be moved. In a preferred embodiment, first the feet 48 of the upper take-off members 4, 4 'are acted upon, thereby bringing the upper take-off members 4, 4' in the uppermost position. Subsequently, the feet 58 are acted upon by the control curves KU1, KU2 in order to bring the lower take-off members 5, 5 'up into the start-trigger position. As a result, the knitted fabric 400 always remains tensioned by the draw-off device 1 and is held wide by it.

Also for triggering the pivoting movement of the take-off members 4, 5; 4 ', 5' are provided control cams, here the cams KS1, KS2 for the upper take-off members 4, 4 'and the cams KS3, KS4 for the lower take-off members 5, 5'. In this case, the control cams KS1, KS2, KS3, KS4 each solve a movement of the take-off members 4, 5; 4 ', 5' away from the knit 400, d. H. in the direction of arrow O, off. The cams KS1, KS2, KS3, KS4 act on second feet 49, 59 of the trigger members 4, 5; 4 ', 5'. The pivoting movements of the trigger members 4, 5; 4 ', 5' are each introduced before the trigger members 4, 5; 4 ', 5' are moved to their uppermost position.

The cams KS1, KS2, KS3, KS4 can be switched in a preferred embodiment between an active position in which they act on the feet 49, 59 of the trigger members, and a passive position.

In normal operation, the front upper take-off members 4 move together with the upper rear take-off members 4 'located opposite them in the withdrawal direction D and counter to the withdrawal direction U. Also, the front and rear lower take-off members 5, 5' are normally moved synchronously. But it is also possible, via a certain withdrawal path, the upper and lower take-off members 4, 5; 4 ', 5' only one guide bed 2, 3 to move in the withdrawal direction D on the cams KD1, KD2. In this case, for the guide bed 2, 3, in which the trigger members 4, 5; 4 ', 5' should perform no withdrawal movement, one of the switchable control curves KH1 or KH2 be brought into operation. These then hold the trigger members 4, 5; 4 ', 5' in their starting take-off position, while the opposite take-off members 4, 5; 4 ', 5' perform their withdrawal movement in the direction D.

In a preferred embodiment, the cams KD1, KU1, KH1, KS1, KS3 move across the front guide bed 2 in synchronism with each knitting system causing movement of the needles 300 of the front needle bed 200. In an analogous manner, the control cams KD2, KU2, KH2, KS2, KS4 move along the rear guide bed 3 of the fume cupboard 1 in synchronism with each knitting system causing the movement of the needles 301 of the rear needle bed 201.

In the Fig. 1 Deduction device 1 shown is a preferred embodiment of a take-off device according to the invention. But it is also conceivable, for example, that the upper and lower take-off members 4, 5 only one guide bed 2, 3 to push the fabric 400 to a running over the entire length of the Nadelraumlänge slide bar and bring through their controlled withdrawal movements in the knitted fabric necessary for the stitch formation clamping force ,

In Fig. 2 is a plan view of a portion of the rear guide bed 3 from the center plane 100 of the knitting machine ( Fig. 1 ) seen from. The trigger members 4 ', 5' are in their uppermost position. It can be seen the introduced into the guide bed 3 grooves 31, which preferably all have the same distance from each other. In the grooves 31 lower take-off members 5 'and upper take-off members 4' are longitudinally movable and pivotally mounted in a continuous change. The trigger members 4 ', 5' carry gripping pieces 6, 6 ', which can perform a limited pivoting movement in relation to their vertical position. The gripping pieces 6, 6 'are shaped such that their gripping surfaces 61, 61' add up to an overall closed strip-shaped gripping surface 600 ', which is as long as the needle space length NRL and has a certain functional height FH.

The mutual distances of the individual gripping surfaces 61, 61 'should be limited to the technologically required level. The widths B, b of the gripping surfaces 61, 61 'can be chosen freely and quite correspond to the multiple of the mutual spacing of the knitting needles. The gripping surfaces 61, 61 'of the upper and lower take-off members 4', 5 'overlap. The height of the overlap HU is determined by technical requirements.

Throughout the withdrawal process, the upper take-off members 4, 4 'with their adjacent lower take-off members 5, 5' form a functional unit, which is referred to below as the reference numeral 50 for the front take-off members and the reference numeral 50 'for the rear take-off members. In the extraction device 1 lie on the front of the knitted fabric 400 ( Fig. 1 ) the total withdrawal surface 600 formed from the individual gripping surfaces 61, 61 'of the withdrawal members 4, 5 of the front guide bed 2 (FIG. Fig. 1 ) and at the back of the fabric 400 from the individual gripping surfaces 61, 61 'of the rear take-off elements 4', 5 'of the rear guide bed 3 Gesamtabzugsfläche 600' over the entire width of the knitted fabric 400 at. If, according to a preferred embodiment of the extraction device during the withdrawal process, first the front and rear upper and lower take-off members 4, 5; 4 ', 5', then the lower take-off members 5, 5 'alone, then abut the upper take-off members 4, 4' and at the end again the upper and lower front and rear take-off members on the fabric 400, the fabric 400 during the entire time of the trigger device 1 clamped. As a result, the withdrawal device 1 exerts an excellent spreading effect on the knitted fabric. This favors the knitting conditions mainly in the edge region of the knitted fabric. If the stitching operation is temporarily carried out only in individual regions of the knitted fabric 400, the predetermined tensioning force is introduced through the draw-off device 1 into the stitches of the needles which do not currently form stitches. The stitches of the needles forming stitches are peeled off, and the predetermined tension force is introduced for each stitch course to be formed.

The Fig. 3 - 7 show in one of the Fig. 1 Corresponding sectional view of the operation of the trigger device 1. The trigger device 1 provides for knits that are produced in one system, the possibility that acts for each knitting a predetermined withdrawal force. For knitted fabrics made with multiple knitting systems, all knitting lines created by the movement of the sled across the knitting width have the same given withdrawal force. It is, however, brought to individual effect for each knitting series. The movements of the trigger members 4, 5; 4 ', 5' and in particular the withdrawal function units 50, 50 'take place in dependence on the needle movements. Since the needle movements are initiated by knitting locks and the movements of the withdrawal function units 50, 50 'by control cams, work these cams in dependence and synchronous to the knitting locks. For each knitting lock a cam arrangement on the trigger device 1 is required. In the illustrated embodiment of the extraction device 1, the withdrawal process is dynamic. The functional units 50, 50 'exercise movements synchronously with the knitting locks over the entire width of the knitted fabric. In the Fig. 3 - 7 The sequence of movements of a trigger function unit 50 in the front guide bed 2 and the opposite trigger function unit 50 'in the rear guide bed 3 is now shown and described.

In Fig. 3 the withdrawal function units 50, 50 'are in their starting withdrawal position, ie in their uppermost position. With the by the rotational movement of the shafts 9, 10 in the direction of arrows P +, P '+ in the bending springs 7, 8 generated force, the gripping pieces 6, 6' of the upper and lower take-off members 4, 5; 4 ', 5' pressed against each other and hold the fabric 400 firmly. A tensioning force in the direction of the arrow A, which is optimally selected for the next stitching operation, is introduced into the knitted fabric 400. This clamping force in the fabric 400 also exerts on the trigger members 4, 5; 4 ', 5' a force upwards. However, the movement of the trigger members 4, 5; 4 ', 5' limited upwards by the surfaces 42, 52 of the front and rear take-off members 4, 5; 4 ', 5' come to the rods 22, 32 to the plant.

The gripping pieces 6 of the upper take-off members 4, 4 'press with their entire gripping surface 6' against that part of the knitted fabric 400 to which a clamping force in the direction of the arrow A acts. In contrast, press the gripping pieces 6 'of the lower trigger members 5, 5' only with the upper half of the gripping surfaces 61 'on the region of the fabric 400 in which the clamping force acts. In contrast, the lower half of the gripping surfaces 61 'presses against a stress-free part of the knitted fabric 400. The withdrawal function units 50, 50 'remain in this highest position, the starting take-off position, during the entire needle-pulling movement, where the stitch of the existing course slides behind the needle-tongue, and during the needle-retracting motion, in which first the thread for the stitch of the next stitch-forming operation in the needle-hook is inserted, the stitch of the existing course over the needle head is cut off and the next stitch is calculated in the desired size.

In Fig. 4 the trigger units 50, 50 'are in their lowermost position. This position is an extreme position and can only be taken on very coarse pitched knit fabrics and special throw-off lines. In other crocheted ends the movement of the trigger members 4, 5; 4 ', 5' already above. For monofilament-formed knits, a special pull-off force can be specified for each stitch row before the beginning of each stitch row. In the case of multi-layered knitted fabrics, a withdrawal force can be predetermined before the beginning of the first course, which is constant for all courses that are formed in the same slide pass, but is initiated individually for each of the rows of knits. The specification of the withdrawal force is effected as follows: Before the withdrawal function units 50, 50 'carry out their joint movement in withdrawal direction D, the pressure force is applied to the gripping pieces 6, 6', which is necessary to reduce the frictional force between the gripping surfaces 61, 61 '. and to achieve the fabric 400, which corresponds to the predetermined withdrawal force. As a result of this pull-off force, the tension force acting in the direction of the arrow A is generated in the knitted fabric 400, which is necessary for optimum stitch formation. Before each new slide passage, the pull-off force can be increased or decreased by turning the shafts 9, 10 and thus optimally adapted to the pattern of the knitted fabric.

The trigger function units 50, 50 'can by the cams KD1, KD2, the feet 48, 58 of the trigger members 4, 5; 4 ', 5', in any position within the range between the start trigger position and the in Fig. 4 shown lowest position. In this case, at least the lower take-off members 5, 5 'can be fixed in this position until they are moved by other cams against the withdrawal position D.

Normally, the travel distance of the take-off function units 50, 50 'corresponds to the length of the stitch formed in the current stitching operation, plus an overpath that depends primarily on the type of weave of the knitted fabric and the material of the knitting yarn. The distance of movement of the withdrawal function units 50, 50 'can also be shorter than in the normal case. This is one way to reduce the tension in the fabric 400 for each stitching operation. The movement of the extraction units 50, 50 'in the direction of the arrows D begins as soon as the stitches of the instant stitch formation process are formed to their desired size, and ends at the latest when the needles with the stitches of the course formed in this stitch formation process are again in their home position ,

Fig. 5 shows the deduction organs 4, 5; 4 ', 5' in the same height position as in Fig. 4 , The upper take-off members 4, 4 'are acted upon at their feet 49 by the cams KS1, KS2. As a result, the upper take-off elements 4, 4 'lead around the round bars 22 and 32, respectively, from a pivoting movement in the direction of the arrows O. As a result, the gripping pieces 6 of the take-off members 4, 4 'are lifted off the fabric 400. The clamping force in the fabric 400 is now held only by the gripping pieces 6 'of the lower take-off members 5, 5'.

By applying the feet 48 of the upper trigger slide 4, 4 'by means of the control curves KU1, KU2 the upper trigger slides 4, 4' are brought in the direction of arrows U in their uppermost position. During this movement, the feet 49 of the upper take-off members 4, 4 'are acted upon by the control cams KS1, KS2. The opening movement and the subsequent movement of the upper take-off members 4, 4 'in their uppermost position begin at the earliest when the needles, which have formed stitches in this stitch forming operation, are again in their basic position.

Fig. 6 shows the upper take-off members 4, 4 'in their uppermost position. However, they have now been moved against the fabric 400 again and press against this with the force generated by the bending springs 7, 8. The lower take-off members 5, 5 'are unchanged in their lowest position and press with unchanged force against the fabric 400th

In Fig. 7 are those of the lower and upper deduction organs 4, 5; 4 ', 5' formed withdrawal function units 50, 50 'in the same height position as in Fig. 6 , However, now the lower take-off members 5, 5 'acted on their feet 59 by the cams KS3, KS4. As a result, the lower trigger slides 5, 5 'pivot about the rods 22 and 32 in the direction of the arrows O to the outside and are lifted from the fabric. The region 400 'of the fabric 400 below the gripping pieces 6 of the upper take-off members 4, 4' is characterized without clamping force. In the knitted area above, however, the necessary for the stitch formation clamping force in the direction of arrow A prevails unabated, which is effected by the upper take-off members 4, 4 '.

By the action of their feet 58 by means of the control curves KU1, KU2, the lower take-off members 5, 5 'are brought in their uppermost position in the direction of the arrows U. During this movement, the feet 59 of the lower take-off members 5, 5 'remain loaded by the cams KS3, KS4, ie the lower take-off members 5, 5' remain lifted from the knitted fabric 400. As soon as the lower take-off members 5, 5 'have reached their uppermost position, the bending springs 7, 8 push the take-off members 5, 5' back against the knitted fabric. The upper halves of the gripping pieces 6 'press on a part of the knitted fabric 400 in which a clamping force acts in the direction of the arrow A, while the lower halves of the gripping pieces 6' press on a tension-free part of the knitted fabric 400. As soon as the gripping pieces 6 of the lower take-off elements 5, 5 'rest against the fabric 400 again, the withdrawal function units 50, 50' are in the in Fig. 1 described position. The opening movement of the lower take-off members 5, 5 'and their subsequent movement into the uppermost position begin as soon as the upper take-off members 4, 4' are in their uppermost position and rest against the fabric again.

Fig. 8 shows a knitting lock 500, wherein in the figure in each case the beginning and the end of the associated movements of the lower and upper take-off members 4, 5; 4 ', 5', as in the Fig. 3 - 7 have been described, are shown.

The area NBM between the point N1 and the point N4 denotes the needle movement to form a loop when the knitting cam 500 moves in the direction of arrow V. The area ABM between the points A1, A5 denotes the deduction movement for the stitch formed in this course and for the stitch to be made in the next course.

At the point N1 coinciding with the point A1, the needles receive a propelling movement by the ejection member 501. By the upper take-off members 4, 4 'of the haul-off device 1, a tension force is introduced into the fabric, which is optimal for the stitches to be formed of this course series.

At point N2, the needles have reached their most advanced position and are brought into their return movement by a limit member 502. At the same time, the lower take-off elements 5, 5 'are moved into their uppermost position in the area between A1 and A2 (cf. Fig. 7 ). At point N3, the needles have been withdrawn by the needle punch 503 in accordance with the size of the loop formed. Immediately thereafter, a propelling movement is initiated by the ejection member 504 in the needles. In parallel, in the region between the points A2 and A3, the lower trigger slides 5, 5 'are pivoted against the fabric ( Fig. 3 ). Between the points A3 and A4, the withdrawal force is generated by the withdrawal device, which forms the tension in the fabric, which is optimal for the formation of the stitch of the next row of knitting. The trigger units 50, 50 'move down to a position which is a predetermined distance from their start trigger position ( Fig. 4 ). At point N4, which corresponds to point A4, the needle is in its home position. In the area between points A4 and A5, the upper take-off members 4, 4 'are pivoted away from the fabric and moved to their uppermost position. After reaching this position, they are swung back to the fabric ( Fig. 5 . Fig. 6 ).

The Fig. 9 - 12 show different knits. The loading of the feet 48, 58 of the upper and lower take-off members 4, 5; 4 ', 5', which form the withdrawal function units 50, 50 ', when viewed through the downward Movement of the withdrawal function units 50, 50 ', the withdrawal force is to be generated, which causes the optimal mesh formation for the clamping force in the direction of arrow A in the fabric 400. The representation corresponds to that in Fig. 3 shown situation.

In Fig. 9 a knitted fabric consisting of a knit surface 400 is shown, which is formed with needles 300, 301 of the front and back needle bed 200, 201. The simultaneous movement of the front and rear extraction members 4, 5; 4 ', 5' and thus the front and rear extraction function units 50, 50 'is done by the application of the feet 48, 58 of the take-off members 4, 5; 4 ', 5' by means of the control cams KD1, KD2.

In Fig. 10 a knitted fabric consisting of a knitted surface 400 is shown, which is formed with needles 301 of the rear needle bed 201. The movement of the extraction units 50, 50 'is identical to that in FIG Fig. 9 shown movement.

The also consisting of a knitted surface 400 knitted fabric in Fig. 11 is formed with needles 300 of the front needle bed 200. Again, the movement of the withdrawal function units 50, 50 'is identical to that in FIG Fig. 9 shown movement.

In Fig. 12 however, the knit consists of a knit surface 400 formed with needles 300 on the front needle bed 200 and a knit surface 401 formed with needles 301 on the back needle bed 201.

If the same number of knitted rows are formed in the same slide movement across the width of the knitted fabric for both knitted surfaces 400, 401, the movement of the withdrawal function units 50, 50 'is identical here as well Fig. 9 , If, on the other hand, one or more rows of stitches are formed only for one knitted surface 400, 401, then the withdrawal members which are in contact with this knitted surface must execute the withdrawal movements and their opposite withdrawal members must be held in their uppermost position. In the example shown in this figure, 200 rows of stitches for the knitted surface 400 are formed with needles 300 of the front needle bed 200. The front extractors 4, 5 must perform a movement in the direction of arrow D. Therefore, the feet 48, 58 of the front take-off members 4, 5 are acted upon by the control cams KD1. The rear take-off organs 4 ', 5', however, must remain in their uppermost position and are held by the application of their feet 48, 58 by means of the control curves KH2 in this position.

Claims (14)

1. A flat knitting machine comprising a knitted fabric take-off device having a plurality of front take-off elements (4, 5) arranged below the front needle bed (200) and having a plurality of rear take-off elements (4', 5') arranged below the rear needle bed (201), wherein the front and the rear take-off elements (4, 5; 4', 5') are arranged on both sides of the take-off gap for the knitted fabric (400) and oppose each other in pairs and the knitted fabric (400) can be clamped in a frictionally engaged manner between the front and the rear take-off elements and can be taken off by the same, and wherein each of the take-off elements (4, 5; 4', 5') can be placed with an adjustable force against the knitted fabric (400) and can be moved away from the same, characterized in that each take-off element (4, 5; 4', 5') can be moved individually controlled in and against the take-off direction (D) of the knitted fabric (400), wherein the control of the movements of the individual take-off elements (4, 5; 4' 5') takes place depending on the control of the needle movement of the knitting machine.
2. The flat knitting machine according to claim 1, characterized in that the movements of a pair of front and rear take-off elements (4, 5; 4' 5') can be carried out synchronously or in each case only one take-off element (4, 5; 4', 5') of a pair of front and rear take-off elements (4, 5; 4'5') can be moved.
3. The flat knitting machine according to claim 1 or claim 2, characterized in that each of the take-off elements (4, 5; 4', 5') can be moved by a predefinable distance in the take-off direction (D), can be kept in this position for a predefinable time and can subsequently be moved back in a start take-off position.
4. The flat knitting machine according to any one of the preceding claims, characterized in that the take-off device for knitted fabric extends over the entire length of the needle beds (200, 201).
5. The flat knitting machine according to any one of the preceding claims, characterized in that the front and the rear take-off elements (4, 5; 4', 5') are mounted in grooves of front and rear guide beds (2, 3) so as to be displaceable in and against the take-off direction (D) and pivotable toward the knitted fabric (400) and away from the same.
6. The flat knitting machine according to any one of the preceding claims, characterized in that the movement of the take-off elements (4, 5; 4', 5') is carried out by means of control cams (KD1, KD2, KU1, KU2, KH1, KH2, KS1 - KS4) with which legs (48, 58, 49, 59) engage which are arranged on the take-off elements (4, 5; 4', 5').
7. The flat knitting machine according to any one of the preceding claims, characterized in that a row of upper (4, 4') front and rear take-off elements arranged side by side and a row of lower (5, 5') front and rear take-off elements arranged side by side are provided, wherein the upper and lower take-off elements (4, 4'; 5, 5') are each arranged alternately in the longitudinal direction of the needle beds (200, 201).
8. The flat knitting machine according to claim 7, characterized in that the gripping surfaces (61, 61') of the upper and lower take-off elements (4, 5; 4', 5') are shaped in such a manner that the two rows of upper and lower take-off elements (4, 5; 4', 5) each form nearly closed, strip-shaped total gripping surfaces (600, 600').
9. The flat knitting machine according to claim 7 or claim 8, characterized in that first the upper take-off elements (4, 4') can be moved into their start take-off position before the lower take-off elements (5, 5') can be moved into their start take-off position so that the knitted fabric (400) is permanently clamped between front and rear take-off elements (4, 5; 4', 5').
10. The flat knitting machine according to any one of the preceding claims, characterized in that springs (7, 8) are provided for generating the pressing force of the take-off elements (4, 5; 4', 5') against the knitted fabric (400), wherein the spring force of the springs (7, 8) is adjustable.
11. The flat knitting machine according to any one of the preceding claims, characterized in that the linear movements and/or pivoting movements of the take-off elements (4, 5; 4', 5') are limited.
12. The flat knitting machine according to any one of the preceding claims, characterized in that the take-off elements (4, 5; 4' 5') can be fixed at least in their take-off positions reached after the take-off movement.
13. A method for taking-off a knitted fabric on a flat knitting machine by means of which, below the needle beds of the flat knitting machine, the knitted fabric is clamped in a frictionally engaged manner and taken-off between the front and rear take-off elements, wherein the pressing force of the take-off elements is adjusted according to the quality of the knitted fabric, characterized in that each of the take-off elements is moved in and against the take-off direction of the knitted fabric in an individually controlled manner and depending on the control of the needle movement of the knitting machine.
14. The method according to claim 13, characterized in that the knitted fabric is permanently kept clamped between front and rear take-off elements.

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