EP2000571B1 - Sewing machine and method for operating such a sewing machine - Google Patents

Description

The invention relates to a sewing machine with a transport device for the intermittent feed of sewing material according to the preamble of claim 1. Furthermore, the invention relates to various operating methods for such a sewing machine.

A sewing machine of the type mentioned is known from the EP 0 512 145 B1 , There, a stitch length adjustment is described by corresponding change of feed values of an upper and a lower conveyor.

From the US 4,867,082 is a sewing machine with an upper feed dog and two lower conveyors known. A transport feed of the upper transporter can be adjusted via an adjusting device with an actuator and a guided holder. Feed lengths of the two lower conveyors can be adjusted via corresponding actuators. The actuators for the upper feed dog and the lower feeders each have an adjustment motor. The actuators of the upper conveyor and the lower conveyors are in signal communication with a controller to which a memory belongs. Stored setting data are used to control the actuators of the upper conveyor and the lower conveyors during the execution of a sewing sequence.

From the DE 10 2004 019 001 A1 a differential feed sewing machine is known.

Many, especially demanding sewing tasks require a more flexible adaptation of the Nähgutvorschubs to the respective sewing conditions, as can be ensured by the known sewing machines.

It is therefore an object of the present invention, a sewing machine of the type mentioned in such a way that the flexibility of the Nähgutvorschubs is increased to adapt to different sewing requirements.

This object is achieved by a sewing machine with the features specified in claim 1.

According to the invention it has been recognized that it is possible to automate the already known mechanism for changing the feed length of a lower and an upper conveyor by the use of appropriate adjustment drives. The feed length change can now take place by controlling the corresponding adjustment drive via the control device. The control device can be in signal communication with external sensors and / or enable direct influencing of the adjusting drives by operating elements of the sewing machine, for example foot switches, toggle levers or pushbuttons. In this way, a flexible adaptation of the Nähgutvorschubs, for example, to the course of a seam, possible. For example, the stitch length in the corner between two abutting seams can be adjusted so that the stitch ends in the corner without the last stitch needing to be different in length from previous stitches. By means of the control device, such a feed length adjustment can take place over an entire sewing sequence, wherein in each case the corresponding setting data for the adjusting drives are called up. Also an adjustment of the feed Changing sewing material parameters, for example a changing composition of the fabric or a change in the sewing direction relative to the angle of the warp and weft threads of the sewing material, are possible. In addition to an automatic specification of different total feed lengths, ie different stitch lengths, a different ratio of the feed lengths between the upper and the lower feed dog can also be specified, which is also referred to below as the Raff feed value. The change in the feed length can also be used to achieve desired optical effects during sewing. The mechanical top feed adjusting device and the mechanical bottom feed adjusting device are designed as link adjustments and have at least one adjusting device adjustable along the adjusting link. Such gate adjustments as adjusting devices have proven themselves because of their mechanical robustness. At least one of the adjusting devices has a rotatably driven via the associated adjustment cam plate having a peripheral surface with varying radius in peripheral sections, with the peripheral surface of an adjusting body sections to Vorschublängeverstellung cooperates, which is mechanically coupled to the associated feed dog. Such adjustment can be structurally integrated into a sewing machine with little effort.

In a sewing machine according to claim 2, not only the length or the ratio of the feed length of the upper conveyor to the feed length of the lower conveyor set, but it can also adjust the feed lengths of the two lower conveyors with each other. This is also referred to below as a specification of different crimp feed values. By the additional and controllable via the control device bottom feed adjustment can the flexibility in the specification of feed options by the sewing machine according to the invention further increase.

A stepper motor according to claim 3 allows a finely predetermined feed adjustment.

An accommodation of the adjusting drive according to claim 4 leads to a compact sewing machine.

An embodiment according to claim 5 enables an automatic adjustment of the thread tension, in particular to a predetermined length of the control device stitch length.

Another object of the invention is to provide operating methods for the sewing machine according to the invention.

This object is achieved by the operating method according to claims 6 and 7 and, as regards the sewing machine according to claim 2, by an operating method according to claim 8.

The advantages of these operating methods correspond to those which have already been explained above with reference to the sewing machine according to the invention.

Fig. 1

eine Seitenansicht einer Nähmaschine mit einer Grundplatte;

Fig. 2

eine Aufsicht auf die Nähmaschine nach Fig. 1;

Fig. 3

eine Unteransicht der Nähmaschine nach Fig. 1;

Fig. 4

eine stirnseitige Ansicht der Nähmaschine gemäß Blickrichtung IV in Fig. 3;

Fig. 5

einen Schnitt gemäß Linie V-V in Fig. 3;

Fig. 6

einen Schnitt gemäß Linie VI-VI in Fig. 2;

Fig. 7

einen Schnitt gemäß Linie VII-VII in Fig. 3;

Fig. 8

eine Seitenansicht der Grundplatte aus der gleichen Blickrichtung wie Fig. 1, wobei im Vergleich zur Fig. 1 mechanische Komponenten fehlen, sodass die mechanische Kopplung einer mechanischen Untertransport-Verstelleinrichtung verbleibt, wobei diese Untertransport-Verstelleinrichtung in der Stellung "großer Hub" vorliegt;

Fig. 9

einen Schnitt gemäß Linie IX-IX in Fig. 8;

Fig. 10

eine zu Fig. 8 ähnliche Ansicht mit der Untertransport-Verstelleinrichtung in der Stellung "kleiner Hub",

Fig. 11

einen Schnitt gemäß Linie XI-XI in Fig. 10; und

Fig. 12

vergrößert einen Ausschnitt aus Fig. 4, wobei insbesondere die Transporteure zum Nähgutvorschub dargestellt sind.

An embodiment of the invention will be explained in more detail with reference to the drawing. In this show:

Fig. 1

a side view of a sewing machine with a base plate;

Fig. 2

a top view of the sewing machine Fig. 1 ;

Fig. 3

a bottom view of the sewing machine after Fig. 1 ;

Fig. 4

an end view of the sewing machine according to viewing direction IV in Fig. 3 ;

Fig. 5

a section along line VV in Fig. 3 ;

Fig. 6

a section according to line VI-VI in Fig. 2 ;

Fig. 7

a section according to line VII-VII in Fig. 3 ;

Fig. 8

a side view of the base plate from the same direction as Fig. 1 , in comparison to Fig. 1 mechanical components are missing, leaving the mechanical coupling of a mechanical bottom feed adjusting device, this bottom feed adjusting device being in the "high lift"position;

Fig. 9

a section along line IX-IX in Fig. 8 ;

Fig. 10

one too Fig. 8 similar view with the bottom feed adjusting device in the "small stroke" position,

Fig. 11

a section along line XI-XI in Fig. 10 ; and

Fig. 12

enlarges a section Fig. 4 , wherein in particular the conveyors are shown for Nähgutvorschub.

A sewing machine 1 has an arm 2, a base plate 3, and a stand 3a connecting them. The free end of the arm 2 carries a head 4. In the arm 2, an arm shaft 5 is mounted, which is rotatably driven by a main drive not shown in detail. About the arm shaft 5 a mounted in the head 4 needle bar 6 is vertically moved up and down. At the lower end of the needle bar 6, a needle 7 is mounted. During operation of the sewing machine 1, the needle 7 passes through a stitch hole in a throat plate 8, which is inserted into a support plate 9 of the base plate 3. Below the needle plate 8 a co-operating with the needle 7 for looping gripper is arranged, which is driven by a gripper shaft and a deflection gear, which are not shown in detail. The drive of the gripper is also derived from the arm shaft 5. For fixing the sewing material in the stitch formation is a fabric presser 11, which is mounted at the lower end of a Stoffdrückerstange 12.

For intermittent feed of the material in a sewing direction 13, with an arrow in the Fig. 12 is shown and in the Fig. 12 extends from right to left, serves a transport device 14, whose frictionally cooperating with the material conveyors increased in the Fig. 12 are shown. With an upper surface of the fabric acts an upper Transporter 15 together, in the Fig. 12 on the one hand shown in a zero position and on the other hand at 15 'in one of these opposite to the left displaced maximum stroke position.

With a bottom of the fabric come two lower conveyors, namely a first lower conveyor 16 and a second lower conveyor 17 in contact. The first lower feed dog 16 is in the Fig. 12 left and the second lower conveyor 17 is in the Fig. 12 shown on the right. The two lower transporters 16, 17 have along the sewing direction 13 spaced-apart contact portions for frictional feed contact with the fabric underside. The transporters 16, 17 are shown on the one hand in a zero position and on the other hand at 16 ', 17' in a relation to this left displaced maximum stroke position.

For intermittently frictional feed contact with the sewing material, the transporters 15 to 17 each have a sawtooth profiling 18a.

The stroke of all three transporters 15 to 17 in the sewing direction can be set individually for each of the transporters 15 to 17 controlled. This will be described below in connection with the feed length of one of the lower transporters 16, 17 on the basis of Fig. 7 to 11 explained.

To adjust the feed length is a first stepper motor 18 which is fixedly mounted on the base plate 3. The first stepper motor 18 is operatively connected to the first lower feed dog 16. Connected to a drive shaft of the first stepping motor 18 in a rotationally fixed manner is a contact body 19 with a spiral-shaped outer peripheral abutment wall 20. The abutment wall 20 thus has a radius varying in circumferential sections. The contact body 19 is a driven rotatable cam. The abutment wall 20 abuts an adjusting or counter body in the form of a needle bearing 21, which is held in a fork-shaped deflecting rod 22. The needle bearing 21 thus represents a sliding body for cooperation with the abutment wall 20. The deflection bar 22 is connected via a hinge 23 with a link adjusting body 24, which in turn is rotatably connected to a slotted guide 25. Along the latter is a sliding block 26 displaced. This is in turn connected to a triangular lever 27. About an eccentric shaft 28 of the triangle lever 27 is vibrated. Depending on the guide direction of the slotted guide 25, this vibration is implemented in a more or less large torsional vibration of a transmission shaft 29 about its longitudinal axis.

The Fig. 7 and FIGS. 10 and 11 show a lower feed adjusting device 30, to which the first stepping motor 18 belongs, in a "small lift" position in which practically no angular displacement is transmitted to the transmission shaft 29 during operation. When operating the sewing machine, the assigned lower transporter remains virtually in its zero position. In the "small stroke" position, the outermost end of the abutment wall 20 bears against the needle bearing 21, so that the latter is maximally spaced from the drive shaft of the first stepping motor 18.

The 8 and 9 In contrast, show the position "long stroke" of the first lower feed adjustment 30. In this position "large stroke" the abutment wall 20 is at its innermost end on the needle bearing 21, so that the distance between this and the drive shaft of the stepping motor 18 is low. Between the two positions "small stroke" and "large stroke" is a relative rotation of the drive shaft of the first Stepping motor 18 of about 225 °. Since the stepper motor 18 has a high step resolution, all intermediate positions between the positions "small stroke" and "large stroke" can be practically infinitely preset.

In the position "long stroke" of the sliding block 26 in the slide guide 25 in a in the Fig. 9 approximately guided at a 45 ° angle obliquely upwardly extending guide direction. As a result, a maximum rotational angle adjustment is transmitted to the transmission shaft 29. The associated lower feed dog is then between the stitches between the zero position and the respective, in the Fig. 12 shifted position shown "big stroke".

In intermediate positions of the first lower feed adjustment device 30 between the illustrated positions "small stroke" and "large stroke" is correspondingly moved the first lower feed dog 16 between its zero position and a position between the zero position and the "large stroke" position. Between in the Fig. 12 shown maximum feed and the feed zero, depending on the position of the first stepping motor 18 and all intermediate positions are possible.

A second lower transport adjustment device 31 is used for controlled specification of the feed length of the second lower conveyor 17. The second lower transport adjustment device 31 has a second stepper motor 32, which is also mounted on the base plate 3 under the support plate 9. The second stepper motor 32 is operatively connected to the second lower feed dog 17. The mechanical actuation of the second lower feed adjusting device 31 corresponds to that of the first lower feed adjusting device 30 and has the same structure as this, with the difference that the second Untes transport adjustment device 31 on a transmission shaft 33 acts, which runs in the executed as a hollow shaft transmission shaft 29 of the first lower feed adjustment device 30 and is rotated independently of this about a common longitudinal axis of the two shafts 29, 33 by a predetermined angular amount to the feed control.

The transmission shafts 29, 33 act independently of one another on each of the lower conveyors 16 and 17. In this case, the feed length of the lower feed conveyor controlled by the second lower feed adjusting device 31 can be preset via the rotation of the second stepping motor 32, as described above in connection with FIG the first lower feed adjusting device 30 has been explained.

The Fig. 5 shows the second lower feed adjusting device 31 in a position similar to that of the first lower feed adjusting device 30 after the 10 and 11 corresponds, ie in the position "small stroke". By rotation of the second stepping motor 32, the second lower feed adjusting device 31 can be practically continuously changed to the "long stroke" position.

To adjust a feed length of the upper conveyor 15 is an upper transport adjustment 34. This has a third stepper motor 35, which is also mounted on the base plate 3 and mounted under the support plate 9. The third stepping motor 35 is in operative connection with the upper conveyor 15. The mechanical transmission from the stepping motor 35 to the upper feed dog 15 corresponds to that which has been explained above with reference to the two lower feed adjusting devices 30, 31. In contrast to the lower transport adjusting devices 30, 31, the upper transport adjusting device 34 has as a transfer member between the needle roller bearing 21 and the guide adjusting body 24 a pull rod 36, which extends in the stator 3a. Depending on the rotational position of the third stepping motor 35, a corresponding angular displacement is imparted to a transmission shaft 37 of the top feed adjusting device 34, which in turn is mechanically connected to the upper feed dog 15 via a push rod 37a. The transmission shaft 37 runs along the arm 2.

The three stepper motors 18, 32, 35 are all housed within a housing surrounding the base plate 3 and not shown in the drawing of the sewing machine.

One in the Fig. 1 schematically indicated control device 38 is connected to the two lower feed adjustment devices 30, 31 and the upper transport adjustment device 34 in signal connection. The control device 38 has a memory device 39, in which data to be processed sewing sequences and this sewing sequence data associated adjustment data for controlling the stepper motors 18, 32, 35 are stored during the execution of the sewing sequence.

• Zum einen lassen sich die Vorschublängen aller drei Transporteure 15 bis 17 synchron zueinander jeweils in gleicher Weise verstellen, sodass alle drei Transporteure 15 bis 17 von einer ersten gemeinsamen Vorschublänge hin zu einer zweiten gemeinsamen Vorschublänge verstellt werden. In diesem Fall wird also der gesamte Transport-Vorschub der Nähmaschine 1 und damit die Stichlänge verändert.

Due to the independent adjustment of the feed lengths of the transporters 15 to 17 on the adjusting devices 30, 31 and 34 can be realized adjustment, which include the following main adjustment options:

• On the one hand, the feed lengths of all three transporters 15 to 17 can be adjusted in synchronism with each other in the same way, so that all three transporters 15 to 17 are adjusted from a first common feed length to a second common feed length. In this case, therefore, the entire transport feed of the sewing machine 1 and thus the stitch length is changed.

Secondly, it is possible to adjust the feed of the two lower conveyors 16, 17 synchronously with each other, wherein the feed length of the upper conveyor either remains constant or changed by a change of the feed length of the lower conveyors 16, 17 different amount. Such an adjustment thus changes the difference between the transport paths realized during a transport stroke, on the one hand, of the lower transporters 16, 17 and, on the other hand, of the upper transporter 15. This is referred to below as the differentiability of the transport of the sewing machine 1 or as a change in the Raff feed value. By means of this differentiability, a change in the gathering of an upper workpiece part, which is transported by the upper conveyor 15, relative to a lower workpiece member, which is transported by the lower conveyors 16, 17, can be achieved.

Third, it is possible to adjust only the feed lengths of the two lower conveyors 16, 17 relative to each other. As a result, a change in a crimping of a lower workpiece part caused by the lower conveyors 16, 17 during transport can be varied. This adjustable property of the Nähguttransports by the sewing machine 1 is hereinafter referred to as differential or as a change of the Kräusel feed value.

Any overlays of these three basic adjustment options "change the feed length", "differentiability" and "differential" are possible.

In a first exemplary operating method of the sewing machine 1, a first feed value for advancing the material to be sewn by the transporters 15 to 17 is initially predetermined by corresponding synchronous control of all three stepper motors 18, 32, 35, controlled by the control device 38. Subsequently, the sewing material, as long as this first default value is set, so with a first stitch length, sewn. Subsequently, a second, from the first different feed value to the material feed with the transporters 15 to 17 by concurrently driving the stepper motors 18, 32, 35 predetermined. Subsequently, the sewing material is sewn with the resulting second feed value, which may for example be greater than the first feed value, so that the subsequent seam has a greater stitch length than before.

This controlled conversion of the feed value can be done, for example, depending on detected signal values of additional sensors on the sewing machine 1, for example a light barrier sensor or a touch sensor, which detects when one end of the material is reached and therefore only a few stitches are to be sewed to the seam end, so that it is ensured by appropriate adjustment of the stitch length that the last stitch ends at a predetermined location, without this last stitch in its length being too different from the previous stitches. Such a difference is undesirable for optical reasons. Even when sewing corner stitching this can be a stitch shortening can be prevented in the corner.

Depending on the specified stitch length, the thread tension is automatically adjusted, controlled by the control device 38. For this purpose, the control device 38 controls an electronic thread tension transmitter of the sewing machine 1. In this case, the thread tension is increased in particular as the stitch length is increased.

In a further, alternatively or additionally usable operating method for the sewing machine 1, the differentiability is utilized. Here, first, a first Raff feed value for advancing the material to be conveyed with the transporters 15 to 17, wherein the upper conveyor 15 z. B. makes a material feed, which is different from the Nähgutvorschub the lower conveyors 16, 17. Subsequently, the fabric is sewn with this first Raff feed value. Subsequently, by appropriate adjustment of either the stepping motor 35 for the upper conveyor 15 or concurrent adjustment of the stepper motors 18, 32 for the two lower conveyors 16, 17, a second, predetermined by the first Raff feed value. This can for example be done so that the difference in the feed between the upper conveyor 15 and the two lower conveyors 16, 17 is greater than before at the second Raff feed value. Now the fabric is gathered harder during the subsequent sewing than before. This can be used, for example, to achieve desired optical results during sewing or to compensate for a change in the shirring behavior of the fabric, for example when sewing seams with a change in direction for fabrics with preferred friction directions.

In a further method of operation, which can be performed alternatively or in addition to the above-mentioned operating method in the sewing machine 1, the differential is utilized. This is first a first crimp feed value for advancing the material to be sewn with the two lower transporters 16, 17, wherein z. B. the first lower feed dog 16 performs a Nähgutvorschub different from the Nähgutvorschub the second lower conveyor 17. In particular, at the first crimp feed value, the feed supplied by the second lower feed dog 17 is slightly larger than that supplied by the first lower feed dog 16. The fabric is now sewn with this first crimp feed value. Subsequently, by appropriate driving, for example, one of the two stepper motors 18, 32 for the lower conveyors 16, 17, a second crimp feed value is predetermined, which differs from the first crimp feed value. The conversion can for example be such that the difference in the feed between the two lower conveyors 16, 17 is now greater than before, so that the lower work piece is now crimped by the two lower conveyors 16, 17 more. Subsequently, the fabric is sewn with the second crimp feed value. This third method of operation can also be used to achieve certain optical results when sewing or to compensate for a change in the properties of the material during sewing, in particular when sewing seams with changes in direction.

Changes in sewing material parameters, which can be accommodated by changing the differentiability or the differential, are, for example, changes in the type of binding of the sewing material, changes in the raw material composition of the sewing material or changes in the degree of twist of the warp and weft threads with each other.

The control of the stepper motors 18, 32, 35 can automatically by the controller 38 when executing a sewing program or a Sewing sequence done. Alternatively or additionally, it is possible to enable this control directly, for example via a foot switch or a toggle or a button by the operator. The operator can therefore change the stitch length, the differentiability or the differential as needed during sewing. Such a direct control is possible in particular for making quick corrections, which is often desirable, for example, when sewing in sleeves. Here, for example, blank tolerances can be compensated.

In particular, changes in the sewing behavior due to a change in the angle of the sewing direction between the warp and weft direction of the fabric can be compensated. Such compensation can for example be made steplessly adapted when sewing bent seams.

As an alternative to triggering the feed change via external sensors, this can also be done depending on internal parameters, for example the number of sewn stitches or the sewn seam length.

Claims (8)

1. Sewing machine (1) comprising

   - a feed unit (14) for intermittent feeding of fabric, comprising

   -- at least one upper feeder (15) providing an intermittent frictional feed contact with an upper side of the fabric;

   -- at least one lower feeder (16, 17) providing an intermittent frictional feed contact with an underside of the fabric;

   - a mechanical upper feed adjustment device (34) for adjusting a feed length of the at least one upper feeder (15);

   - a mechanical lower feed adjustment device (30, 31) for adjusting a feed length of the at least one lower feeder (16, 17);

   - an upper feed adjustment drive (35) for adjusting the upper feed adjustment device (34);

   - a lower feed adjustment drive (18, 32) for adjusting the lower feed adjustment device (30, 31);

   a control device (38) which is in signal connection with the lower feed adjustment drive (18, 32) and the upper feed adjustment drive (35) and has a storage device (39) in which data are stored regarding sewing sequences to be executed as well as adjustment data which are assigned to these sewing sequence data for independently actuating the adjustment drives (18, 32, 35) when the sewing sequence is executed,

   - the adjustment devices (30, 31, 34) are guided slider mechanisms having at least one guided-slider adjustment body (24) that is displaceable along an adjustment direction (18, 32, 35) of the respective adjustment drive,

   - at least one of the adjustment devices (30, 31, 34) has a cam disk (19) that is drivable for rotation by the assigned adjustment drive (18, 32, 35), the cam disk (19) having a circumferential area (20) the radius of which varies over circumferential portions, wherein an adjustment body (21) interacts with sections of the circumferential area (20) for adjusting the feed length, the adjustment body (21) being mechanically coupled to the assigned feeder (15 to 17).
2. Sewing machine according to claim 1, characterized in that the feed unit (14) additionally comprises:

   - at least an additional lower feeder (17, 16) providing an intermittent frictional feed contact with the underside of the fabric;

   - wherein the two lower feeders (16, 17) have contact portions along a sewing direction (13), the contact portions being disposed at a distance from one another for providing a feed contact with the underside of the fabric;

   - an additional mechanical lower feed adjustment device (31, 30) for adjusting a feed length of the additional lower feeder (17, 16);

   - an additional lower feed adjustment drive (35, 32) for adjusting the additional lower feed adjustment device (31, 30);

   - wherein the control device (38) is also in signal connection with the additional lower feed adjustment device (31, 30); and

   - wherein additional adjustment data are stored in the storage device (39), these additional adjustment data being assigned to the data regarding sewing sequences to be executed, for actuating the additional lower feed adjustment drive (35, 32) when the sewing sequence is executed.
3. Sewing machine according to one of claims 1 to 2, characterized by a stepper motor (18, 32, 35) as adjustment drive.
4. Sewing machine according to one of claims 1 to 3, characterized in that the at least one adjustment drive (18, 32, 35) is housed in a housing of the sewing machine (1).
5. Sewing machine according to one of claims 1 to 4, characterized in that the control device (38) is connected to a thread tensioning device.
6. Method of operation of a sewing machine according to one of claims 1 to 5 comprising the following steps:

   - setting a first feed value for moving the fabric by means of the at least one upper feeder (15) and the at least one lower feeder (16, 17);

   - sewing the fabric with the first feed value;

   - setting a second feed value for moving the fabric by means of the at least one upper feeder (15) and the at least one lower feeder (16, 17), the second feed value being different from the first feed value;

   - sewing the fabric with the second feed value.
7. Method of operation of a sewing machine according to one of claims 1 to 5 comprising the following steps:

   - setting a first gathering feed value for moving the fabric by means of the at least one upper feeder (15) and the at least one lower feeder (16, 17), wherein the first gathering feed value is the ratio between the feed lengths of the upper feeder (15) and the lower feeder (16, 17);

   - sewing the fabric with the first gathering feed value;

   - setting a second gathering feed value for moving the fabric by means of the at least one upper feeder (15) and the at least one lower feeder (16, 17), the second gathering feed value being different from the first gathering feed value;

   - sewing the fabric with the second gathering feed value.
8. Method of operation of a sewing machine according to claim 2 or according to one of claims 3 to 5 when at least dependent from claim 2, comprising the following steps:

   - setting a first ruffling feed value for moving the fabric by means of the two lower feeders (16, 17), wherein the ruffling feed value is the ratio between the feed lengths of the one lower feeder (16) and the other lower feeder (17);

   - sewing the fabric with the first ruffling feed value;

   - setting a second ruffling feed value for moving the fabric by means of the two lower feeders (16, 17), the second ruffling feed value being different from the first ruffling feed value;

   - sewing the fabric with the second ruffling feed value.

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