JP2007222484A - Sewing machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enable the optional correction of a position of a guide for guiding a string material to the bottom of a needle. <P>SOLUTION: The sewing machine is provided with a sewing mechanism for sewing the string material to an object to be sewn along an advance direction of sewing based on sewing data and the guide 16 rotatable around the axis of a sewing needle 8. The guide 16 positions itself on the front side of the advance direction to guide the material. From the sewing data, the advance direction of the next stitch sewing is calculated (S1). A correction angle is obtained from an optional ratio of an angle difference between the next stitch advance direction and the last one to an angle difference obtained from multiplication of an optional correction (S2). The correction angle is added to the next stitch advance direction (S3). A difference between the value in which the correction angle is added to the next stitch advance direction and a present rotation angle of the guide 16 is obtained (S4). The obtained value is the rotation angle of the guide 16 corrected through the correction angle. A rotation position of the guide 16 is controlled from the rotation angle. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a sewing machine that can sew a string-like material such as a tape or a cord to a workpiece, and more particularly, to an improvement in control of a guide body that guides the string-like material to a needle base position.

Conventionally, a sewing machine that can sew a string-like material such as a tape or a cord onto a cloth is known. In this type of sewing machine, the sewing machine head has a needle bar that has a sewing needle at the lower end and is driven up and down, a presser foot that is moved up and down in synchronization with the vertical drive of the needle bar, and the needle bar that is coaxial. A rotating body assembled on the center and freely rotating around its axis, and rotated together with the rotating body, guides the string-like material to the needle base position of the sewing needle (position corresponding to the needle tip of the sewing needle). A guide body, and the rotation body is rotationally controlled so as to position the guide body ahead of the sewing progress direction calculated based on the sewing data, whereby the guide body guides the string-like material to the needle base position. It was supposed to be possible. Then, the needle bar and the presser body are driven up and down to perform the sewing operation, so that the string-like material guided to the needle base position is sewn to the sewing object (cloth or the like) (for example, the following patent document) 1).
JP-A-8-299639

An example of sewing a string-like material according to the conventional technique is shown in FIG. In FIG. 6, a symbol T indicates a flat and wide “tape material” as an example of a string-like material, and a symbol P indicates a “seam” when the tape material T is sewn to a sewing object (for example, a fabric). . In addition, FIG. 6 shows a mode in which the tape material T is bent and sewn as an example of a sewing mode of the tape material T. One of the curved portions of the tape material T is circled by a broken line, and the broken line A symbol A is given to the enclosing portion. FIGS. 7A and 7B are enlarged views showing an example of the sewing state of the curved portion of the tape material T corresponding to the portion A in FIG. As shown in FIG. 6, according to the sewing mode, the seam P is formed at the center position in the width direction of the tape material T. In this case, the sewing machine is sewn by controlling the rotational position of the guide body so that the sewing needle falls to the center position in the width direction of the tape material T. Therefore, originally, the seam P must be formed at the center in the width direction of the tape material T even in the curved portion A of the tape material T as shown in FIG.
However, in actuality, as shown in FIG. 7B, in the curved portion A, the tape material T is displaced outward in the bending direction with respect to the seam P, and the position of the seam P is the width of the tape material T. There was the inconvenience that it shifted from the center of the direction. This inconvenience is that when the tape material T is guided into a curved shape, the tape material T cannot sufficiently follow the rotational displacement of the guide body because the tape material T is biased to one side of the guide body, etc. It was caused because it was located outside the curve from the position where it should be guided. This inconvenience becomes more prominent as the tape material T is more curved, i.e., the tape material T tends to be displaced, and the displacement tends to increase. Further, the degree of deviation of the tape material T differs depending on the material, shape, etc. of the tape material T.

  The present invention has been made in view of the above points, and in a sewing machine that can sew a string-like material such as a tape or a cord to a sewing object, a guide body that guides the string-like material to a needle base position. An object of the present invention is to provide a sewing machine that can correct the position.

  The present invention relates to a sewing mechanism for sewing a string-like material to a workpiece based on sewing data, and for guiding the string-like material in a direction corresponding to the sewing progress direction at a sewing position by the sewing mechanism. A guide body, guide data calculation means for calculating guide data according to the sewing progress direction based on the sewing data, correction means for correcting the guide data based on correction parameters, and guide data corrected by the correction means. And a positioning means for positioning the guide body based on the sewing machine.

  Further, in the sewing machine according to the present invention, the guide body is rotationally displaced relative to the sewing mechanism, and the guide data calculating means uses the guide body according to the sewing progress direction as the guide data. The correction means is a means for adding the correction parameter to the calculated rotation angle, and the positioning means is based on the rotation angle corrected by the correction means. It may be a means for positioning the rotational position of the guide body.

  According to the present invention, the guide data according to the sewing progress direction is calculated based on the sewing data by the guide data calculating means, the guide data is corrected based on the correction parameter by the correcting means, and the guide corrected by the correcting means is corrected. By positioning the guide body based on the data, the position where the string-like material is sewn on the workpiece can be changed according to the correction parameter. The guide body is typically rotationally displaced relative to the sewing mechanism, and the correction means adds a correction parameter to the rotation angle of the guide body calculated by the guide data calculation means. The rotational position of the guide body can be corrected (changed). Further, the correction means may include a correction parameter generation means for generating a correction parameter based on a change amount of one to a plurality of stitches of guide data. Therefore, even when the string-like material is bent and sewed, the position where the string-like material is guided by correcting the rotation position of the guide body is determined by the degree to which the string-like material is bent, the material and shape of the string-like material, etc. According to the method, it can be arbitrarily changed to produce an excellent effect that the formation position of the seam can be corrected. Thereby, for example, it is possible to effectively prevent a shift in the formation position of the seam. Alternatively, by changing the formation position of the seam, it is possible to arbitrarily change the sewing mode of the tape material and provide a stitched design with a different taste.

Hereinafter, an example of an embodiment of the present invention will be described in detail with reference to the accompanying drawings.
FIG. 1 is a front view of a multi-head sewing machine according to this embodiment. The multi-head sewing machine shown in FIG. 1 includes a plurality of sewing heads H (eight in the example shown) that can sew a string-like material. Each sewing head H is attached to the front side of the upper frame 2 arranged above the long sewing table 1 extending in the horizontal direction, and is arranged at equal intervals along the horizontal direction of the frame 2. ing. Below each sewing head H, a hook base 4 that supports the hook 3 is provided corresponding to each sewing head H. Each of these pot bases 4 is disposed at substantially the same height as the sewing machine table 1. A sewing frame 5 is placed on the upper surface of the sewing machine table 1 to stretch and hold the workpiece. The sewing frame 5 is assembled to a drive mechanism (not shown) disposed below the sewing machine table 1, and is driven in the front-rear and left-right directions with respect to the multi-head sewing machine body by the drive mechanism. In this specification, the left-right direction (the left-right direction in FIG. 1) with respect to the sewing machine body is the “X direction”, and the front-rear direction (the vertical direction in FIG. 1) with respect to the sewing machine body is the “Y direction”. .

  One sewing machine spindle 6 shared by each sewing head H is attached so as to penetrate each sewing head H. As the sewing machine main shaft 6 rotates, the sewing needles provided in the sewing heads H are reciprocated up and down. Then, by the cooperation of the sewing needles that reciprocate up and down in each sewing head H and the hooks 3 that are rotated in the hook base 4 corresponding to each sewing head H, the workpiece to be stretched and held on the sewing frame 5 Sewing on (for example, cloth) is executed for each sewing head H.

  2 is a partial cross-sectional side view of one of the sewing heads H shown in FIG. 1 as viewed from the left side. The left-right direction in FIG. 2 corresponds to the front-rear direction (Y direction) of the sewing machine body. The sewing head H is provided with a needle bar 7 that moves up and down according to the rotation of the sewing machine spindle 6 provided through the sewing head H, and a sewing needle 8 is fixed to the lower end of the needle bar 7. Is done. The support cylinder 9 provided on the outer periphery of the needle bar 7 is guided by the inner peripheral surface of the fixed sleeve 10 fixed to the lower part of the sewing head H, and is moved up and down relative to the needle bar 7. The needle bar 7 can be rotated around the axis. An engagement ring 11 is fixed to the outer periphery of the upper end portion of the support cylinder 9, and the end of the drive arm 13 is engaged with the engagement ring 11. The drive arm 13 is a member that moves up and down in accordance with the drive of the motor 12, and transmits the up and down movement in accordance with the drive of the motor 12 to the support cylinder 9 via the engagement ring 11. A presser foot support 14 is fixed to the lower end of the support tube 9. The presser foot support 14 is a member formed in a bifurcated shape. A key groove 14a extending vertically is formed on one outer surface of the bifurcated shape, and a presser foot 15 is fixed to the other lower portion. The The presser foot 15 extends downward from the presser foot support 14 toward the needle plate 25, and a string-like material (tape material T) is moved to the needle base position of the sewing needle 8 at the lower end of the presser foot 15. A guide 16 that functions as a guide body that guides is attached. The needle plate 25 is fixed to the upper surface of the pot base 4 as is well known.

  The presser foot support 14 is moved up and down integrally with the vertical movement of the support cylinder 9 driven by the motor 12. Accordingly, the presser foot 15 fixed to the presser foot support 14 is moved up and down as the motor 12 is driven. The up-and-down movement of the presser foot 15 by the motor 12 is performed at a predetermined timing with respect to the raising and lowering driving of the needle bar 7. Thus, it is well known that the presser foot 15 performs the presser foot function during a sewing operation described later.

  A rotating cylinder 17 is provided on the outer periphery of the fixed sleeve 10 so as to be rotatable about its axis, and a timing pulley portion 18 is formed on the outer periphery of the upper end of the rotating cylinder 17. A key member 19 is fixed to the lower end of the rotary cylinder 17, and the tip of the key member 19 engages with a key groove 14 a formed on the outer surface of the presser foot support 14. The engagement of the key member 19 with the key groove 14a functions as a mechanism for transmitting the rotation of the rotary cylinder 17 to the presser foot support 14 as described later. A bobbin bracket 20 is fixed to the outer periphery of the rotary cylinder 17, and a bobbin 21 around which the tape material T is wound is rotatably supported by the bobbin bracket 20.

  The timing pulley portion 18 of the rotary cylinder 17 is connected via a timing belt 24 to a drive pulley 23 that is rotated according to the driving of the motor 22, and the rotation of the driving pulley 23 according to the driving of the motor 22 is performed. Is transmitted to the rotating cylinder 17. When the rotating cylinder 17 rotates, the bobbin bracket 20 (bobbin 21) fixed to the outer periphery thereof rotates. Further, since the tip of the key member 19 fixed to the rotary cylinder 17 is engaged with the key groove 14 a formed in the presser foot support 14, the rotation of the rotary cylinder 17 is performed via the key member 19. It is transmitted to the support 14. Accordingly, the presser foot support 14 and the guide 16 fixed to the presser foot support 14 rotate integrally with the rotary cylinder 17. That is, the guide 16 rotates around the axis of the needle bar 7 integrally with the rotary cylinder 17, the presser foot support 14, and the bobbin bracket 20 according to the drive of the motor 22.

  As described above, since the key groove 14a extends in the vertical direction, the cloth presser support 14 is allowed to move relative to the key member 19 in the vertical direction. Accordingly, the presser foot support 14 rotates integrally with the rotation of the rotary cylinder 17 by the engagement of the key member 19 and the key groove 14a, and moves up and down integrally with the vertical movement of the support cylinder 9 (key member 19). Can move up and down relatively).

When the tape material T is sewn in the multi-head sewing machine having the sewing head H configured as described above, the bobbin 21 around which the tape material T is wound is set on the bobbin bracket 20, and the tape material T is drawn from the set bobbin 21. And the tape material T is guided to the needle base position of the sewing needle 8 by passing it through the guide 16. The needle base position is a position corresponding to the needle tip of the sewing needle 8.
In this state, the sewing frame 5 is controlled to move in the X direction and the Y direction based on predetermined sewing data, and the needle bar 7 is driven up and down by the rotation of the sewing machine main shaft 6 so that the sewing needle 8 and the shuttle 3 can cooperate. A known sewing operation is performed by the action, and the tape material T is sewed on the sewing product stretched on the sewing frame 5 by the formed stitch.

  As described above, the rotation position of the bobbin 21 and the guide 16 with respect to the needle bar 7 is displaced by rotating the rotating cylinder 17 by the motor 22. At the time of the sewing operation, the guide 16 is positioned at a rotational position on the front side in the sewing progressing direction with respect to the sewing needle 8, and guides the tape material T to the needle base position at the rotational position. Guide along the direction of sewing. The sewing advance direction corresponds to a relative advance angle of the sewing head H with respect to the movement of the sewing frame 5. Therefore, by controlling the rotation angle of the rotary cylinder 17 in accordance with the relative advance angle of the sewing head H with respect to the movement of the sewing frame 5, the guide 16 is positioned forward in the sewing advance direction with respect to the sewing needle 8. be able to. The rotation control of the rotary cylinder 17 is performed for the stitching operation for each stitch. As described below, the present invention is characterized in that the rotational position of the guide 16 can be arbitrarily changed by arbitrarily correcting the rotational angle of the rotary cylinder 17 calculated based on the sewing data. There is.

  In the sewing machine, various operations related to the sewing operation are controlled by a control device (not shown) including a CPU, a ROM, and a RAM. The control device controls the operation of each part of the sewing machine for each stitch based on the sewing data. The processing for calculating the rotation angle for controlling the rotation of the rotary cylinder 17 described below can be configured in the form of a software program executed by the control device, for example.

FIG. 3 is a flowchart showing an example of a calculation process procedure for calculating a rotation angle for controlling the rotation of the rotary cylinder 17. The process of FIG. 3 is a process executed to obtain the rotation angle of the rotary cylinder 17 for the next stitch (next stitch) to be formed at the time of the sewing operation.
In step S1, based on the sewing data (X-direction movement data and Y-direction movement data) corresponding to the next stitch, the relative advance angle of the sewing head H with respect to the movement of the sewing frame 5 performed to form the next stitch (Advance angle of the next stitch) is obtained by calculation. In this embodiment, it is assumed that the rotation position at which the bobbin 21 and the guide 16 are positioned at a predetermined position on the right side when viewed from the front of the sewing machine with respect to the needle bar 7 is set as the initial rotation position of the rotary cylinder 17. When the power of the sewing machine is turned on, the rotational position of the rotary cylinder 17 is adjusted by driving the motor 22 so that the rotary cylinder 17 is positioned at the initial rotational position. The advancing angle of the next stitch obtained in step S1 is expressed by a rotation angle in which the relative advancing direction of the sewing head H with respect to the movement of the sewing frame 5 is based on the initial rotation position of the rotary cylinder 17 (angle 0 °). Value. In this specification, the rotation angle from the initial rotation position is referred to as “absolute angle”.

In step S2, “correction angle (correction parameter)” according to this embodiment is obtained by performing “correction angle calculation processing” shown in FIG. 4 based on the advance angle of the next stitch obtained in step S1.
FIG. 4 is a flowchart showing an example of the procedure of the “correction angle calculation process” in step S2. In step S10 of FIG. 4, the angle difference between the advance angle of the next stitch obtained in step S1 of FIG. 3 and the advance angle of the sewing head H in the stitch immediately before the next stitch (advance angle of the previous stitch) is calculated. Obtained by calculation. The advance angle of the next stitch and the advance angle of the immediately preceding stitch respectively represent the relative advance direction of the sewing head H with respect to the sewing frame 5 as the rotation angle from the initial rotation position (reference = angle 0 °) of the rotary cylinder 17. It is the value. By calculating the angle difference between the advance angle of the next stitch and the advance angle of the immediately preceding stitch by the calculation in step S10, a relative angle change amount (relative angle) from the advance angle of the immediately preceding stitch in the advance angle of the next stitch is obtained. obtain.

In step S11, the “correction angle” for the advance angle of the next stitch is calculated by multiplying the angle difference obtained in step S10 by an arbitrary correction value. The correction value is a parameter for setting the ratio of “correction angle” to the angle difference obtained in step S10, and can be set in the range of “−200% to + 200%”, for example. In addition, the operator may be able to set an arbitrary correction value using appropriate setting means such as an operation panel (not shown). By this step S11, it is possible to obtain a “correction angle” obtained by increasing / decreasing the angle difference between the advance angle of the next stitch and the advance angle of the immediately preceding stitch at a rate corresponding to an arbitrary correction value. Therefore, the value of the correction angle is increased or decreased in accordance with the angle difference between the advance angle of the next stitch and the advance angle of the previous stitch, in other words, the rotation angle (relative angle) of the rotary cylinder 17 when forming the next stitch. Will be.
As described above, when the tape material T is sewed in a curved shape, the tighter the curvature of the tape material T, the larger the angle difference between the advance angle of the next stitch with respect to the advance angle of the previous stitch, and the tape P against the seam P. Conventionally, there has been an inconvenience that the tendency of the material T to shift to the outside is increased (see FIGS. 6 and 7). On the other hand, according to this embodiment, the value of the correction angle is increased or decreased according to the rotation angle of the rotary cylinder 17 (the amount of change in the advance angle of the next stitch with respect to the advance angle of the immediately preceding stitch). The tighter the curve, the greater the amount of correction based on the correction angle. Accordingly, the tape material T can be more reliably positioned at an arbitrary position.

  Returning to FIG. 3, in step S3, the correction angle obtained in step S2 (the process of FIG. 4) is added to the advance angle of the next stitch obtained in step S1. This value is a value representing the rotation angle of the rotary cylinder 17 in the next stitch as an absolute angle from the initial rotation position. In step S4, the angle difference between the value obtained by the calculation in step S3 and the value obtained by adding the correction angle for the immediately preceding stitch to the advance angle of the immediately preceding stitch, that is, the rotation angle of the rotating cylinder 17 in the next stitch. The angle difference between the (absolute angle) and the absolute angle of the rotating cylinder 17 in the immediately preceding stitch (in other words, the absolute angle of the rotating cylinder 17 at the present time) is obtained by calculation. As a result, the relative angle from the current rotational position of the rotating cylinder 17 to the rotational position to be positioned in the next stitch can be obtained.

  In this embodiment, the various values obtained in the above processing (the advance angle of the next stitch, the correction angle, and the added value of both) are used as data for the previous stitch at the next activation of the rotation angle calculation process. Therefore, it is assumed that it is temporarily stored in an appropriate memory such as a RAM.

  When the rotation angle (relative angle) of the rotary cylinder 17 in the next stitch is obtained in step S4 in FIG. 3, the rotation angle calculation process for the next stitch is completed, and the value of the relative angle obtained in step S4 is obtained. Accordingly, the motor 22 is driven and the rotation cylinder 17 is controlled to rotate. Since the relative angle of the rotary cylinder 17 obtained in step S4 is a value corrected by a correction angle that increases or decreases according to the rotation angle (angle change amount) of the rotary cylinder 17, the guide 16 moves in the sewing progress direction (sewing machine). The rotation position (corrected rotation position) corrected based on the correction angle with respect to the relative traveling angle of the head H). Accordingly, the guide 16 guides the tape material T along the sewing progress direction by guiding the tape material T to the needle base position at the corrected rotation position. As a result, even when the tape material T is sewn in a curved shape, the position where the tape material T is guided (rotation position of the guide 16) is appropriately corrected, and the tape material T is more reliably guided to a desired position. be able to.

  FIG. 5 is a diagram schematically showing an example of stitch formation when the tape material T is sewed in a curved shape, and shows a state seen from directly above the front of the sewing head H. In the figure, the needle base position for each stitch is indicated by a black circle, and symbols P1, P2, P3, P4, and P5 are assigned in the order of sewing progress. That is, stitch sewing proceeds from the stitch P1 to P5 in order. It is assumed that the initial rotation position of the rotary cylinder 17 is the right side of the needle base position in FIG. 5, and the advance angle from the stitch P1 to P2 corresponds to the absolute angle of the initial rotation position of the rotary cylinder 17 = 0 °.

  With reference to FIG. 5, an example of a specific procedure of the rotation angle calculation process and the rotation control of the rotary cylinder 17 according to this embodiment will be described by taking the case of performing the stitch P4 as an example. When the stitch P4 is performed, the next stitch is P4 and the immediately preceding stitch is P3. Further, it is assumed that the correction value is set to + 50%. Further, the angles θ1 to θ5, θ1 ′, and θ4 ′ shown in FIG. 5 are respectively defined as follows.

θ1: The relative advance angle of the sewing head H in the next stitch.
θ2: The angle difference between the advance angle of the next stitch (= θ1) and the advance angle of the previous stitch (= θ1 ′ described later).
θ3: Correction angle.
θ4: rotation angle of the guide 16 in the next stitch (absolute angle from the initial rotation position of the rotating cylinder 17).
θ5: The rotation angle of the guide 16 in the next stitch (absolute angle from the initial rotation position of the rotating cylinder 17), and the rotation angle of the guide 16 in the immediately preceding stitch (absolute angle from the initial rotation position of the rotating cylinder 17 = θ4 ′) Angle difference. That is, the relative angle at which the rotating cylinder 17 should be rotated in the next stitch.
θ1 ′: relative advance angle of the sewing head H in the immediately preceding stitch.
θ4 ′: The rotation angle of the guide 16 in the immediately preceding stitch (absolute angle from the initial rotation position of the rotating cylinder 17).

  First, based on the X and Y movement data for the stitch P4, the relative advance angle θ1 of the sewing head H from the previous stitch P3 to the next stitch P4 is calculated (step S1 in FIG. 3). In FIG. 5, the relative advance angle θ1 of the sewing head H to reach the next stitch P4 is indicated by a broken line arrow between P3 and P4, which corresponds to the sewing progress direction of the stitch P4. Next, an angle difference θ2 between the advance angle θ1 of the next stitch P4 and the advance angle θ1 ′ of the immediately preceding stitch P3 is obtained by calculation (step S10 in FIG. 4), and the operator arbitrarily sets this angle difference θ2. A correction angle θ3 is obtained by multiplying the correction value (step S11 in FIG. 4). Here, since the correction value is set to “+ 50%”, the correction angle θ3 = “θ2 / 2”.

  Then, by adding the correction angle θ3 (θ1 + θ3) to the relative advance angle θ1 of the sewing head H from the previous stitch P3 to the next stitch P4, the rotation angle (absolutely) of the next cylinder P4 (Angle) θ4 is obtained (step S3 in FIG. 3). Then, the angle difference between the absolute angle θ4 of the rotary cylinder 17 in the next stitch P4 and the absolute angle θ4 ′ of the rotary cylinder 17 when the immediately preceding stitch P3 is formed (that is, the absolute angle of the rotational position of the rotary cylinder 17 at the present time). θ5 is calculated (step S4 in FIG. 3). The rotating cylinder 17 is controlled to rotate based on the calculated angle difference θ5. By the rotation control of the rotary cylinder 17, the guide 16 is positioned at the rotational position of the absolute angle θ4, and the solid arrow indicated by P3 is the starting point with respect to the relative traveling angle of the sewing head H indicated by the broken arrows P3-P4. It will be located in the front of the direction. The direction of the solid arrow starting from P3 corresponds to the direction in which the relative traveling angle of the sewing head H indicated by the dashed arrows P3-P4 is corrected by the correction angle θ3, as shown in FIG.

  In FIG. 5, each broken line arrow indicates a relative advance angle of the sewing head H when forming each stitch P2, P3, P4 and P5, and each solid line arrow indicates each stitch P2, P3, P4. And the rotation position of the guide 16 at the time of forming P5 is shown, respectively. As apparent from FIG. 5, in the example of FIG. 5, the guide 16 is positioned in front of the direction indicated by the solid line arrow by the correction based on the correction angle θ3, so that the tape material is curved in the sewing advance direction. You can guide to the inside. As described above, in the conventional technique, the guide 16 is positioned in front of the relative traveling direction of the sewing head H indicated by the broken-line arrow, so that the tape material T is displaced outward in the bending direction with respect to the seam P. That is, there is a disadvantage that the seam P is formed closer to the inside of the curve (see FIG. 7B). On the other hand, according to this embodiment, since the rotational position of the guide 16 is corrected, the position of the tape material can be corrected closer to the inside of the curve in the sewing progressing direction. Can be formed at the center in the width direction.

As described above, according to this embodiment, the rotation cylinder 17 is controlled to rotate so that the guide 16 is positioned in the direction in which the correction angle is added to the relative advance angle of the sewing head H, so that the The sewing position (formation position) in the width direction of the tape material T can be changed according to the correction value arbitrarily set by the operator. Therefore, even when the tape material is curved and sewed, the position where the tape material is guided can be arbitrarily changed by correcting the rotation position of the guide 16, and the seam can be formed at the center in the width direction of the tape material. it can. Therefore, even when the tape material is bent and sewed, it is possible to effectively prevent the shift of the seam formation position.
In contrast to the example of FIG. 5, by setting a negative correction value, the rotation cylinder 17 is controlled to rotate so that the guide 16 is positioned outside the curve in the sewing progress direction, and the tape material is guided. By changing the stitching direction to the outer side of the curve in the sewing direction, the seam of the curved portion is intentionally formed closer to the inner side in the width direction of the tape material so that the outer side of the tape material rises. Can do. That is, in this way, by arbitrarily changing the rotational position of the guide 16 according to the present invention, it is possible to arbitrarily change the sewing mode of the tape material and to provide a sewn design with a different taste. .

  In the above-described embodiment, the correction value setting range is “−200% to + 200%”. However, the numerical value range is merely an example, and the correction value setting range is not limited thereto. Further, in order to generate a correction angle in step S11 of FIG. 4, the angle difference (change amount) between the advance angle of the next stitch and the advance angle of the immediately preceding stitch, that is, the ratio to the change amount of the advance angle for each stitch. However, the present invention is not limited to this, and the correction angle may be calculated as a ratio to the amount of change in the advance angle for each stitch. Further, the correction angle is not limited to the configuration in which the correction angle is calculated as a ratio with respect to the change amount of the advance angle for each of one to a plurality of stitches. The calculation may be performed as follows. As another configuration example, a data table for outputting a correction angle corresponding to the change amount is stored in advance, and a correction angle is determined using the data table, or an arbitrary value for the change amount is determined. The correction angle may be determined by calculating with the coefficient. As yet another configuration example, a correction value may be recorded in advance in the sewing data, and the correction value may be read when sewing data to be sewn is selected. Moreover, in the said Example, although the example which changes the said correction angle based on the advance angle (sewing progress direction) for every stitch was shown, not only this but a correction angle is set based on the shape, material, etc. of the said string-like material. It is good also as a structure to determine. Further, the correction may be performed at a fixed correction angle by setting an arbitrary correction angle value by the operator.

  In the above embodiment, the guide 16 is assumed to be rotationally displaced in accordance with the drive of the motor 22, and the example in which the position for guiding the tape material is set according to the rotational position of the guide 16 is shown. As long as the tape material is guided in a direction corresponding to the sewing advancement direction, not only rotational displacement but also linear displacement, swing displacement, or any other displacement may be used. Moreover, in the said Example, although the tape raw material was shown as an example of a string-like material, what kind of thing may be sufficient as long as the raw material used as a sewing object has a string shape. Alternatively, the string-like material may be guided by swinging to the left and right of the needle base position for each reciprocation of the needle bar, and sequentially sewn onto the fabric by so-called plover stitching.

1 is a front view of a multi-head sewing machine according to an embodiment of the present invention. Side surface partial sectional drawing which expands and shows one of the sewing heads H in the multi-head sewing machine which concerns on the Example. The flowchart which shows an example of the procedure of the rotation angle calculation process which concerns on the Example. The flowchart which shows an example of the procedure of the correction angle calculation process which concerns on the same Example. The figure which shows typically the example of stitch formation when the tape raw material T is sewed in the curve in the Example. It is explanatory drawing of a prior art, Comprising: The example of a string-like material sewing by a prior art is shown. FIG. 7 is an explanatory diagram of the prior art, in which (a) is a diagram for explaining a desirable seam formation example in the curved portion of the string-like material shown in FIG. 6, and (b) is an undesired seam in the curved portion. The figure for demonstrating deviation | shift.

Explanation of symbols

H Sewing head, 1 sewing machine table, 2 frames, 3 hooks, 4 hook base, 5 sewing frame, 6 sewing machine main shaft, 7 needle bar (part of sewing mechanism), 8 sewing needle (part of sewing mechanism), 9 support Cylinder, 10 Fixed sleeve, 11 Engagement ring, 12 Motor, 13 Drive arm, 14 Cloth presser support body, 15 Cloth presser body, 16 Guide (guide body), 17 Rotating cylinder, 18 Timing pulley section, 19 Key member, 20 Bobbin bracket, 21 Bobbin, 22 Motor (part of control means), 23 Drive pulley, 24 Timing belt, 25 Needle plate, T tape material (string material), P seam

Claims (3)

A sewing mechanism for sewing the string-like material to the sewing product based on the sewing data;
A guide for guiding the string-like material in a direction according to the sewing progress direction at a sewing position by the sewing mechanism;
Guide data calculating means for calculating guide data according to the sewing progress direction based on the sewing data;
Correction means for correcting the guidance data based on correction parameters;
A sewing machine comprising: positioning means for positioning the guide body based on the guide data corrected by the correction means.   The sewing machine according to claim 1, wherein the correction unit includes a correction parameter generation unit that generates the correction parameter based on an amount of change of the guide data for one to a plurality of stitches. The guide body is rotationally displaced relative to the sewing mechanism,
The guide position data calculating means is means for calculating a rotation angle of the guide body according to the sewing progress direction as the guide position data,
The correction means is means for adding the correction parameter to the calculated rotation angle,
The sewing machine according to claim 1, wherein the positioning unit is a unit that positions a rotation position of the guide body based on a rotation angle corrected by the correction unit.

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