阅读说明：本技术 用于相对于缝料的结构调节线缝廓形的位置的方法 (Method for adjusting the position of a seam profile relative to the structure of a material to be sewn ) 是由 G·杰格 B·贝克 于 2019-04-08 设计创作，主要内容包括：本发明涉及一种用于调节线缝廓形的位置的方法以及一种用于执行该方法的设备,其中,线缝廓形相对于缝料的结构的位置调节基于基准缝料的结构和工作缝料的结构的比较数据。(The invention relates to a method for adjusting the position of a seam profile and to a device for carrying out the method, wherein the position adjustment of the seam profile relative to the structure of the work material is based on comparison data of the structure of a reference material and the structure of a working material.)

1. A method for adjusting the position of a seam profile relative to the structure of a work piece, said method comprising the steps of:

-detecting a reference position of the seam construction from a reference seam having these constructions,

-generating a reference structure data item based on the detected structure reference position,

-after generating the reference structure data item: the working sewing material is sewn by utilizing the sewing program,

-wherein, before sewing the working seam material, the following steps are performed to prepare the sewing program:

-detecting a working position of the work joint compound's joint compound structure corresponding to the reference joint compound's joint compound structure,

-generating work configuration data items based on the detected configuration work positions,

-comparing the working position with the reference position on the basis of the comparison between the reference structure data item and the working structure data item,

-adapting the parameter data of the sewing program on the basis of the deviation detected in the comparison between the reference structure data item and the work structure data item, and

-sewing the work seam material using the adapted sewing program.

2. Method according to claim 1, characterized in that at least one deviation between the reference structure data item and the working structure data item from the group is taken into account:

-displacement of the working seam relative to the reference seam along a first sewing coordinate,

-displacement of the working seam relative to the reference seam along a second sewing coordinate, which is perpendicular to the first sewing coordinate,

-a difference in size of the work configuration data item relative to the reference configuration data item along at least one of said sewing coordinates,

-an angular deviation of the extension of the work structure data item relative to the reference structure data item along the coordinates, along the line connecting the start and end points of the respective data item, and

-a difference in size of the extension of the work structure data item relative to the reference structure data item along the line connecting the coordinates along the start and end points of the respective data item.

3. The method according to claim 1 or 2, characterized in that a work material is inserted into the work material frame, wherein the reference position and the working position are detected while the work material is inserted.

4. A sewing device (1) for carrying out the method according to any one of claims 1 to 3, having:

-a sewing machine for sewing the fabric,

-a frame (8) for the sewing material,

-a camera system (9), and

-a programmable controller (12) in signal connection with the sewing machine and the camera system.

Technical Field

The invention relates to a method for adjusting the position of a seam contour/seam course (NaHtvelauf) relative to the structure of a material to be sewn and to a sewing machine for carrying out the method.

Background

From the publications EP 1997945 a1, EP 0971061 a1, US 2012/022602 a1 and GB 2240193 a1, sewing machines are known which have a camera for detecting a seam material, wherein the seam profile to be sewn is determined on the basis of the detected image data.

It has been found that, in particular in the case of stitch material with a structure that is critical in position (for example leather with a perforation pattern), the application of the structure (i.e. for example the application of the perforation pattern) cannot be easily arranged in a reproducible manner on the stitch material because of the inhomogeneous nature of the stitch material. With the devices and methods known from the prior art, reproducible sewing of the seam relative to the structure is not possible anyway, given the high demands on the accuracy of the position of the seam relative to the structure.

DE 3535644C 2 discloses a method for stitching along the contour of a pattern applied to a planar elastic material and a device for carrying out the method. DE 68907167T 2 discloses a method and a device for feeding sheet-like material. DE 10236581 a1 discloses a method for compensating for pattern distortions on a planar work material, which is spread on a conveying surface. US 5,205,232 discloses an apparatus for edge identification and sewing. US 2009/0188414 a1 discloses a sewing machine and a control program for a sewing machine. DE 4203558 a1 discloses a device for correcting the position of a material to be sewn. DE 4205070 a1 discloses a method for positioning and feeding a seam material. DE 102015116112 a1 discloses a shape recognition device and a sewing machine.

Disclosure of Invention

It is an object of the present invention to provide a method with which sufficiently precise position adjustment of the seam profile relative to the structure of the seam material can be achieved even with high precision requirements. This object is achieved by the features of claim 1.

The invention is based on the recognition that the sewing program can be adapted (modified) in such a way that a positional adjustment of the seam profile relative to the structure of the work material is effected on the basis of data obtained from a comparison of the structures of the reference material and the work material.

In a method for adjusting the position of a seam contour relative to the structure of a seam material, reference positions of the seam material structure are first detected from reference seam materials having these structures. Based on the detected reference position, a reference structure data item/data record is generated using the detected structure reference position. Sewing the work material with a sewing program after the generation of the reference structure data item, wherein the sewing program can be read in or selected before the sewing of the work material, wherein the following steps are performed to prepare the sewing program before the sewing of the work material:

detecting a working position of the seam material structure of the working seam material corresponding to the seam material structure of the reference seam material,

-generating a work structure data item based on the detected work position of the structure,

-comparing the working position and the reference position on the basis of the comparison between the reference structure data item and the working structure data item,

-adapting the parameter data of the sewing program in dependence on the deviation between the reference structure data item and the working structure data item detected in the comparison.

The work material is then sewn using the adapted sewing program.

The reference joint compound is different from the working joint compound. In the case of a reference joint compound on the one hand and a corresponding working joint compound on the other hand, they therefore relate to different parts of the joint compound.

Examples of the structure of the slot are perforations in the slot or patterns or coloured patterns, in particular irregular patterns, in the slot. Advantageously, the position of a plurality of successive perforations and/or the length or direction of a series of perforations or the angle between two sections of a series of perforations can be detected and processed. The contour of the pattern or color pattern in the seam material can be recognized and the seam contour can be adapted to this contour.

It has been recognized that an adjustment method that compares an initially generated reference configuration data item with a working configuration data item of the material to be sewn at present, which is generated in dependence on the detected configuration working position, maintains the data processing expenditure that the respective position adjustment method can be easily controlled even in the case of high precision requirements and speed requirements for mass production. The work structure data items may be generated in a manner that is adapted to the structure present in the work material. In this case, the properties of the structure, such as the current arrangement or pattern details of the seam perforation, can be taken into account.

The adaptation of the sewing program can be further improved by means of the method according to claim 2. The position adjustment of the seam profile is further improved. The seam image is optimized. Exactly one of the deviation types "displacement along the first sewing coordinate (coordinate direction, coordinate axis)", "displacement along the second sewing coordinate", "size difference of structure data item", "angle deviation", or "size difference of structure data item extension (Erstreckung)" may be used. Alternatively, more than one of these deviation types may be used, for example a combination of two of these deviation types, a combination of three of these deviation types, a combination of four of these deviation types or a combination of all the mentioned deviation types.

The structure data item deviations described in claim 2 have been proven in practice for structures typically present on the seam material. The consideration of the deviation of the displacement along at least one sewing coordinate ensures that no undesirable deviations of the seam profile occur when comparing the reference seam material with the current working seam material. The consideration of the size difference can ensure, for example, that different image proportions do not play an undesirable role in the position adjustment when detecting the reference seam on the one hand and the working seam on the other hand. This applies correspondingly also when taking into account angular or size differences between the start and end points of the data item.

The insertion of the joint compound into the joint compound frame according to claim 3 ensures reproducible positioning of the joint compound.

Another object of the invention is to provide a sewing apparatus for carrying out said method.

This object is achieved by the features of claim 4.

The camera system ensures that the structural, position-critical seam material is detected in a positionally correct manner in such a way that the seam can be sewn along a predetermined path relative to the structure of the seam material. The camera system may be a stereo camera system. The camera system may be designed such that the type of deviation can be checked in real time during the sewing process.

Drawings

One embodiment is explained in detail with reference to the drawings. The figures show that:

figure 1 shows the sewing machine illustrated with the omission of individual components,

figure 2 shows a view at line II-II of the sewing device according to figure 1,

FIG. 3 shows a partial view of a work seam material having a work structure, an

Fig. 4 shows a flow chart of a method for adjusting the position of a seam profile.

Detailed Description

Fig. 1 and 2 schematically show a sewing apparatus 1. Such a sewing device 1 may be, for example, a CNC sewing device of the present applicant, in particular a CNC sewing device KL 110.

For ease of understanding the positional relationship, cartesian xyz coordinate systems are given in fig. 1 to 3, respectively. The x-axis is perpendicular to and extends into the plane of the drawing of fig. 1. The y direction extends to the left in fig. 1, while the z direction extends upward in fig. 1.

As shown in fig. 1, the sewing apparatus 1 has a sewing head 2 of a sewing machine. Furthermore, the sewing machine comprises a needle bar 3 with a sewing needle 4, wherein the sewing head 2 is supported in a rotatable manner about the z-axis. Coaxially and opposite to the z-axis, a schematically indicated wire gripper 5 is arranged.

A sewing material 6 with a structure 7 is located between the sewing needle 4 and the thread clamp 5. The joint compound 6 is tightened on the joint compound frame 8. The stitch frame 8 is movable in the x-y plane relative to the sewing head 2. Due to the rotatability of the sewing head 2 and the movability of the sewing frame 8 in the x-y plane, three degrees of freedom are created, so that a seam profile in all sewing directions can be realized in the x-y plane.

The sewing material 6 can be a reference sewing material or a working sewing material. A reference seam is a seam having a structure, wherein the structure is applied to an optimized material that is closely toleranced. A sewing program is generated based on the reference sewing material. This is explained in more detail below with reference to fig. 4. The working seam is a seam to be sewn having a structure corresponding to that of the reference seam, wherein possible inhomogeneities may be present. These non-uniformities are typically created by the application of structure (e.g., perforations) as the material deforms, such as by stretching and/or compressing, as the structure is applied. This results in a change in the position of the structure of the working seam relative to the structure of the reference seam. The non-uniformity may also be a result of a change in the position of the working joint compound in the joint compound frame relative to the reference joint compound in the joint compound frame. Due to this unevenness, the sewing program needs to be adjusted. This is also explained in more detail below with reference to fig. 4.

A camera system 9 is arranged at a distance from the sewing needle 4 along the y-axis and is in signal connection 10 with a control 12 (in particular a CNC control) of the sewing machine 1, which is present in a computer unit 11. In particular, the camera system 9 can have two cameras, which are not shown in detail. The camera system 9 can be designed as a stereo camera system or as a smart camera.

A memory element 13, in particular a RAM memory, in which at least one sewing program is stored is provided in the computer unit 11. Furthermore, evaluation software 14 is provided on the computer unit 11 or in the camera system 9 itself, which evaluation software serves for evaluating the images, in particular the reference image and the working image generated, and for determining the reference structure data item and the working structure data item. The evaluation software 14 exchanges parameters and data with a sewing program which is executed with the sewing device 1 when sewing a seam. The communication of the camera system 9 with the controller 12 can be realized, for example, by means of the USB (universal serial bus) standard via reading and writing files on a data carrier or by means of a TCP (transmission control protocol) connection.

The controller 12 informs the evaluation software 14 which sewing program should be adapted. The camera system 9 may notify the controller 12 of the operation preparation, error, success, and the like. On this basis, the controller 12 can start the evaluation of the camera system 9. After the evaluation is completed, the camera system 9 transmits the adaptation parameters for the selected sewing program to the controller 12 by means of the operating parameter values, for example for compensating the displacement of the individual points due to the stretching, strain and/or compression of the seam material 6. In this way, an automatic adaptation of the parameter values is provided for adapting the sewing program. Each sewing process is adapted based on the evaluation of the camera system 9. Before each sewing process, an image region 15 of the unsewn material 6 is detected/recorded by means of the camera system 9, from which image region an image to be evaluated is generated. Depending on the desired seam contour relative to the structure 7, the image area 15 can cover the entire seam material 6 or at least a partial area of the seam material 6. Accordingly, an image of the entire seam material 6 or an image of a part of the seam material 6 can then be generated.

Fig. 3 shows a partial view of an unsewn working seam 16 stretched over the seam frame 8, which has spaced perforations 17 in the form of squares 18 on the top. Between the squares 18 on the top end, gaps 19 exist, in which gaps the seam contour should be arranged, wherein the seam contour should be arranged as centrally as possible between the squares 18 on the top end. As can be seen in fig. 3, the squares 18 on the top, placed along the y-axis, move along the x-axis. At the same time, the square 18 on the top, placed along the x-axis, also moves along the y-axis.

Prior to sewing, an image of the working seam material 16 is generated by the camera system 9. The image becomes a working image. A work configuration data item is generated from the work image, which is compared with a reference configuration data item generated from a reference image, not shown, that has been generated. In the present case, all the blanks are detected, i.e. all the reference blanks and all the working blanks, in order to generate the reference images and also the working images accordingly.

The method for adjusting the position of the seam profile relative to the structure 7 of the seam material 6 is described below with reference to fig. 4.

First, in step S₁In the above method, the reference position of the structure of the work material is detected from the reference work material having the above structures. For this purpose, a reference image of the reference seam material is first generated by the camera system 9. In this case, all the reference joint compound is detected. Subsequently, the reference image is loaded into the camera system 9 and recognition of the seam material structure 17, for example a perforation, is started.

In order to detect the structure reference position, a measuring line is set up in the camera system 9. The measurement lines are established by marking the individual perforations in the reference image. The structure can be detected by means of a measuring line. This is achieved in particular by detecting the starting and ending points in the x-direction, the starting and ending points in the y-direction and/or the angle of the measuring line. In general, for example, 99 measurement lines can be generated, wherein each measurement line can be specified with a different individual measured value (i.e., parameter).

Then in step S₂Wherein the reference structure data item is generated based on the detected structure reference position.

For this purpose, the individual measuring lines are stored in the form of a pixel or scaled coordinate list and with respect to the sewing program. It is thereby possible to rediscover the measuring lines in the image to be evaluated and to evaluate the change in position of the individual perforations relative to a reference. For each parameter of each measurement line, an identifier for communicating with the controller 12 is determined.

Then, in step S₃A preparation step of starting a sewing program.

In step S₄The controller 12 notifies the camera system 9 which sewing program should be corrected. The camera system 9 reports the following states, i.e., operation readiness, evaluation, success, and error, to the controller 12. The controller 12 in turn reports to the camera system 9 the status that camera evaluation is to begin.

At the same timeThe latter step S₅The operating position of the work joint compound 16 joint compound structure 18 is detected, which corresponds to the joint compound structure of the reference joint compound. For this purpose, an image of the working material 16 that is not sewn is generated by the camera system 9. The image becomes a working image.

For detecting the working position, a measuring line is generated in the camera system 9. To this end, a working image is first loaded into the camera system 9 and the identification of the perforation 17 in the working seam material 16 is started. The measuring lines can then be set up automatically in the working image by marking the individual perforations 17. Here, the measurement line data of the reference image detection may be used. The setting up of the measuring line may be similar to step S₁The process is carried out.

Subsequently, in step S₆Generating the work structure data item based on the detected work position of the structure. This is similar to step S₂And is performed based on the reference configuration data item stored for the corresponding sewing program.

Subsequently, in step S₇The comparison of the work position and the reference position is performed based on a comparison between the reference structure data item and the work structure data item. Corresponding deviation parameters are obtained from the comparison, on the basis of which the sewing program can be adapted.

In step S₈In the method, parameter data of the sewing program are adapted on the basis of a deviation between the reference structure data item and the working structure data item detected in the comparison.

The deviation between the reference structure data item and the working structure data item is taken into account by at least one deviation type from the group:

-displacement of the working seam relative to the reference seam along the sewing coordinate,

-displacement of the working seam relative to the reference seam along a second sewing coordinate, which is perpendicular to the first sewing coordinate,

-a difference in size of the work configuration data item relative to the reference configuration data item along at least one of said sewing coordinates,

-the angular deviation of the extension of the work configuration data item relative to the reference configuration data item along the sewing coordinates, along the line connection of the start and end points of the respective data item, and

-a difference in size of the extension of the work configuration data item relative to the reference configuration data item along the sewing coordinates, along the line connection of the start and end points of the respective data item.

The adaptation of the sewing program is performed by means of the camera system 9. The camera system 9 changes the selected sewing program by manipulating the parameter values in the sewing program. This is achieved according to at least one of the above-mentioned deviation types or according to a combination of at least two of the above-mentioned deviation types. For example, the sewing program is stored on a computer unit 11 which is commonly used by the camera system 9 and the controller 12. Alternatively, the camera system 9 can also transmit the parameter values directly to the controller 12, which then influences the currently selected sewing program. In this way, corrections for each sewing process can be achieved based on camera evaluation.

For this purpose, the parameters to be used must be entered in a distributed manner in the sewing program. Based on the evaluation of the first measurement results for material samples that have been specified to different tolerances, it is now possible to calculate specified parameters in the sewing program. Standard-compliant instructions provided by the controller 12 are used for this purpose. These instructions may cause the entire sewing program and/or the individual seam profiles and/or the individual start and end points of the seam to be displaced. These instructions may also result in stretching or compressing of the stitchbonded material. Further, the angle error may be compensated for using the command. The corresponding correction command is input in the sewing program in such a way that a change of the reference sewing program is effected.

Subsequently, in step S₉The work material 16 is sewn using the adapted sewing program. The sewing now follows a precisely predetermined path relative to the structure 18 of the work material 16.