EP3241937A1 - Apparatus and method for manually exchanging a transporter - Google Patents

Abstract

A sewing machine comprises a device for manually changing a feed dog (10), comprising the feed dog (10) and a feed dog holder (30), wherein the feed dog holder (30) is arranged in a free arm (103) belonging to the sewing machine, the feed dog (10) 10) in a recess (31, 81) of the feed dog holder (30) is receivable. The conveyor (10) located in the recess (31, 81) has a support surface (15) which can be arranged parallel to the surface of a fabric support which can contain a taphole plate (113) or can be formed as a taphole plate (113). wherein the Nähgutauflage and / or the tap hole plate (113) at least partially from the surface of the free arm (103) can be formed, wherein the support surface (15) in an opening (140) of the tap hole plate (113) can be accommodated, wherein the feed dog ( 10) can be fastened in the recess by means of a fastening element (40, 82, 83) or an adjusting element (50), so that the bearing surface (15) can be aligned essentially parallel to the surface of the sewing material pad or stitch hole plate (113). The fastening element (40, 82, 83) or adjusting element (50) is releasably held in the feed dog holder (30).

Description

The invention relates to a device and method for manually changing a feed dog for a sewing machine according to the preamble of patent claim 1.

Sewing machines each comprise a stitch forming device for creating seams or embroidery patterns in a textile sheet-like article, also referred to below as sewing material. The sewing machine has a machine head and a free arm. The machine head is located at the end of an upper arm. At the other end of the upper arm joins a stand element. Below the upper arm and extending substantially parallel to the upper arm, a so-called free arm is arranged. The free arm is connected at one end to the upright element. The free arm serves as a support for the sewing material. The machine head includes a needle which is moved up and down and periodically comes into contact with the fabric. There is a thread in the needle. The needle pierces the fabric. Hereby, the thread is connected to a lower thread located below the material, whereby a seam or a pattern is created. The needle is detachably connected to a needle holder disposed at a lower end of a needle bar. The needle bar is moved up and down by a needle bar drive. The machine head further includes a presser foot rod having a conical or tapered lower end for coupling and attachment of various presser feet. Depending on the type of sewing to be performed different presser feet are used. At the beginning of the work, the presser foot is lowered with the presser foot so that the sole of the presser foot rests on the fabric. In this position, the fabric is located between the feed dog and the sole of the presser foot so that the location where a needle stitch is to be performed is precisely defined. By means of the conveyor, the fabric can be moved into the correct position prior to the execution of the next stitch, so that a continuous seam or a continuous pattern can be produced in this way. The feed dog thus serves to ensure the feed of the material. Of course, the fabric can also be moved manually in the plane containing the fabric. This operating mode is used, for example, for stuffing or quilting. A sewing machine can therefore be operated on different operating modes. Therefore, various types of sewing machines are offered today, for example, by the width of the used Transporters differ. However, when purchasing the sewing machine, the buyer determines the width of the carrier during the purchase decision.

For switching between different operating modes of the sewing machine, however, it may be useful for the user to work with a conveyor of different widths. Therefore, there is a need for a device by which the user is able to use different conveyors. Such a device is used to change the transport width or the feed dog shape in order to expand the range of use for a sewing machine. This sewing machine is intended especially for the end user, ie for use in private households.

Devices for adjusting the transport height are eg from the CN 10 48 78 522 A known, which shows a vertically extending conveyor, which is raised or lowered by means of an attached to the shaft located in the free arm eccentric periodically according to the rotational speed of the shaft. A retaining clip for height adjustment of a transporter is from the CN 20 41 74 392 U known. Devices for adjusting the transport feed are eg off CN 10 43 42 853 , from the DE 10 2007 026 651 A1 for an upper feed dog and two different lower feed adjusting drives for a first and second lower feed dog. A transporter drive with adjustable feed direction is from the DE 3 629 514 A1 known. However, the prior art does not disclose a device or a method for changing the entire transport or for setting / changing the transport width or the shape. It is off US 1 992 781 A Also known to adjust the angle of inclination of the transporter relative to the fabric support, but the transport width remains unchanged.

Nowadays, the user must already decide on the purchase of a sewing machine with a corresponding transporter, that is, the transport width and shape of the carrier are determined with the purchase decision forever. This decision is usually made by the user due to the more frequent application or the basic needs to be met. Depending on whether the sewing machine is more needed for classic sewing applications or for creative sewing, the user chooses a machine with a wider or narrower feed dog. Accordingly, the basic setting is already made by the purchase decision, which limits the user in the variety of applications. Therefore, in some applications, the sewing machine is out of the optimal settings related to fabric transport.

Unlike industrial sewing machines, which usually have a very small application range or allow a small variety of applications and are therefore bought and manufactured especially for a few applications, the household sewing machine, regardless of the purchase decision made (for example, 5.5 mm or 9.0 mm transport width), always achieve at least satisfactory results in all fields of application. For this reason, the mechanical setup, the unchanging basic setting of the sewing machine, must always be seen as a certain compromise, which means that the material transport is maximally optimized for a rough field of application, for example creative sewing or classic sewing applications.

Therefore, there is a need for a device for presetting the sewing machine for a particular application, for example when using a special fabric or sewing technique that does not have the disadvantages of the prior art.

The problem to be solved by the invention is that the sewing machine or the fabric transport can be adjusted individually to the respective sewing application at any time after purchase. Another object of the present invention is to provide an apparatus and method for presetting a sewing machine which enables pre-setting before the user uses the sewing machine for a special sewing process, so the sewing machine is optimized for this particular sewing process.

Another object of the invention is to provide the user with the ability to operate the sewing machine in different modes, whereby the user can switch from one mode to another by presetting the sewing machine and the sewing machine is optimally pre-set for the particular mode of operation.

These objects are achieved by a sewing machine comprising a device for manually changing a transporter according to claim 1. Particular embodiments of the invention are the subject of the dependent claims.

A sewing machine comprises a device for manually changing a conveyor, comprising the feed dog and a feed dog holder. The feed dog holder is arranged in a free arm belonging to the sewing machine, wherein the feed dog is receivable in a recess of the feed dog holder. This recess can also be arranged according to an embodiment in an arranged in the feed dog insertion element. The conveyor located in the recess has a support surface which is parallel to the surface of a Nähgutauflage may be arranged, wherein the Nähgutauflage may contain a tap hole plate or may be formed as a tap hole plate. The Nähgutauflage and / or the stitch hole plate may be at least partially formed by the surface of the free arm. The feed dog has a base surface, which is arranged opposite the bearing surface, wherein the base surface rests on a base surface of the recess in the assembled state at least partially. For example, the Nähgutauflage include a tap hole plate. In particular, the surface of the free arm may include a tap hole plate or be formed as a tap hole plate. The support surface is received in particular an opening of the tap hole plate. The feed dog can be fastened in the recess by means of a fastening element or an adjusting element, so that the bearing surface can be aligned essentially parallel to the surface of the sewing material support or needle hole plate. The fastener or the adjustment is releasably held in the feed dog holder.

The opening can have a greater length than the feed dog or the web of the feed dog guided through the opening, so that the position of the feed dog with respect to the opening can be varied. This means that the position of the feed dog in the feed direction of the sewing material can be changed. Alternatively or in addition to this, a transporter having a larger or smaller longitudinal dimension can be used. Thus, the available for the transport of the sewing material transfer area can be changed. This allows the replacement and replacement of transporters with different longitudinal dimensions.

According to one embodiment, the recess may have at least one side edge, which limits the base area at its edge, wherein the feed dog is at least partially received by the side edge of the recess.

According to one embodiment, the opening may have a greater width than the feed dog so that the width of the feed dog is variable. This allows the replacement and replacement of transporters with different width dimensions. Of course, the preceding embodiments can be combined in such a way that both transporters of different length dimensions and transporters of different width dimensions or transporters with different length dimensions and width dimensions can be used. Depending on the selected transporter and the matching tap hole plate is used.

According to one embodiment, the feed dog can be adjustable and / or lockable by the adjusting element in its position relative to the recess. In particular, the adjustment may comprise an eccentric, wherein the eccentric is guided on a pin or formed as part of a pin which is held in a recess of the conveyor and is held in a threaded bore in the feed dog holder. According to one embodiment, the adjusting element may comprise a locking element.

According to one embodiment, the fastening element comprises a screw. In particular, the fastener can not protrude beyond the surface of the conveyor. That is, the height of the fastener corresponds maximally to the bearing surface formed by the surface of the conveyor. According to an alternative embodiment, the fastening element comprises a threaded bolt and / or a nut. According to a further embodiment, the fastening element comprises a guide rail. According to a further embodiment, the fastening element comprises a bolt.

According to one embodiment, the fastening element is at least partially held in the recess of the feed dog holder and / or in an insertion element. It Different insertion elements can also be used. For example, the depth of the recess of the insert element can be varied so that transporters of different thicknesses can be used. It is also possible to use different insertion elements in combination with transporters of different length dimensions and / or width dimensions and / or thicknesses. The thickness is understood to be the dimension of the conveyor in the installed state in the Z direction. The term "length dimension" is understood to mean the maximum dimension of the transportor or the support surface, which can be formed at least by the webs, in the feed direction of the workpiece, ie in the Y direction. The width dimension is understood to be the maximum dimension of the transporter in the X direction.

According to one embodiment, the feed dog can be positioned in the recess by means of a fixing element or a locking element. The fixing element contains, for example, a magnet or a ferromagnetic region. The locking element can be rotatably arranged in the feed dog holder.

The different transporters can be exchanged by the user himself in order to be able to select the optimal mechanical setup for the application or the suitable transport width and shape.

Due to the high demands placed on the material transport or the orientation of the conveyor, in the case of today's sewing machines, each transport user must be individually aligned during assembly from the factory in order to be able to ensure optimum material transport. In the orientation of the conveyor, it is important that the flanks of the conveyor are parallel to the recess in the needle plate or perpendicular to the free arm of the sewing machine to ensure a uniform mass transfer without delay. As for the alignment of the transport experience and craftsmanship is required, which is usually not available for an average user, also a device for aligning the individual transporters must be provided in addition to the pure changing device.

According to one embodiment of the invention, the screw connection is described independently of the device for aligning the conveyors. Here, in the simplest embodiment, the various conveyors are fastened by two screws on the feed dog holder. A disadvantage of this relatively simple embodiment is that the screws fall when changing the individual conveyors in the open sewing machine or otherwise can be lost. Therefore, a further embodiment provides Fuse element before. This securing element is used in particular to ensure that the two screws on the conveyor, so that they are not lost or can fall into the machine. If a screw would fall into the sewing machine or the free arm during the feed dog change, this could lead to considerable damage when starting the machine, for example in the region of the stitch-forming means, for example the thread cutter.

A securing element is in this case formed in the simplest embodiment as an element from the group of chains or cords and ensures that the screws can not be lost. This embodiment has the disadvantage that the chain or cord rotates when fastening the screw, and thus wound around the screw, which can lead to complications in the attachment. The screw lock can also be designed as a co-rotating fuse by being attached via a plastic part with a snap connection to the screw head or is rotatably attached to the upper end of the screw shaft.

Since the feed dog holder is a relatively fast moving part that can be driven at speeds of up to 1,500 rpm and accordingly execute 1,500 sequences of movements per minute can, this must be relatively easily formed, which is why this is usually made of aluminum. This results in the screw-type embodiment described above, in addition, the problem that the feed dog holder can be damaged relatively quickly when mounting the conveyor, by a faulty installation. This damage occurs, for example, when the steel screw is incorrectly screwed, for example by tilting, into the less solid aluminum, which damages the thread in the feed dog holder. This means that the feed dog can not be properly screwed. As a result, the machine may fail or maintenance may be required.

In order to overcome the disadvantages of the embodiment described above, a further embodiment provides that two threaded bolts are screwed into the feed dog holder during assembly and secured permanently with a securing element which contains, for example, a securing element from the group of Loctite screw locks or Tuflok screws or is fixed. The individual transporters are when changing, not, as described above, fastened by a screw on the feed dog holder, but screwed by a nut at the upper end of a threaded bolt. By the Material pairing as well as a guidance of the nut relative to the bolt, the risk of a faulty incorrect operation can be significantly reduced. Similar to the previous embodiment, the nuts are also secured to the transfer door to prevent them from being lost or falling into the machine. This backup is realized in the preferred embodiment by a sheet attached to the transport door.

In order to ensure that the transport gate is aligned as described when changing, it is aligned on the one hand via a fit in the transport door and the associated fastening element. By this orientation, the freedom of movement in Z and X direction is prevented or at least limited. In this case, the X direction is defined as the longitudinal direction of the free arm, the Y direction corresponds to the transverse direction of the free arm or the feed direction of the sewing material. The Z-direction is normal to the support surface, ie in the direction of the lifting or lowering movement of the sewing needle, directed.
The restriction of the freedom of movement in the Y direction or the final orientation of the conveyor takes place by the interaction of the fastening element with an eccentric device, which is in the optimal case in the vicinity of the second fastening means. The above-described orientation of the carrier takes place here during assembly ex works for each machine via the eccentric device.
Due to the selected manufacturing tolerances ensures that the surface on which the eccentric aligns the feed dog, has a sufficiently accurate shape and location, so that the various conveyors are aligned exactly enough on the eccentric, so that the requirements for mass transfer or the positioning of the transport be ensured.

If in the production no sufficiently accurate shape and position tolerances of the transporter can be achieved, there is a mating of the different transporters to each other. This pairing is done by a common processing step. This processing step provides that the surface on which the eccentric device aligns the feed dog is finally machined together in a tool.

Regardless of the final processing step, the alignment is preferably carried out by a lateral recess or on the rear side of the conveyor. The advantage of the lateral recess is that the transporter aligns itself when changing. When aligning to the rear of the transporter, the user must either make sure that this also really rests on the eccentric device or pulled or held by such as a magnet to this. In addition, a fixation element, for example a magnet, is integrated into the feed dog holder as an assembly aid for the user, by means of which the feed dog is provisionally held in the cutout. This ensures that the transporter can be mounted with both hands and not one is occupied with the holding of the transporter.

According to one embodiment, the attachment and the orientation are implemented separately from each other, by also integrating the dowel pin and the eccentric separately from the fasteners in the feed dog holder. For this purpose, the fit is positioned via a bolt integrated in the feed dog holder and a further hole provided in the feed dog. It would also be conceivable that the eccentric is not positioned on an outer surface or recess of the conveyor, but also via a separate hole in the feed dog holder.

As in the previous embodiment, the freedom of movement in the Z and X direction is fixed or restricted in this case via a fit in the feed dog and the associated fastening element. The further alignment of the transporter takes place in this Embodiment by a template or an attached alignment web. Alignment is accomplished by inserting the alignment bar from the top, between the one edge of the feed dog and the edge of the needle plate, before final tightening. The tap hole plate contains a breakthrough in which the feed dog moves while sewing. To ensure that the edge of the conveyor abuts the alignment web of the template, on the opposite side either a recess, a slider device with a driver part or the like is provided so that the feed dog can be manually pressed in the direction of the alignment web. According to an alternative embodiment, in each case a magnet may be placed in the middle or at the beginning and at the end of the alignment web, so as to ensure that the feed dog rests against the alignment web. To ensure that the feed dog rests against the alignment bar, it can be fixed as described above. Due to the limited space available, a special needle plate could be used, so that the space between the edge of the conveyor and the edge of the needle plate is used.

In a further embodiment, the feed dog is not aligned with the tap hole plate but at the gap between the feed dog and the feed dog holder.

In another embodiment, the feed dog is not aligned with an alignment web of a template inserted from above, but with an edge of a special taphole plate. Here, similar to the alignment web, the feed dog is pressed against an edge of the stitch hole plate by manual pressing or by a magnetic device while being fastened to the feed dog holder via the fastening elements.

According to a variant, the feed dog may be placed in a taphole plate in which it is e.g. held by at least one magnet and positioned over depressions. This tap hole plate is then placed on and the feed dog can be attached through holes or holes in the tap hole plate. In this case, the stitch hole plate used for sewing can be readjusted via an eccentric device to ensure that it sits optimally or does not drag.

According to a further embodiment, a presser foot is used for aligning, which, for example, at a Flank of the carrier abuts or engages in toothing of the support surface of the conveyor to align the respective feed dog. According to a further embodiment, the fixing element, so for example, the template or the alignment, rest for aligning the carrier on the edge and / or engage on the teeth and / or attached to the needle bar.

According to one embodiment, an alignment of the conveyor takes place via a zigzag stitch of the sewing machine. For this purpose, the transporter is first provisionally fixed, for example, slightly screwed, and positioned over the fit on the feed dog holder in the X direction. Positioning in the Y direction takes place by the sewing needle aligning the flanks of the feed dog via the corresponding zigzag stitch. After this is done, it can be tightened. For alignment detected in analogy to the sewing a hook on a rotating or oscillating gripper formed during the return stroke of the sewing needle loop and guides it around the gripper with the lower thread spool mounted therein and wraps around the lower thread. Then the thread lifter pulls the upper thread upwards and the needle also moves upwards until the knot lies at the desired location at the bottom or on the sewing material. Then the sewing needle is moved with the needle bar by an amount ΔY in the Y direction, to make a stitch that is offset to the first stitch in the X and Y directions, creating a serrated shape. The feed dog pushes the fabric between the punctures of the sewing needle. The distance of the first stitch from the second stitch measured in the Y direction, ie the stitch width of the zigzag stitch, corresponds to the width of the distance of the first arm of the conveyor from the second arm. Thus, the feed dog can be precisely aligned by performing a zigzag stitch.

The described sewing operation is only for replacing and aligning the feed dog when creating another type of seam. For any kind of seam formation, the stitch formation remains unchanged, which is why the technique of stitch formation does not and need not be described per se.

In the present embodiment, the respective conveyors are not attached via a conventional screw on the feed dog holder, but guided in a guide and locked. Here, the guide is not limited to the guide systems described below. First, the linear guide is described independently of the attachment of the respective transporters. The linear guides described here can be both vertically and horizontally to the fabric transport direction, that is, in the Z direction or Y direction.

In a first embodiment, the feed dog is guided in an adjustable linear guide. Here, the feed dog is designed as a carriage and the feed dog holder as a lower or guide member and set with an adjustment between the carriage and guide member. The individual transporters can be adjusted to the respective machine during assembly ex works, to ensure that they meet the requirements of mass transfer. The guides may include an element from the group of dovetail guides, encompassing linear guides.

In a further embodiment, the feed dog is guided by two guides in the feed dog holder. Thus, the system is designed as such statically not overdetermined, a guide is designed as a fixed bearing and a guide as a floating bearing.

The locking of the transporter can also be carried out screwed over at least one screw, both independently of the div. Formations of the guide elements as described above. Since the goal of the guided transporter replacement device was a user-friendly embodiment, the screw-type variant is not preferred.

A snap device can lock this in an end position during insertion of the feed dog. The snap mechanism is described here e.g. locked by a corresponding laterally arranged on the feed dog recess and a corresponding snapper in the feed dog holder or the guide member. To change the snap mechanism can be unlocked.

According to a variant of the feed dog can be locked by means of a tiltable locking mechanism. In this case, the relatively small force required, which is needed to hold the transporter, be applied by a spring. The locking occurs e.g. by a locking element, which may contain an element from the group of bolts, plates, which is guided or held by the feed dog and the feed dog holder or the guide part. In this case, the locking element can be performed both vertically and horizontally.

According to one embodiment, the locking of the conveyor by a quick-release mechanism, which may be configured similar to a

Quick release mechanism for bicycles. When closing the transport door in the Z direction, the tensioner fixes or tensions it.

The latches listed above can be both manually, as well as automatically, for example, electrically driven, operated by the user or apply the holding force and / or hold. Furthermore, both the tiltable locking mechanism and the quick release mechanism can serve as substitution for the screw connection of one of the preceding embodiments, insofar as the locking mechanism is made in two parts, a first part is designed as a fit, ie without play, and a second part is executed with a certain play, to ensure alignment via the eccentric device.

In this embodiment, the feed dog is also formed in several parts. The shape or the width are hereby changed by, can be attached to an existing part of the carrier differently executed or shaped extensions of the conveyor. The extension of the existing transporter can be attached either by a click connection on the underside of the existing part, or by a Sicherungssplint or a screw connection.

The greatest advantage of the prior art is that by a change device of the conveyor by presetting the sewing machine for the particular application is optimal or can be adjusted in this regard. Thus, this means that the configuration of the sewing machine is changed, giving the user an increased number of degrees of freedom for setting the sewing machine. For this reason, the sewing machine is no longer limited to the rough range of application, that is, for example, set either a classic sewing application or creative sewing, but especially to the desired application. Furthermore, the configuration can be optimized not only for the application but also for the material to be sewn.

Fig. 1

eine perspektivische Darstellung eines ersten erfindungsgemässen Ausführungsbeispiels in Explosionsdarstellung,

Fig. 2

eine Ansicht der Schraubensicherung gemäss Fig. 1,

Fig. 3

eine zweite Ansicht der Schraubensicherung gemäss Fig. 1 oder Fig. 2,

Fig. 4

eine perspektivische Darstellung eines zweiten erfindungsgemässen Ausführungsbeispiels in Explosionsdarstellung,

Fig. 5

ein Detail einer Variante eines Transporteurs zum Einsatz für das Ausführungsbeispiel gemäss Fig. 4,

Fig. 6

einen Schnitt durch das Befestigungselement des in Fig. 4 gezeigten Ausführungsbeispiels im eingebauten Zustand,

Fig. 7

einen Schnitt durch das Befestigungselement des in Fig. 4 gezeigten Ausführungsbeispiels im eingebauten Zustand,

Fig. 8

eine perspektivische Darstellung des zweiten erfindungsgemässen Ausführungsbeispiels in Explosionsdarstellung mit einer Variante für das Halteelement,

Fig. 9

eine perspektivische Darstellung des zweiten erfindungsgemässen Ausführungsbeispiels in Explosionsdarstellung mit einer weiteren Variante für das Halteelement,

Fig. 10

eine Ansicht eines dritten Ausführungsbeispiels von oben,

Fig. 11

einen Schnitt durch den Transporteur und die zugehörige Linearführung,

Fig. 12

eine Ansicht einer Variante der Linearführung in der Y-Z Ebene,

Fig. 13

eine Seitenansicht einer Variante der Linearführung in X-Z-Ebene,

Fig. 14

eine perspektivische Ansicht der Schiene gemäss Fig. 12,

Fig. 15

eine schematische Darstellung einer Nähmaschine,

Fig. 16

eine perspektivische Darstellung eines vierten erfindungsgemässen Ausführungsbeispiels in Explosionsdarstellung,

Fig. 17

eine weitere perspektivische Darstellung eines vierten erfindungsgemässen Ausführungsbeispiels in Explosionsdarstellung gemäss Fig. 16,

Fig. 18

eine Ansicht auf den Transporteur in Fig. 16 im eingebauten Zustand,

Fig. 19

einen Schnitt durch den Transporteur gemäss Fig. 16 im eingebauten Zustand,

Fig. 20

eine perspektivische Darstellung eines fünften erfindungsgemässen Ausführungsbeispiels in Explosionsdarstellung,

Fig. 21

eine Ansicht des fünften Ausführungsbeispiels von oben.

Based on illustrated embodiments, the invention will be explained in more detail. Show it

Fig. 1

a perspective view of a first embodiment according to the invention in exploded view,

Fig. 2

a view of the screw lock according Fig. 1 .

Fig. 3

a second view of the screw lock according Fig. 1 or Fig. 2 .

Fig. 4

a perspective view of a second embodiment according to the invention in an exploded view,

Fig. 5

a detail of a variant of a conveyor for use in the embodiment according to Fig. 4 .

Fig. 6

a section through the fastener of in Fig. 4 shown embodiment in the installed state,

Fig. 7

a section through the fastener of in Fig. 4 shown embodiment in the installed state,

Fig. 8

a perspective view of the second embodiment according to the invention in an exploded view with a variant of the retaining element,

Fig. 9

a perspective view of the second embodiment according to the invention in an exploded view with a further variant of the holding element,

Fig. 10

a view of a third embodiment from above,

Fig. 11

a section through the feed dog and the associated linear guide,

Fig. 12

a view of a variant of the linear guide in the YZ plane,

Fig. 13

a side view of a variant of the linear guide in XZ plane,

Fig. 14

a perspective view of the rail according to Fig. 12 .

Fig. 15

a schematic representation of a sewing machine,

Fig. 16

a perspective view of a fourth embodiment according to the invention in an exploded view,

Fig. 17

a further perspective view of a fourth embodiment according to the invention in an exploded view according to Fig. 16 .

Fig. 18

a view of the transporter in Fig. 16 when installed,

Fig. 19

a section through the feed according to Fig. 16 when installed,

Fig. 20

a perspective view of a fifth embodiment according to the invention in an exploded view,

Fig. 21

a view of the fifth embodiment from above.

A device for manually changing a transport 10 for a sewing machine according to Fig. 1 includes the feed dog 10 and a feed dog holder 30. For the sake of clarity, the figures have been omitted from the description of the details of the sewing machine, since they are well known in the prior art, see for example CH707972 A1 , The feed dog 10 can be received in a recess 31 of the feed dog holder 30. The carrier holder 30 is arranged in a free arm 103 of the sewing machine 101, which is in Fig. 15 is shown. The feed dog 10 can be fastened in the recess 31 by means of a fastening element 40, wherein the fastening element 40 is held releasably in the feed dog holder 30. The fastener 40 may include, for example, a screw 41.

According to the embodiment in Fig. 1 For example, various transporters 10 can be attached to the feed dog holder 30 by two screws 41.

In Fig. 1 is also an adjustment 50 shown, through which the feed dog 10 is adjustable in position relative to the recess 31. The adjustment 50 according to Fig. 1 is formed as a pin having a head end 51 and a neck 52. The head end 51 has a larger diameter than the neck 52. The neck 52 may have an external thread. The neck 52 can be held at least partially in a bore 33 which is mounted in the recess 31. The bore 33 may be formed as a threaded bore. On the neck 52, an eccentric disc 55 can be arranged. The eccentric disc 55 is received in a holder 11 of the carrier 10 when the feed dog 10 is inserted into the recess 31.

Instead of a separate eccentric disc 55 and the head end 51 could be formed as an eccentric, which is not shown in the drawings. Depending on the position of Eccentric 55, therefore, the position of the carrier 10 in the recess 31 can be fixed. The head end 51 may comprise a receiving element for an actuating key. According to a further embodiment, the head end 51 may have a rough profile or a grooving, which makes it possible to manually rotate the head end 51 to bring the eccentric disc 55 in the desired position, whereby a fine adjustment of the conveyor 10 can take place. The feed dog 10 can thus be aligned in accordance with the contour located in the stitch hole plate 113 of the sewing machine 101. Such a tap hole plate 113 is for example in Fig. 9 shown.

If two fasteners 40 are used, one of the fasteners 40 without play, so with fit, be included in the bore 12 of the carrier 10 and the other fastener 40 without fit, so be included with game, in the associated bore 13 of the conveyor 10 ,

A fixing element 86, which may be formed, for example, as a magnetic element, in particular as a magnetic pin, may be used to fix the feed dog 10 in the correct position before the locking of the feed dog 10 by the fixing element or elements 40 takes place.

Fig. 2 and Fig. 3 show, for example, the screw 41 of Fig. 1 and a screw lock 42. The second screw the Fig. 1 can have a similar screw lock. The screw lock 42 is formed according to this embodiment as a thin-walled cylinder 43 with a flat top surface 44. The top surface 44 has a central opening 45, through which the screw head 46 projects. The screw head 46 has a receptacle 47 for an actuating key. Through the opening 45 in the top surface 44 of the thin-walled cylinder 43 ensures that the user can loosen or tighten the screw 41 at any time.

The thin-walled cylinder 43 has a tab 48 at the end, which is opposite to the top surface 44. The tab 48 engages in the assembled state, the screw head 46th

As in Fig. 1 is shown, the screw head 46 is optionally together with the screw lock 42 in a paragraph of a corresponding hole in the feed dog. The screw lock is in Fig. 1 not shown. The thin-walled cylinder has a bore or hole through which a rope is guided, which is also secured in the feed dog holder or in the feed dog so that the screw can not fall into the sewing machine.

The securing element is in this case designed so that the rope can rotate and does not wrap around the screw.

The screws 41 have a screw neck 49. In the assembled state, the screw neck 49 projects through the bore in the feed dog 10 and is held in a threaded bore 32 arranged in the recess 31. The screw neck 49 has for this purpose a not shown in the drawings external thread.

A device for manually changing a feed dog 10 for a sewing machine 101 according to Fig. 4 includes the feed dog 10 and a feed dog holder 30. The feed dog 10 is receivable in a recess 31 of the feed dog holder 30. The feed dog holder 30 is arranged in a free arm 103 of the sewing machine 101, which is shown in FIG Fig. 15 is shown. The feed dog 10 can be fastened in the recess 31 by means of a fastening element 40, wherein the fastening element 40 is held releasably in the feed dog holder 30. The fastener 40 may include a threaded bolt 60 and an associated nut 61.

According to the embodiment according to Fig. 4 For example, various transporters 10 may be secured to the feed dog holder 30 by two threaded bolts 60 and associated nuts 61.

In Fig. 4 is also an adjustment 50 shown, through which the feed dog 10 is adjustable in position relative to the recess 31. The adjustment 50 according to Fig. 4 is formed as an adjusting screw 65 having a screw head 66 and a screw neck 67. The screw head 66 has a larger diameter than the screw neck 67. The screw neck 67 may have an external thread 68. The screw neck 67 can be held at least partially in a threaded bore 34 which is mounted in a holder 35 in the feed dog holder 30. On the screw neck 67, an eccentric disc 69 can be arranged. The eccentric disc 69 is received in the holder 35 of the feed dog holder 30 when the feed dog 10 is inserted into the recess 31 and abuts the feed dog 10. Due to the position of the eccentric eccentric of the feed dog 10 can be finely adjusted in the recess 31.

Instead of a separate eccentric disc 69 and the screw head 66 could be formed as an eccentric, which is not shown in the drawings. Depending on the position of the eccentric disc 69, therefore, the position of the carrier 10 in the recess 31 can be fixed. The screw head 66 may comprise a receiving element for an actuating key. After another Embodiment, the screw head 66 may have a rough profile or a grooving, which makes it possible to rotate the screw head 66 manually to bring the eccentric 69 in the desired position, whereby the fine adjustment of the conveyor 10 can be done. The feed dog 10 can thus be aligned in accordance with the contour located in the stitch hole plate 113 of the sewing machine 101. Such a tap hole plate 113 is for example in Fig. 9 shown. In the FIG. 9 shown tap hole plate can not be used for sewing due to the large recess, but only serves as an alignment template.

If two fasteners 40 are used, one of the fasteners 40 without play, so with fit, be included in the bore 12 of the carrier 10 and the other fastener 40 without fit, so be included with game, in the associated bore 13 of the conveyor 10 , Alternatively or in addition thereto, two similar bores 12 may be provided in the feed dog and the first threaded bolt 60 with a fit and the second threaded bolt 62 may be designed without a fit. Alternatively or in addition to this, a holding plate 70 may be provided, which has two bores 71, the diameter of which substantially Outer diameter of the nuts corresponds. In particular, the holding plate may be formed as a holding plate.

Fig. 5 shows a conveyor 10 of another type, which on the in Fig. 4 shown feed dog holder 30 can be attached. The feed dog 10 has a first outer web 16 and a second outer web 17. The first outer web 16 and the second outer web 17 have a constant web width and have substantially the same length. Between the first outer web 16 and the second outer web 17, a central web 18 is arranged. The central web 18 has a larger web width than the first and second outer webs 16, 17. The central web 18 has a smaller length than the first and second outer webs 16, 17. The first and second outer webs 16, 17 and the central web 18 span the support surface 15, on which the fabric rests. The first and second outer webs 16, 17 and the central web 18 have a plurality of transverse grooves, which improve the adhesion of the material on the feed dog and allow the material to be grasped by the feed dog and moved in the feed direction.

The transporter in Fig. 4 is different from the one in Fig. 5 shown transporter to the effect that the central web 18 has a web width which is at least partially smaller than the web width of the first and second outer webs 16, 17 is. Furthermore, the first and second outer webs 16, 17 have a web width which is variable over the web length.

The first and second outer webs 16, 17 and the central web 18 may be connected to each other. Since the central web 18 is shorter than the first and second outer webs 16, 17, the first and second outer webs 16, 17 form two arm members defining a void space. This void space allows the sewing needle to be guided by the feed dog after the material has been pierced, so that the upper thread entrained with the sewing needle can form a loop which can be grasped beneath the feed dog by the hook of the gripper and can be connected to the lower thread.

Fig. 6 shows a section through the fastener 40 of the in Fig. 4 shown embodiment in the installed state. The fastening element 40 is shown in section, through which the feed dog 10 can be fastened in the recess 31. The fastening element 40 according to Fig. 6 is formed as a threaded bolt 62, which is held by means of a flange in the bore 32 of the feed dog holder 30 in a defined screw-in depth. Above the flange extends an area with a larger outer diameter than the outer diameter of which fits into the bore 32 Thread. The area with a larger outer diameter is designed to match the inner diameter of the bore 12 of the conveyor 10, so that the feed dog is mounted on fit. Above the fitting range, an external thread connects, which receives the internal thread of the nut 61. The nut rests on a shoulder located in the bore 12. The bore 12 is formed as a stepped bore. The lower part of the stepped bore has a smaller inner diameter than the upper part of the stepped bore. The upper part of the stepped bore thus receives the nut 61, which holds the conveyor captive on the feed dog holder 30. In addition, a holding element 70 may be provided, which is designed as a holding plate.

Fig. 7 shows a section through the fastener 40 of the in Fig. 4 shown embodiment in the installed state. The fastening element 40 is shown in section, through which the feed dog 10 can be fastened in the recess 31. The fastening element 40 according to Fig. 6 is formed as a threaded bolt 62, which is held by means of a flange in the bore 32 of the feed dog holder 30 in a defined screw-in depth. Above the flange extends an area with the same outer diameter as the outer diameter of the matching in the bore 32 thread. The area above the flange has a smaller outer diameter than the inner diameter of the bore 12 of the conveyor 10, so that the conveyor is mounted with clearance. Above the receiving area for the feed dog 10 includes an external thread which receives the internal thread of the nut 61. The nut rests on a shoulder located in the bore 12. The bore 12 is formed as a stepped bore. The lower part of the stepped bore has a smaller inner diameter than the upper part of the stepped bore. The upper part of the stepped bore thus receives the nut 61, which holds the conveyor captive on the feed dog holder 30. In addition, a holding element 70 may be provided, which is designed as a holding plate.

In Fig. 7 is also the adjustment member 50 shown in section, through which the feed dog 10 is adjustable in its position relative to the recess 31. The adjustment 50 according to Fig. 7 is formed as an adjusting screw 65 having a screw head 66 and a screw neck 67. The screw head 66 has a larger diameter than the screw neck 67. The screw neck 67 may have an external thread 68. The screw neck 67 can be held at least partially in a threaded bore 34 which is mounted in a holder 35 in the feed dog holder 30. On the screw neck 67 can be an eccentric 69th are arranged, which is formed in one piece with the adjusting screw 65 in this embodiment. The eccentric disc 69 is received in the holder 35 of the feed dog holder 30 when the feed dog 10 is inserted into the recess 31 and is located on the feed dog 10, that is, in particular on the rear wall of the carrier 10. Due to the position of the eccentric cam 69 of the Transporter 10 are finely adjusted in the recess 31.

Fig. 8 shows a perspective view of the second embodiment according to the invention in exploded view with a variant of the holding element. For those elements already related to Fig. 4 is described in the description Fig. 4 directed. They bear the same reference numerals as in Fig. 4 have been used. The adjusting element 50 is designed as a template 72, which is part of the holding element 70. The template is designed as a web element, which can compensate for the difference in the width of the conveyor. The template abuts the second outer web 18 of the conveyor 10. The template 72 is removed after aligning the Transportwerers or before Nähbeginn again and is only for alignment. The alignment is accomplished by positioning the back surface of the template 72 in a recess of the feed dog holder 30.

Thereafter, the feed dog or the outer web 18 is pressed against this side surface of the template and screwed over the two holes with the feed dog holder 30. After the feed dog is screwed on, the template 72 is removed and the appropriate taphole plate (not shown) is inserted.

Fig. 9 shows a perspective view of the second embodiment according to the invention in an exploded view, which shows a further variant of the retaining element 70, which is formed in this embodiment by the needle plate 113. The tap hole plate has a recess, which is adapted to the contour of the conveyor 10, so that the feed dog is positioned exactly in the tap hole plate 113. Again, the tap hole plate 113 serves only as a template for aligning. The feed dog 10 is easily screwed on. The tap hole plate 113 is inserted and positioned over the usual holder in the free arm. Thereafter, the feed dog 10 and the outer web 17 is pressed on one side and screwed tight. Thereafter, the tap hole plate 113 is replaced with a stitch hole plate for sewing.

Fig. 10 shows a view of a third embodiment from above, in which the feed dog 10 in the feed dog holder 30 by a fastener 40 is held, which is designed as a guide rail. The feed dog is held in position by a retaining element 70. The holding element 70 is formed by a snap element 73. The snap element 73 holds the conveyor captive on the guide rail. The snap element 73 is formed in this embodiment as a gripping arm, which is held by means of a spring element in its locking position.

Fig. 11 shows a section through the feed dog and the associated guide rail 37, which is designed as a linear guide. The guide rail 37 contains an adjusting element 50. The adjusting element 50 may be formed as an adjusting screw 56, which allows an adjustment of the conveyor in the X direction, ie in the transverse direction to the feed direction.

Therefore, according to this first embodiment of the fastener 40, the feed dog 10 is guided in a guide rail 37 which is formed as an adjustable linear guide. Here, the feed dog 10 is formed as a carriage and the feed dog holder 30 as a lower or guide member and adjusted with an adjustment member 50 between the carriage and guide member. The individual transporters 10 can so in the assembly from the factory, to the respective sewing machine 101 be adjusted to ensure that they meet the requirements of mass transfer. The guide rail 37 may include a member of the group of dovetail guides, encompassing linear guides.

Fig. 12 shows a view of a guide member 20 for a feed dog 10. The feed dog 10 includes the guide member 20 or may be mounted on the guide member 20. The guide element 20 has a base body, which contains a guide carriage, so that a linear guide is formed. The guide carriage includes a first clamping element 22, which allows a fixation of the conveyor 10 in the Z direction and a second clamping element 23, which allows a fixation of the conveyor 10 in the Y and Z directions.

In particular, two clamping elements may be provided, wherein one of the clamping elements allows the adjustment in the X direction and the other of the clamping elements, the adjustment in the X and Z directions. Thus comes the clamping element, which makes the adjustment in the X direction as a floating bearing in use and the clamping element, which makes the adjustment in the X and Z directions, as a fixed bearing for use. By the clamping element 22, 23 of the feed dog is not finally secured in the working position in the sense of held, but merely braced and held by a fuse element not shown final in the working position or secured.

The guide member 20 has a in the Fig. 12 Left side arranged arm member 24 and a right side arranged arm member 25. Each of the arm members 24, 25 carries a cross-sectionally c-shaped support member 21, in each of which a clamping element 22, 23 can be accommodated. According to an embodiment, not shown, the clamping element 22, 23 may be integrated in the base body 5 or in the guide carriage 7.

Fig. 13 shows a side view of the guide member 20 of the conveyor 10 in the XZ plane. In the present embodiment, the support member 21 includes a groove in which one of the clamping elements 22, 23 is received.
The illustrated tensioning element 23 is an elastic element which is prestressed in the carrier element 21 in the form of a groove in such a way that it has a curvature. This curvature is applied to the wall of the feed dog holder 30, not shown here, so that by the radius of curvature of the clamping element 23, the distance of the carrier 10 to the feed dog holder 30 can be fixed.

Fig. 14 shows a view of the embodiment according to Fig. 13 associated feed dog holder 30. The feed dog holder 30 has a c-shaped cross-section. In the present embodiment, each of the legs of the c is formed a groove in which a support member 21, as in FIG. 12 or FIG. 13 shown is recorded. Each of the clamping elements 22, 23 is an elastic element, which is biased in the recess such that it has a curvature. By this curvature, a sheet is formed, which abuts against the wall of the feed dog holder 30, so that the feed dog 1 can be fixed by the contact pressure of the clamping element 22, 23 in the feed dog holder 30.

Fig. 15 shows a view of a sewing machine 101. The sewing machine 101 has a machine head 107 with a sewing device. The machine head 107 is disposed at the end of an upper arm 105. At the other end of the upper arm 105, a stator element 102 connects.
Below the upper arm 105 and extending substantially parallel to the upper arm 105, a so-called free arm 103 is arranged. The free arm 103 is connected at one end to the upright 102. The free arm 103 serves as a support for the sewing material 115. The machine head 107 includes a needle 111, which is moved up and down and periodically comes into contact with the sewing material 115. In the sewing needle 111, an upper thread 120 is guided. The sewing needle 111 pierces the sewing material 115, and thereby the upper thread 120 is connected to a lower thread 116 located below the Nähguts 115, whereby a seam or a pattern is generated. The sewing needle 111 is detachably connected to a needle holder disposed at a lower end of a needle bar 109. The needle bar 109 is moved up and down by a needle bar drive. The needle bar 109 is thus movable up and down in the direction of the needle bar axis A for performing sewing stitches, which is symbolized by the double arrow A '. In order to carry out zig-zag stitches, the needle bar 109 is additionally mounted pivotably in the machine head 107 about a pivot axis B transversely to the sewing direction N or in the longitudinal direction of the upper arm 105, which can be symbolized by the double arrow B '. The machine head 107 further includes a presser foot bar having a conical or tapered bottom end for coupling and attachment of various presser feet. The presser foot bar is not shown in the present illustration. Depending on the type of sewing to be performed different presser feet are used. At the beginning of the work, the presser foot is lowered with the presser foot, so that the sole of the presser foot rests on the sewing material 115. In this position, the sewing material 115 is located on the needle plate 113 between the feed dog 10 and the sole of the presser foot, so that the place where a needle stick is to be performed, is precisely defined. By means of the Transporter 10, the fabric 115 may be moved to the correct position before execution of the next stitch, so that in this way a continuous seam or a continuous embroidery pattern can be generated. The feed dog 10 thus serves to ensure the feed of the material 115. Alternatively, the sewing material 115 may be clamped on an embroidery frame. The embroidery frame can be moved in a plane containing the sewing material 115 in the x or y direction, so that the next insertion point of the sewing material 115 comes to rest under the sewing needle 111. The embroidery frame can be moved by means of a control element, which can be part of the sewing machine or can be coupled to an external computer. Of course, the sewing material 115 can also be moved manually over the trained by the tap hole plate and the adjoining surface of the free arm 103 support level. This operating mode is used, for example, for stuffing or quilting.

The taphole plate 113 includes a slot 114 through which the lower portion of the sewing needle 111 can be guided into the front portion of the forearm 103 when sewing after piercing the sewing material 115 on the taphole plate 113. That is, the lower portion of the sewing needle protrudes temporarily into the interior of the free arm 103 and is therefore below the tap hole plate 113. In this position can the lower thread 116 are covered by the sewing needle 111 and are linked to the upper thread 120 guided through the needle eye 129 of the sewing needle 111 such that a seam can be formed on the sewing material 115.

Fig. 16 shows a perspective view of a fourth embodiment according to the invention in an exploded view. The device for manually changing a conveyor 10 for a sewing machine according to Fig. 16 includes the feed dog 10 and a feed dog holder 30. The feed dog 10 is receivable in a recess 31 of the feed dog holder 30. The feed dog holder 30 is arranged in a free arm 103 of the sewing machine 101, which is shown in FIG Fig. 15 is shown. The feed dog 10 can be fastened in a recess 81 of an insertion element 80 by means of a fastening element 40, wherein the fastening element 40 can be detachably held in the insertion element 80. The

Fastener 40 may be formed, for example, as a bolt. According to the embodiment in Fig. 16 For example, various transporters 10 may be secured by two fasteners 40 in the insertion member 80. The insertion element 80 is received in the feed dog holder 30. In particular, the insertion element 80 is received in a recess 31 of the feed dog holder 30. The insertion element is 80 by means of one or a plurality of fasteners 82, 83 held in the feed dog holder 30.

In Fig. 16 an adjusting element 50 is also shown, by means of which the transporter 10 is adjustable in its position relative to the recess 31 and / or the insertion element 80. The adjustment 50 according to Fig. 16 is formed as a pin having a head end 51 and a neck 52. The head end 51 has a larger diameter than the neck 52. The neck 52 may have an external thread. The neck 52 may be held at least partially in a bore 33 which is mounted in the recess 31 or the recess 81. The bore 33 may be formed as a threaded bore. The adjustment member 50 may include a locking member 53. The locking element 53 serves the locking with respect to in the Fig. 16 not shown tap hole plate 113. The locking element 53 according to the present embodiment is formed as an L-shaped tab. The lower leg of the L is in the installed state in particular vertically aligned and protrudes into a corresponding recess of the tap hole plate 113, which in Fig. 19 is shown. The insert member 80 serves to align the feed dog. From the factory, the insert member 80 is easily screwed, the feed dog 10 used and by the adjustment member 50, for example, as a Locking element or retaining element is formed, only held. After the feed dog 10 has been aligned over the insert member 80, this is bolted to the feed dog holder 30.

The neck 52 may also be without fit, so with game, be formed or by a shaft lock, such as a Benz, (not shown) are held in the threaded bore 33, wherein instead of a threaded hole, a hole may be provided. The alignment does not take place via an eccentric. Both fasteners 40 are preferably designed as a fitting bolt, that is, play, executed.

As in Fig. 1 For example, the adjusting element 50 may comprise an eccentric disc, or the head end 51 may be formed as an eccentric, which, for example, in the embodiment according to FIG Fig. 20 is shown. The head end 51 may comprise a receiving element for an actuating key. According to a further embodiment, the head end 51 may have a rough profile or a grooving, which makes it possible to manually rotate the head end 51 to bring the locking element 53 in the desired position, whereby a determination of the conveyor 10 with respect to the needle plate 113th can be done. Also, the tab can serve as a handle or lever member to move the adjustment in the desired position.

The feed dog 10 can thus be aligned in accordance with the contour located in the stitch hole plate 113 of the sewing machine 101. Such a tap hole plate 113 is for example in Fig. 19 shown partially cut.

If two fasteners 40 are used, one of the fasteners 40 without play, so with fit, be included in the bore 12 of the carrier 10 and the other fastener 40 without fit, so be included with game, in the associated bore 13 of the conveyor 10 ,

A fixing element, which can be embodied, for example, as a magnetic element, in particular as a magnetic pin, can be used to fix the feed dog 10 and / or the insertion element 80 in the correct position before the locking of the feed dog 10 takes place through the fastening element or fasteners 40 The locking of the insertion element 80 by the fastening elements 82, 83 takes place.

Fig. 17 shows a further perspective view of a fourth embodiment according to the invention in an exploded view according to Fig. 16 , In Fig. 17 the insertion element 80 is shown, which has a first shoulder 84 and a second section 85. In paragraphs 84, 85, the holes 32 for the fasteners 82, 83 are provided. The side edges of the conveyor 10 abut against the inner edges of the shoulders 84, 45. In the recess 31 of the feed dog holder 30 may also each a paragraph 87, 88 may be arranged. The outer edges of the shoulders 84, 85 rest on the shoulders 87, 88 of the feed dog holder 30 when the insert element 80 is attached to the feed dog holder 30.

Fig. 18 shows a view of the feed dog 10 in Fig. 16 in the installed state with removed tap hole plate 113. The feed dog 10 is inserted into the insertion element 80, which in turn is inserted into the feed dog holder 30. The insertion element 80 is connected to the feed dog holder 30 by means of the fastening elements 82, 83. In Fig. 18 It is shown that the distance between the shoulders 84, 85 of the insertion element 80 corresponds exactly to the width of the conveyor 10, so that the feed dog 10 can be held precisely in the recess 81. Two similar fastening elements 40 extend from the inner bottom of the insertion element 80 through the corresponding holes 12, 13 of the conveyor 10 therethrough. As a result, the position of the conveyor 10 can be fixed in the x direction. By the fasteners 82, 83, the position of the insertion is set in the x and y direction. If the side edges of the conveyor 10 are fitted exactly between the inner edges of the paragraphs 84, 85, also the position of the conveyor is set in the x direction.
If at least one of the holes 12, 13 is formed as a hole with play, the position of the conveyor 10 in the y-direction may still be variable. By means of the adjusting element 50, therefore, the position of the conveyor 10 can be set in the y-direction. For this purpose, the locking element 53 in the in Fig. 18 are shown locking position. The locking element 53 may be integrally formed with the head end 51 and / or the neck 52, but it may also be rotatable about a fixed neck. The feed dog 10 may have a corresponding recess 90, which is intended for engagement of the locking element 53. A Entriegelungsausnehmung 75 may be provided in the feed dog holder 30 to receive the locking member 53 in its unlocked position, for example, when the feed dog 10 is replaced by another feed dog.

Fig. 19 shows a section through the feed dog 10 according to Fig. 16 in the installed state in perspective view. The feed dog 10 rests on the bearing surface formed by the recess 81 of the insertion element 80. The insertion element 80 lies on the recess 31 formed by the feed dog holder 30 on. From the adjustment member 50, only a part of the locking element 53 is visible, namely a part of the tab which protrudes through a corresponding opening in the tap hole plate 113. Fig. 19 also shows an opening in the stitch hole plate for one of the feed dog arms, namely the outer web 16. The second feed dog, that is, the outer web 17 according to Fig. 5 is not visible in the present illustration because it lies in front of the cutting plane. The locking element 53 is formed in combination with the tap hole plate 113 so that only when the lock has been fully actuated, the locking element 53 engages in the recess of the needle plate 113 so that it is ensured that the needle plate 113 in incomplete, so not complete, Lock can not be mounted.

Fig. 20 shows a perspective view of a fifth embodiment according to the invention in an exploded view. The device for manually changing a conveyor 10 for a sewing machine according to Fig. 20 includes the feed dog 10 and a feed dog holder 30. The feed dog 10 is receivable in a recess 31 of the feed dog holder 30. The feed dog holder 30 is arranged in a free arm 103 of the sewing machine 101, which is shown in FIG Fig. 15 is shown. The feed dog 10 is by means of a fastener 40 fastened in a recess 81 of an insertion element 80, wherein the fastening element 40 can be releasably held in the insertion member 80. The fastening element 40 may be formed, for example, as a dovetail groove. In each of these dovetail groove, a side edge of the conveyor 10 can be inserted. The width of the conveyor 10 may in the region of the side edges of the top, ie the side that comes in contact with the fabric during operation, to the opposite side, in the drawing so the bottom increase. As a result, the feed dog 10 is held captive in the insertion. According to the embodiment in Fig. 20 For example, various transporters 10 may be secured by two fasteners 40 in the insertion member 80. The dovetail groove may include flanks that form part of a cone whose apex points in the direction of the webs 16, 17, 18 of the conveyor 10. By a conical embodiment of the dovetail groove, the feed dog 10 can be centered in the dovetail groove.

The insertion element 80 is received in the feed dog holder 30. In particular, the insertion element 80 is received in a recess 31 of the feed dog holder 30. The insertion element 80 is by means of one or more fasteners 82, 83 in the feed dog holder 30 held. The orientation of the conveyor takes place via the insert element 80 ex works. The adjusting element 50 serves only as a lock. The adjusting element 50 can also be held in the hole by a clearance fit or a pin lock in this embodiment.

In Fig. 20 an adjusting element 50 is shown, through which the feed dog 10 in its position relative to the recess 31 and / or the insertion element 80 is adjustable. The adjustment 50 according to Fig. 20 is formed as a lever member having a head end 51 and a neck 52. The head end 51 has a larger diameter than the neck 52. The neck 52 may have an external thread. The neck 52 may be held at least partially in a bore 33 which is mounted in the recess 31 or the recess 81. The bore 33 may be formed as a threaded bore. The adjustment member 50 may include a locking member 53. The locking element 53 serves the locking with respect to in the Fig. 20 Not shown tap hole plate 113. The locking element 53 according to the present embodiment consists of the head end 51, which is in contact with a spring element which is attached to the feed dog 10 when the feed dog 10 is in its installed position.

The feed dog is locked in the installed position by bringing the lever element of the adjusting element 50 into a position in which the head end 51 bears on the in Fig. 21 shown spring element 19 presses and this biases. The adjusting element 50 includes a stop 57, the installed state is particularly vertically aligned and protrudes into a corresponding opening 140 of the needle plate 113, which is in Fig. 19 in a similar manner for the tab of the locking element 53 is shown.

The spring element 19 can be inserted into the feed dog 10, i. be formed as an insert element or it may be formed as part of the conveyor 10. In particular, the spring element can be produced from the base material by a locally acting material treatment method, for example by hardening, zone melting, tempering, exposure to radiation or other methods familiar to the person skilled in the art for locally changing the microstructure of the material of the transporter.

As in Fig. 1 For example, the adjustment member 50 may include an eccentric disc, or the head end 51 may be formed as an eccentric, which is shown in FIG Fig. 20 or Fig. 21 is shown. The head end 51 may comprise a receiving element for an actuating key. According to a further embodiment, the head end 51 a rough profile or a grooving, which makes it possible to rotate the head end 51 manually to bring the locking member 53 in the desired position, whereby a determination of the feed dog 10 with respect to the needle plate 113 can be made. Also, the tab or stop 57 may serve as a handle or gripping member for a tool to move the adjustment member 53 to the desired position.

The feed dog 10 can thus be aligned in accordance with the contour located in the stitch hole plate 113 of the sewing machine 101. Such a tap hole plate 113 is for example in Fig. 19 shown partially cut. In particular, it can be avoided by this fine adjustment that the feed dog 10 comes into contact with an edge of the needle plate 113 during operation and the feed dog 10 or the needle plate 113 can be damaged. In particular, the tap hole plate may include an opening 140 that has been created, for example, by a milling process. Only with complete locking of the conveyor, the tap hole plate 113 can be mounted, since only the stopper 57 fits into the opening 140.

When two fasteners 40 are used, the feed dog may be in one of the fasteners 40 be free of play, so with fit, be recorded and in the other fastener 40 without fit, so be included with game. In particular, when the fastening element is designed as a dovetail groove, it is possible to prevent a movement of the conveyor in the x-direction and in the z-direction. The movement in the y-direction can according to the in Fig. 20, 21 illustrated embodiment can be prevented by the bracing of the spring element 19 by means of the adjusting element 50.

A fixing element, which may be formed, for example, as a magnetic element, in particular as a magnetic pin, may be used to fix the feed dog 10 and / or the insertion element 80 in the correct position before the locking of the feed dog 10 by the fastening element or elements 40 takes place or the locking of the insertion element 80 by the fasteners 82, 83 takes place.

An advantage of this embodiment is that allow by fasteners, which are designed as a form-locking guide elements for the conveyor, such as a dovetail groove for a corresponding edge of the conveyor, a precise alignment of the conveyor in both the x-direction and in the y-direction. In particular, the Web elements 16, 17, 18 of the conveyor aligned parallel to the y-axis, that is, they are aligned exactly in the feed direction of the material. The alignment in the x-direction, ie in the longitudinal direction of the free arm 103, takes place exactly on the corresponding recess or the corresponding recesses in the needle hole plate 113.

It will be apparent to those skilled in the art that many other modifications are possible in addition to the described embodiments without departing from the inventive concept. The object of the invention is thus not limited by the foregoing description and is determined by the scope of protection defined by the claims. The widest possible reading of the claims is decisive for the interpretation of the claims or the description. In particular, the terms "contain" or "include" are to be interpreted as referring to elements, components or steps in a non-limiting sense, to indicate that the elements, components or steps may be present or may be used, that they can be combined with other elements, components or steps that are not explicitly mentioned. If the claims refer to an element or a component from a group that may consist of A, B, C, ... N elements or components, this shall Be interpreted such that only a single element of this group is required, and not a combination of A and N, B and N or any other combination of two or more elements or components of this group.

Claims (15)

A sewing machine (101) comprising a device for manually changing a feed dog (10), comprising the feed dog (10) and a feed dog holder (30), the feed dog holder (30) being located in a free arm (103) associated with the sewing machine, wherein the feed dog (10) is receivable in a recess (31, 81) of the feed dog holder (30), the feed dog (10) located in the cutout (31, 81) having a bearing surface (15) parallel to the surface of a sewing cloth pad, a needle hole plate (113) may be arranged, wherein the feed dog has a base surface, which is arranged opposite to the support surface (15), wherein the base surface on a base surface of the recess (31, 81) in the assembled state at least partially rests, wherein the tap hole plate (113) can be formed at least partially from the surface of the free arm (103), wherein the support surface (15) in an opening (140) of the Sti The feed dog (10) can be fastened in the recess (31, 81) by means of a fastening element (40, 82, 83) or an adjusting element (50), so that the bearing surface (15) in FIG Aligned substantially parallel to the surface of the tap hole plate (113), characterized in that the fastening element (40, 82, 83) or the adjusting element (50) is releasably held in the feed dog holder (30). Apparatus according to claim 1, characterized in that the opening (140) has a greater length than the feed dog (10) or guided through the opening web (16, 17, 18) of the conveyor (10), so that the position of the conveyor ( 10) is variable with respect to the opening (140). Device according to one of claims 1 or 2, characterized in that the opening (140) has a greater width than the feed dog (10), so that the width of the conveyor (10) is variable. Device according to one of the preceding claims,
characterized in that the recess (31, 81) has at least one side edge which delimits the base surface at its edge, wherein the feed dog (10) is at least partially received by the side edge of the recess (31, 81). Device according to one of the preceding claims, characterized in that the feed dog (10) by the adjusting element (50) in its position relative to the recess (31, 81) is adjustable or lockable. Apparatus according to claim 5, characterized in that the adjusting element (50) comprises an eccentric, wherein the eccentric is guided on a pin. Apparatus according to claim 5, characterized in that the adjusting element (50) is formed as part of a pin which is held in a threaded bore (34) in the feed dog holder (30). Apparatus according to claim 5, characterized in that the adjusting element (50) comprises a locking element (53). Device according to one of the preceding claims, characterized in that the fastening element (40) comprises an element from the group of screws, nuts, threaded bolts, bolts, guide rails. Device according to one of the preceding claims, characterized in that the fastening element (40) in the recess (31) of the feed dog holder (30) is at least partially held. Device according to one of the preceding claims,
characterized in that the fastening element (40) is held at least partially in an insertion element (80). Device according to one of the preceding claims 9 to 11, characterized in that the fastening element (40) can be secured against loss by means of a securing element. Device according to one of the preceding claims,
characterized in that the feed dog (10) can be positioned in the recess (31, 81) by means of a fixing element (86). Device according to one of the preceding claims, characterized in that the feed dog (10) by means of a locking element (53) in the recess (31, 81) is positionable. Device according to one of claims 13 or 14,
characterized in that the fixing element (86) contains a magnet or a ferromagnetic region and / or the locking element (53) is rotatably arranged in the feed dog holder (30).

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