JP2010035988A - Binding sewing machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To correct right and left error generated in a corner knife. <P>SOLUTION: A binding sewing machine has a cloth feeding mechanism 20 for carrying an object to be sewn, a needle vertical moving mechanism 40 forming two linear sewing lines TL, TR in the object to be sewn, a moving knife mechanism 50 forming a linear cutting line S, and a corner knife mechanism 100 forming gradient cutting lines VFL, VFR, VRL, VRR in both the end portions of the linear cutting line. The corner knife mechanism has corner knife holders 105 at one end portion side and the other end portion side of the linear cutting line, a longitudinal feeding mechanism 90 moving the one corner knife holder along a cloth feeding direction F, a lateral feeding mechanism 120 selecting the plurality of corner knives of the respective corner knife holders by moving the same in a direction perpendicular to the cloth feeding direction, and a correction control means carrying out correction using the lateral feeding mechanism 120 obtaining perpendicular direction error in gradient cut line forming position from the error of the corner knife holder input from an error input means 85 in a predetermined moving point. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an edge stitch sewing machine for forming oblique cuts.

A bead stitch sewing machine is a sewing machine for performing bead stitches that is often applied to the opening of a pocket of a suit, for example, and includes two seams that are parallel to each other with the bead piled on the body cloth. And a straight cut formed between two seams parallel to them, and at both ends of the straight cut, diagonal cuts from the end of the straight cut toward the end of each seam Formation is performed (for example, refer to Patent Document 1).
In the formation of the diagonal cut, it is required that the centers of the pair of diagonal cuts formed on both sides of the cloth feed in the direction orthogonal to the straight line cut coincide with the straight cut.
For this reason, in the conventional edge stitch sewing machine, measures are taken so as not to cause a position error of the oblique cut in the direction orthogonal to the cloth feeding direction by adjusting the assembly position of the corner knife.
JP 2006-218189 A

However, in the case of an edge stitch sewing machine that can move the corner knife along the cloth feeding direction, for example, even if the corner knife is assembled and adjusted at the origin position in the corner knife's cloth feeding direction, the corner knife is fed, for example. If there is an error based on assembly accuracy or part processing accuracy, such as the guide moved along the direction is not parallel to the cloth feed direction, an error will occur if the corner knife is moved to the cutting position. was there. In this case, the center of the pair of oblique cuts does not coincide with the end of the straight cut, and there is a disadvantage that the quality of the sewing product is deteriorated.
In addition, since the amount of error varies depending on the cutting position of the corner knife in the cloth feed direction, an attempt to eliminate the error by assembling the corner knife each time the cutting position is changed causes the corner knife to change. There is a problem that it is necessary to perform an error measurement for each cutting position in the cloth feeding direction and an operation of assembling the corner knife, which cannot endure the trouble.

  An object of the present invention is to eliminate an error in a direction orthogonal to the cloth feed direction of the oblique cut.

  According to the first aspect of the present invention, there is provided a cloth feed mechanism that holds and conveys the body cloth and the ball cloth, and two stitches that form two straight seams parallel to the body cloth and the ball cloth along the cloth feed direction. A needle up-and-down moving mechanism for moving the needle up and down, a moving knife mechanism for forming a straight cut along the cloth feed direction between the two straight stitches, an end of the two straight stitches and the straight cut In the edge stitch sewing machine provided with a corner knife mechanism for forming a diagonal cut between the end portions, the corner knife mechanism individually forms a diagonal cut at one end and the other end of the straight cut. Two corner knife holding bodies, a vertical feeding mechanism for moving one corner knife holding body along the cloth feed direction according to the length of the straight cut, and each corner knife holding body, Forming multiple types of diagonal cuts A plurality of corner knives that move in a direction perpendicular to the straight line cuts, and a transverse feed mechanism that selects the corner knives to be used. An error input means for inputting an error of a corner knife position generated in a direction orthogonal to the straight line break at a distant movement point, a storage means for storing a predetermined distance from the origin to the movement point, and a corner for performing the movement For the cutting operation by the corner knife held by the knife holding body, the amount of error generated at the cutting execution position of the corner knife holding body is calculated from the relationship between the input error and the distance from the origin position to the moving point. And a correction control means for correcting the position by the lateral feed mechanism to form an oblique cut.

  The “plural types of oblique cuts” indicate cases where the inclination angle with respect to the straight cuts is different, the cutting lengths are different, or both are different.

  The invention described in claim 2 has the same configuration as that of the invention described in claim 1, and further includes setting means for setting and inputting a distance from the origin position to the moving point.

  The invention according to claim 3 has the same configuration as that of the invention according to claim 1, and the storage means has a distance from the origin to the moving point, from the origin to the maximum moving position of the corner knife holder. The distance is memorized.

  The invention according to claim 4 has the same configuration as that of the invention according to claim 1, 2, or 3, and the error input means can input an error at two moving points, and the correction control means For the cutting operation by the corner knife held by the corner knife holder that moves along the cloth feed direction, the corner knife is determined from the relationship between the distance from the origin position to each moving point and the error at each moving point. An amount of error generated at the cutting execution position of the holding body is obtained, and the oblique feed is formed by correcting the position by the lateral feed mechanism.

In the invention according to claim 1, when forming the oblique cut, one corner knife holding body is moved along the cloth feed direction, and the corner knife of each corner knife holding body is inclined at both ends of the straight cut. The vertical feed mechanism is controlled so as to be arranged in a formable manner.
Further, in each corner knife holding body, the lateral feed mechanism is controlled so as to move and position each corner knife in a direction orthogonal to the cloth feed for selecting a predetermined corner knife.
On the other hand, an error in the position of the corner knife in the direction perpendicular to the cloth feed direction (the direction of contact / separation with respect to the straight cut) when the corner knife holder is located at a moving point that is a predetermined distance away from the origin position is manually performed by the operator. When the measurement error is input by the error input means, the cutting control means calculates the ratio of the error in the orthogonal direction of the corner knife generated with respect to the moving distance of the corner knife holder. Further, an error in the orthogonal direction generated in the corner knife due to the movement positioning of the corner knife holder in the cloth feeding direction is calculated from the ratio.
Further, the correction control means corrects the position corresponding to the calculated error under the control of the lateral feed mechanism.
Then, diagonal cuts are formed by the corner knife at the corrected position.

As described above, even if the moving direction of the corner knife holder becomes non-parallel to the cloth feed direction due to assembly accuracy, parts accuracy, etc., even if an error occurs in the orthogonal direction due to the movement of the corner knife holder, If the error amount is measured once at the point, the error amount generated in the orthogonal direction can be obtained regardless of the position of the corner knife holder, and correction can be made based on this.
Accordingly, it is possible to improve the sewing quality by optimizing the formation position of the diagonal cuts by the corner knife without performing complicated work.
In addition, since the error in the direction perpendicular to the cloth feed direction is corrected by the lateral feed mechanism for selecting the corner knife, a mechanism structure for performing a new correction is unnecessary, and the implementation cost can be greatly reduced. Is possible.

  Since the invention according to claim 2 includes setting means for setting and inputting the distance from the origin position to the moving point, the error can be measured at an arbitrary position.

  In the invention according to claim 3, since the storage means stores the distance from the origin to the maximum movement position of the corner knife holding body as the distance from the origin to the movement point, the movement distance of the corner knife holding body and its orthogonal direction When calculating the error ratio, the error ratio can be calculated by calculating the maximum movement distance and the maximum error caused by this, so that a more accurate value can be determined and the position of the corner knife can be corrected. It becomes possible to carry out more accurately.

According to the fourth aspect of the present invention, it is possible to obtain the ratio between the moving distance of the corner knife holder and the position error of the corner knife in the orthogonal direction based on the error at the two moving points. For this reason, for example, even when an error has already occurred in the orthogonal direction at the origin position of the corner knife holder, the error ratio can be calculated by eliminating the influence, and a more accurate value can be obtained. The position correction can be performed with higher accuracy.
When quoting the invention of claim 2, the respective distances to the two moving points are set by the setting means. In the case of quoting the invention of claim 3, the error is calculated by setting one of the two movement points as the arrival position at the maximum movement distance of the corner knife holder.

(Explanation regarding the bead stitching performed by the bead stitching machine)
Hereinafter, a bead stitch sewing machine 10 according to an embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a perspective view showing an overall schematic configuration of a bead stitch sewing machine 10. In the present embodiment, the respective directions are determined with reference to the XYZ axes shown in the drawings, and the Z-axis direction coincides with the vertical movement direction of the center knife, which will be described later, and is a plane for performing the sewing work. Is perpendicular to the Z-axis direction and is parallel to the work plane and the direction in which the cloth is fed is the X-axis direction, and the direction parallel to the work plane and perpendicular to the X-axis direction is the Y-axis direction.

  2 and 3 show a straight cut S by a center knife and a diagonal cut VFL, VFR, VRL, VRR by a corner knife and a straight stitch TL, TR by two needles in a bead stitch forming an oblique pocket opening. FIG. 2 is an explanatory diagram showing the relationship of the arrangement of the edges, and the edge stitch forming the pocket opening can be performed by the two types of methods shown in FIGS. As shown in the drawing, the traveling direction of the cloth feeding direction F during sewing is the front side of the cloth feeding direction, and the opposite direction is the rear side of the cloth feeding direction, and is one direction along the Y-axis direction and facing the cloth feeding direction. The following description will be given with the left hand direction as the left side and the other direction along the Y-axis direction, which faces the cloth feed direction and the right hand direction as the right side.

The bead stitch sewing machine 10 sews a cloth B to the body cloth M by two parallel straight stitches TL and TR formed by the two needles 41 and 41, and in the feed direction F of these cloths. It is a sewing machine that forms a linear cut S that becomes a pocket hole along the side and a substantially V-shaped corner cut made up of a pair of diagonal cuts at both ends of the cut S.
In the edge stitch forming the rectangular pocket opening, both the front and rear ends of both straight stitches are formed in a state where they are aligned in the cloth feeding direction.
On the other hand, in the case of the edge stitch forming the oblique pocket opening, each of the front and rear ends of one of the straight seams (the right side seam TR in FIG. 3) is more than the front and rear ends of the other straight seam. It is formed so as to be located on the front side. Here, the amount of deviation in the cloth feeding direction from the rear end of the straight seam TR to the rear end of the straight seam TL is referred to as rear deviation CR, and the front side of the straight seam TL from the front end of the straight seam TR. The amount of deviation in the cloth feed direction to the end is assumed to be the front side deviation CF.

  2, the slanted cut VFR is formed from the front end FE of the straight cut S to the front end of the right straight stitch TR, and the left straight stitch from the front end FE of the straight cut S is formed. A diagonal cut VFL is formed over the front end of the TL. Further, an oblique cut VRR is formed from the rear end RE of the straight cut S to the rear end of the right straight stitch TR, and the rear end of the left straight stitch TL from the rear end RE of the straight cut S. A diagonal cut VRL is formed through.

  In addition, in the edge stitch shown in FIG. 3, a diagonal cut VFR is formed from the front end of the straight cut S to the front end of the right straight stitch TR, and the left straight stitch TL from the front end of the straight cut S is formed. A diagonal cut VFL is formed over the front end. Further, a diagonal cut VRR is formed from the rear end portion of the straight cut S to the rear end portion of the right straight seam TR, and the diagonal cut from the rear end portion of the straight cut S to the rear end portion of the left straight seam TL. A cut VRL is formed. The diagonal cuts VFR and VFL constituting the corner cut are set so that the length in the cloth feed direction is longer by the deviation CF in the VFR, and the diagonal cuts VRR and VRL constituting the corner cut are VRL. Is set so that the length in the cloth feeding direction is increased by the deviation CR.

The bead-sewn sewing machine 10 can selectively execute the two types of the method shown in FIG. 2 and the method shown in FIG. 3 when performing the bead stitching for forming the oblique pocket opening. .
In addition, this edge stitch sewing machine 10 performs the stitch which does not provide deviation in any of the front end portion and the rear end portion, that is, the bead stitch where the two straight stitches form a rectangular opening with no deviation in the front and rear. It goes without saying that it is also possible to do this.

(Overall configuration of the stitching machine)
The ball edge sewing machine 10 includes a sewing machine table 11 serving as a sewing work table, a sewing machine frame 12 disposed on the sewing machine table 11, and a cloth feeding mechanism that feeds a cloth made of the body cloth M and the ball cloth B. As a large press feed mechanism 20, a binder 30 that presses the top of the cloth B from the upper side of the cloth M, and a stitch forming mechanism that performs needle drop on both sides of the cut S in the vicinity of the front end portion in the cloth feed direction F of the binder 30. As shown in FIG. 1, a sewing product comprising a body fabric M and a ball cloth B, which are placed in a state where a center knife 51 as a moving knife is moved up and down on the front side in the cloth feeding direction F of each sewing needle 41, is placed. A center knife mechanism 50 as a moving knife mechanism for forming a cut S in the corner and a corner for forming a substantially V-shaped cut V at both ends of a linear cut S (hereinafter also referred to as a straight cut S). A scan mechanism 100, and an operation control unit 80 for controlling the above units.
Each part is described in detail below.

(Sewing table and sewing frame)
The sewing machine table 11 is used in a horizontal state with its upper surface parallel to the XY plane. The upper surface of the sewing machine table 11 is formed in a long rectangular shape along the cloth feeding direction F, that is, the X-axis direction. A large press feed mechanism 20 and a binder 30 are disposed on the sewing machine table 11, and a corner knife mechanism 100 is disposed on the lower side of the sewing machine table 11.
A needle plate 13 is provided at a position below the two sewing needles 41, 41 in the sewing machine table 11. The needle plate 13 is provided with a needle hole corresponding to each of the two needles 41 and 41, and a horizontal hook (not shown) is provided below each needle hole. That is, the sewing thread inserted into each of the sewing needles 41, 41 is captured by the corresponding horizontal hook at the lower side of the needle plate 13, and is entangled with the lower thread fed from the horizontal hook so that the sewing is performed. It has become.
Furthermore, a slit into which the center knife 51 is inserted is formed in the middle of the two needle holes of the needle plate 13 and on the front side in the cloth feeding direction F, and in cooperation with the center knife 51 inside the slit. A fixed knife (not shown) for cutting the fabric is disposed.

  The sewing machine frame 12 extends along the Y-axis direction from the bed portion 12a disposed immediately next to the middle position in the longitudinal direction of the sewing machine table 11, the vertical body portion 12b erected from the bed portion, and the upper end portion of the vertical body portion 12b. The arm portion 12c is extended, and the main components of the needle vertical movement mechanism 40 and the center knife mechanism 50 are stored in the arm portion 12c. Further, the two needles 41 and 41 and the center knife 51 are supported in a suspended manner from the lower end portion on the distal end side of the arm portion 12c.

(Needle vertical movement mechanism)
FIG. 4 is a perspective view of the needle vertical movement mechanism 40. The needle up-and-down moving mechanism 40 includes two sewing needles 41 and 41 constituting two needles, two needle bars 42 that individually hold the sewing needles 41 at the lower end, and each needle bar 42 can be moved up and down. 10, a needle bar holder 44 that simultaneously holds the two needle bars 42, a sewing machine spindle motor 45 as a sewing machine motor serving as a drive source for the sewing needle vertical movement, and a sewing machine spindle motor 45 (FIG. 10). ), A rotating spindle 47 that is fixedly connected to one end portion of the sewing machine spindle 46 and that rotates, and one end portion is connected to a position eccentric from the rotation center of the rotating weight 47 and the other end. And a crank rod 48 connected to a needle bar holder 44.

  The sewing machine main shaft 46 is also rotatably supported in the Y-axis direction inside the arm portion 12 c, and a rotational driving force of full rotation is applied by the sewing machine main shaft motor 45. When the sewing machine main shaft 46 is rotated, the rotary weight 47 rotates in the same manner, and one end portion of the crank rod 48 performs a circular motion around the sewing machine main shaft 46, and the other end portion has a circular motion Z on one end side. Only the axial movement component is transmitted to the needle bar holder 44 so that each needle bar 42 reciprocates up and down.

Further, the needle bar holder 44 has a built-in latch mechanism (not shown) capable of switching between holding and releasing the needle bars 42, 42, and holding and holding the needle bars 42 at the upper end of the support frame 49. A holding mechanism (not shown) capable of switching the release is incorporated. Further, the latch mechanism and the holding mechanism can be switched between holding and releasing the needle bar 42 by applying a predetermined operation from the outside, and a needle switching solenoid 43 that performs a switching operation on each mechanism (see FIG. 10). Is attached to the support frame 49.
With the needle switching solenoid 43, both the needle bars 42, 42 are held by the latch mechanism, one needle bar 42 is held by the latch mechanism, and the other needle bar 42 is held by the holding mechanism, It is possible to switch between the state in which one needle bar 42 is held by the holding mechanism and the other needle bar 42 is held by the latch mechanism. In any state, the needle bar held by the needle bar holder 44 is The needle bar that moves up and down and is held by the latch mechanism stops near the top dead center.
When performing slant-shaped bead stitching, the three holding states are switched at a predetermined timing to form a deviation in the cloth feed direction at the front and rear ends of the left and right straight stitches TL and TR. It is possible to do.

  The needle bars 42 and 42 hold the sewing needles 41 and 41 so that their positions can be adjusted along the Y-axis direction. Thereby, the interval in the Y-axis direction of the above-described straight stitches TL and TR can be adjusted. Such adjustment is normally performed so that each of the straight seams TL and TR is equidistant from the straight cut S.

(Center knife mechanism)
FIG. 5 is a perspective view of the needle up-and-down moving mechanism 40 and the center knife mechanism 50 in a severable state.
The center knife mechanism 50 is fixed to the center knife 51 that forms a linear cut S by moving up and down, and is fixed below the needle plate 13 and slidably contacts the center knife 51 to promote cutting of the fabrics B and M. A scalpel, a scalpel bar 52 provided with a center scalpel 51 at the lower end and supported so as to be slidable along the Z-axis direction in the arm portion 12c; a scalpel motor 57 that is a stepping motor for moving the center scalpel 51 up and down; A plurality of link bodies 59 that transmit a vertical movement driving force to the knife rod 52 via an eccentric cam 58 that is eccentrically attached to the output shaft 57b of the knife motor 57, and a state where the center knife 51 can be cut (lower position). An air cylinder 65 as an actuator serving as a drive source for switching operation to the cutting restriction state (upper position) and a plunger when the air cylinder 65 protrudes are provided. And a stopper 68 for stopping at the position.

  The center knife mechanism 50 is in a severable state in which the rotational driving force of the knife motor 57 is converted into an up and down reciprocating motion to the center knife 51 and transmitted when the air cylinder 65 is in the retracted position (the state shown in FIG. 5). When the air cylinder 65 is in the forward position (not shown), it is possible to switch to a cutting restriction state in which the rotational driving force of the knife motor 57 is not transmitted to the center knife 51.

When the knife motor 57 is driven to rotate while the air cylinder 65 is retracted, the knife rod 52 and the center knife are interposed via the plurality of link bodies 59 by the eccentric cam 58 provided on the output shaft 57b directed in the Y-axis direction. The cutting operation is performed by moving 51 up and down.
On the other hand, when the air cylinder 65 is in the advanced state, the plurality of link bodies 59 are arranged so that the power of the female motor 57 is not transmitted to the female bar 52 and the center knife 51 is retracted above the needle plate 13. Is maintained.
Accordingly, the air knife 65 is driven so that the center knife 51 can be switched between the cutting-capable state and the cutting restriction state.

(binder)
The binder 30 includes a bottom plate portion 31 that is a long flat plate, a standing plate portion 32 that is erected vertically on the upper surface along the longitudinal direction of the bottom plate portion 31, and a front end portion in the cloth feeding direction of the standing plate portion 32. In addition, a guide member 33 that guides the ball cloth B while avoiding the center knife 51 and a vertical guide that guides the both ends in the width direction of the ball cloth B to be fed along both surfaces of the upright plate portion 32 (illustrated). Abbreviation).
The binder 30 is supported by a support mechanism (not shown) including an air cylinder, and is retracted away from the position below the needles 41 and 41 when not in use, as shown in FIG. And in use, it is set to the needle plate position by driving the air cylinder.

The bottom plate portion 31 is formed in a rectangular shape, and is supported so that, when in use, the longitudinal direction thereof is parallel to the X-axis direction and the bottom surface thereof is placed facing the upper surface of the sewing machine table 11. ing. In addition, a substantially U-shaped notch (not shown) is formed at the front end portion of the bottom plate portion 31 in the cloth feeding direction so that the two sewing needles 41 and 41 respectively perform needle dropping.
The standing plate portion 32 is entirely flat except for a portion in the vicinity of the guide member 33, and on the upper surface of the bottom plate portion 31, the bottom plate portion is located at an intermediate position in the width direction (Y-axis direction) of the bottom plate portion 31. It is erected vertically with the longitudinal direction aligned with 31. That is, the binder 30 is integrally formed so that the bottom plate portion 31 and the upright plate portion 32 have an inverted T shape when viewed from the longitudinal direction.

Then, when the ball cloth B is set on the needle plate 13 so as to overlap the cloth M, the binder 30 is placed from above, and both ends of the width direction of the ball cloth B (the left-right direction in FIG. 2). Is turned up from both ends in the width direction of the bottom plate portion 31, and further, both end portions in the width direction of the ball cloth B are respectively along the side surfaces on both sides of the standing plate portion 32 so as to be described later. , 21. In other words, the ball cloth B is placed from one side surface of the standing plate portion 32 to the other side surface 32 through the bottom plate portion 31. In this way, while setting the ball cloth B around the binder 30, while feeding the ball cloth B and the body cloth M, sewing is performed with the two needles 41, 41 on both sides of the standing plate portion 32 and the center knife. A straight cut S is formed by the vertical movement of 51.
Further, a guide member 33 is provided immediately in front of the cloth feeding direction F of the binder 30 so as not to be torn by the center knife 51. The guide member 33 is bifurcated in the same direction F so that the shape in plan view is substantially V-shaped. With this shape, both ends in the width direction of the ball cloth B are guided in a direction away from the upright plate portion 32 and are guided in a direction to avoid the center knife 51 when the cloth is fed.

(Large press feed mechanism)
The large presser feed mechanism 20 includes large pressers 21 and 21 that press the cloth M from above on both sides in the width direction of the ball cloth B set on the binder 30, and a support body 22 that supports the large pressers 21 and 21. An air cylinder (not shown) that moves the large pressers 21 and 21 up and down via the support 22 and the width direction both ends of the ball cloth B are bound to each other by being built in each large presser 21 and 21 and moving inward to each other. A folding plate (not shown) that is folded above the bottom plate portion 31 of 30 and a presser as feed driving means for moving the cloth B and body cloth M pressed by the large pressers 21 and 21 in the cloth feed direction F via the support 22. And a motor 23 (FIG. 10).
Each of the large pressers 21 and 21 is a rectangular flat plate, and each of the large pressers 21 and 21 is supported by the support body 22 in a state where the longitudinal direction is along the X-axis direction. The large pressers 21 and 21 are supported so that the flat plate surfaces thereof are parallel to the XY plane. Then, it can be switched to two upper and lower positions by driving the air cylinder. When the air cylinder is in the upper position, it is separated from the upper surface of the sewing machine table 11 and becomes the upper surface height of the sewing machine table 11 at the lower position. The two large pressers 21 and 21 are supported in a state of being separated from each other in the Y-axis direction so that at least the standing plate portion 32 of the binder 30 can pass between them.
The support 22 is supported on the sewing machine table 11 so as to be movable along the X-axis direction, and the two large pressers 21 and 21 to be supported pass outside the vertical movement path of the two needles 41 and 41. Is arranged. The support 22 is driven by a pressing motor 23 through a ball screw mechanism (not shown).

(Corner knife mechanism)
FIG. 6 is a perspective view of the corner knife mechanism 100, FIG. 7 is an enlarged perspective view showing an installed state of each corner knife 101 to 104, and FIG. 8 is an explanatory diagram showing a selection operation of the corner knife 101 to 104 that moves up and down. . In addition, in FIG. 6, each corner knife mechanism 100A, 100B mentioned later has shown the state which removed two of the four corner knife 101-104.
The corner knife mechanism 100 includes two corner knife mechanisms 100A and 100B that are provided individually at both ends of the straight cut S and that form a substantially V-shaped cut V, respectively.
The corner knife mechanisms 100 </ b> A and 100 </ b> B are both disposed below the sewing machine table 11, on the passage path of the large pressers 21 and 21 by the large presser feeding mechanism 20, and on the front side in the cloth feeding direction from the center knife 51. The veneer B and the body cloth M conveyed by the large press feed mechanism 20 are pierced by a pair of corner knives from below, so that a substantially V-shaped cut is formed at the positions corresponding to both ends of the straight cut S. Form.
Each corner knife mechanism 100A, 100B is arranged along the cloth feeding direction F, and the corner knife mechanism 100A is arranged behind the corner knife mechanism 100B. That is, one corner knife mechanism 100A forms a pair of diagonal cuts on the rear end side of the straight cut S, and the other corner knife mechanism 100B forms a pair of diagonal cuts on the front end side of the straight cut S. belongs to. Only the corner knife mechanism 100B is mounted on the table 11 so that it can be moved and positioned along the cloth feeding direction F by the unit moving motor 90 (see FIG. 10). Hereinafter, when the two corner knife mechanisms are described separately, the corner knife mechanism 100A may be referred to as a “fixed side” and the corner knife mechanism 100B may be referred to as a “moving side”.
Since the corner knife mechanism 100A and the corner knife mechanism 100B have substantially the same structure that is mirror-symmetric with respect to the YZ plane, the details are performed only for the corner knife mechanism 100B and the mirror-symmetric structure. The components of the corner knife mechanism 100A are denoted by the same reference numerals and description thereof is omitted.

  The corner knife mechanism 100B includes two types of corner knife 101, 102, 103, 104 on the left and right sides, and a corner knife holding body supported by a pair of round bar-shaped guide shafts 14 disposed on the lower surface side of the table 11. And a block-shaped structure that is supported so as to be movable along the Y-axis direction in a recess 105a formed on the rear side surface of the unit main body 105 and that holds the corner knives 101-104. The index knife is selected by the cooperation of the index moving mechanism 120 as a transverse feed mechanism having a function of selecting the index 106, and the index knife moving and positioning the index 106 along the Y-axis direction. And a vertical movement mechanism 130 to be moved.

  The unit main body 105 has a frame shape and is supported in a state where the pair of guide shafts 14 are inserted at one end in the Y-axis direction. Further, a concave portion 105a is formed on one side surface on the rear side of the unit main body 105, and an index 106 is disposed inside the concave portion 105a. Although the unit body 105 of the corner knife mechanism 100A is fixedly supported, the unit body 105 of the corner knife mechanism 100B is driven in the X-axis direction by driving the unit moving motor 90 via a belt feed mechanism or a ball screw mechanism (not shown). It can be positioned at any position. The unit moving motor 90 and a linear feed mechanism such as a belt feed mechanism or a ball screw mechanism constitute a longitudinal feed mechanism. Note that a linear motor may be employed as the unit moving motor 90.

  The index 106 is fixedly equipped with two upper and lower support rods 106a extending along the Y-axis direction from one side surface in the Y-axis direction, and these are inserted into insertion holes provided on the unit body 105 side. Thus, the index 106 is supported with respect to the unit main body 105 so as to be movable along the Y-axis direction.

Four corner knife mounting bases 107, 108, 109, and 110 are provided on the upper surface of the index 106, and each of the mounting bases 107 to 110 individually holds the corner knife 101 to 104. Each of the mounting bases 107 to 110 adjusts the angle of each corner knife 101 to 104 around the Z axis by loosening a fastening screw (not shown) (see FIG. 9A) and the inclination angle to which the tooth tip is directed. It can be adjusted manually (see FIG. 9B). For each corner knife 101-104, the inclination angle of the oblique cut with respect to the straight cut S is determined by adjusting the angle around the Z axis, and the cutting length of the oblique cut is determined by adjusting the inclination angle to which the tooth tip is directed.
Here, the example of adjustment of each corner knife 101-104 seen from upper direction is demonstrated based on FIG. 8 (B). The two right corner knives 101 and 102 are for forming oblique cuts formed on the right side with respect to the straight cut S, and each of them is inclined in a direction toward the right side toward the front. The corner knife 102 is inclined so that the cutting length of the oblique cut becomes longer. Further, the inclination angle around the Z-axis is adjusted so that the widths h1 and h2 in the Y-axis direction of the oblique cuts formed by the corner knives 101 and 102 are equal.
The two left corner knives 103 and 104 are for forming a diagonal cut formed on the left side with respect to the straight cut S, and each of them is inclined toward the left side toward the front. The corner knife 104 is inclined so that the cutting length of the oblique cut becomes longer. Further, as in the case of each corner knife 101, 102, the inclination angle around the Z axis is adjusted so that the widths h1 and h2 in the Y axis direction of the oblique cut formed by each corner knife 103, 104 are equal. Has been. That is, the corner knives 101 and 103 correspond to “short knives”, and the corner knives 102 and 104 correspond to “long knives”.

  Further, each mounting base 107 to 110 has a sliding shaft (not shown) along the Z-axis direction on the lower side thereof, and is supported so as to move up and down with respect to the index 106 by sliding of the shaft. ing. And the raising / lowering brackets 107a-110a which are the engagement protrusions which protruded ahead are formed in the lower end part of the said each sliding shaft. These lift brackets 107a to 110a protrude forward from the front surface of the index 106, and a vertical movement mechanism 130 described later moves the corner knives 101 to 104 up and down via the lift brackets 107a to 110a. It has become.

The index moving mechanism 120 is connected to an index motor 121 as a positioning motor fixedly mounted on the upper part of the unit main body 105, a screw shaft 122 that is rotationally driven by the index motor 121, and the screw shaft 122 via a ball screw. And a moving body 123.
The screw shaft 122 is rotatably supported on the upper surface of the unit main body 105 in a state along the Y-axis direction, and one end of the screw shaft 122 is coupled to the output shaft of the index motor 121 through a coupling.
The moving body 123 is held by an arm portion 106 b extending from one end portion of the index 106 in the Y-axis direction. Thus, when the screw shaft 122 is rotationally driven by the index motor 121, the moving body 123 receives a moving force in the longitudinal direction (Y-axis direction) of the screw shaft 122 by the action of the ball screw mechanism, and the index 106 moves in the Y-axis direction. Is done.
The movement of the index 106 in the Y-axis direction by the index moving mechanism 120 is used and selected when a pair of corner knives to be moved up and down by a vertical movement mechanism 130 described later is selected from the corner knives 101 to 104. It is also used when adjusting the position of the oblique cut by the corner knife in the Y-axis direction.

  The vertical movement mechanism 130 raises the corner knife to form a diagonal cut on the left side of the straight cut S and the first air cylinder 131 that raises the corner knife to form a diagonal cut on the right side of the straight cut S. A second air cylinder 132 and cylinder brackets 133 and 134 as engagement members provided on the output shafts of the air cylinders 131 and 132 and selectively engageable with the lifting brackets 107a to 110a described above are provided. Yes.

The air cylinders 131 and 132 are mounted on the unit main body 105 so that their operating directions are parallel to the Z-axis direction.
Each cylinder bracket 133, 134 is a drum-shaped member formed by reducing the diameter of only the middle part of the cylinder in the axial direction, and the output of each air cylinder 131, 132 with its center line oriented in the Z-axis direction. Equipped on the shaft. Then, when the index 106 moves along the Y-axis direction, each air cylinder 131 so that the tip end portions of the lifting brackets 107a to 110a pass between the portions where the diameters of the cylinder brackets 133 and 134 are reduced. 132 and cylinder brackets 133 and 134 are disposed in the unit main body 105.

That is, when the index 106 moves along the Y-axis direction, the lifting brackets 107a to 110a pass between the small-diameter portions of the cylinder brackets 133 and 134 in the arrangement order, and thus are the operation targets. By controlling the index motor 121 of the index moving mechanism 120 so that the lifting bracket of the corner knife stops between the small diameter portions of the cylinder bracket 133 or 134, the predetermined lifting bracket and the cylinder bracket are engaged with each other. Alternatively, the predetermined corner knife can be moved up and down by driving the second air cylinders 131 and 132.
On the lower surface of the unit main body 105, the index 106 is in a position where (1) the lifting bracket 107a of the corner knife 101 is engaged with the cylinder bracket 133, and the lifting bracket 109a of the corner knife 103 is engaged with the cylinder bracket 134. 3, when (2) the lifting bracket 108 a of 102 is in a position where it engages with the cylinder bracket 133, and (3) when the lifting bracket 110 a of the corner knife 104 is in a position where it engages with the cylinder bracket 134. An optical index sensor 111 (see FIG. 10) that detects the presence of two positions is provided, and positioning control of the index 106 is performed by such sensor detection. These states (1) to (3) are referred to as states where the corner knives 101 to 104 are in the operating positions.

  Note that the overlapping range of the cylinder brackets 133 and 134 and the lifting brackets 107a to 110a has some width in the Y-axis direction as shown in FIG. , 134, the engagement state can be maintained even if the elevating brackets 107a to 110a are somewhat moved in the Y-axis direction. And each corner knife 101-104 is moved to the Y-axis direction in the range which can maintain the said engagement state, and it is possible to adjust the position of a cutting position.

(Control system for hem stitch machine)
FIG. 10 is a block diagram showing a control system including the operation control means 80 of the edge stitch sewing machine 10.
The operation control means 80 includes input / output (not shown) of a display input means 85 for displaying predetermined characters or image information and inputting for making various settings, and a start switch 87 for inputting the start of sewing. It is connected through a circuit. Further, the operation control means 80 is connected to an encoder 88 for detecting the rotation speed of the sewing machine spindle motor 45 via an input circuit 88a, and can detect a rotation angle and a rotation speed from a predetermined origin. It has become.
Further, the operation control means 80 includes an electromagnetic valve 70 of the air cylinder 65 that switches between the operating state and the driving state of the sewing machine spindle motor 45, the presser motor 23, the knife motor 57, the unit moving motor 90, and the center knife that are the objects of the control. Are connected via drivers 45a, 23a, 57a, 90a and 70a, respectively.
In addition, an electromagnetic valve (not shown) that drives an air cylinder that moves the binder 30 up and down and an air cylinder that moves the large pressers 21 and 21 up and down is connected to the operation control means 80 via a driver. Similarly, the index motor 121 and the solenoid valves 135 and 136 of the first and second air cylinders 131 and 132 for raising and lowering the corner knife and the index sensor 111 described above are drivers 121a, 135a and 136a, and an input circuit 111a. Connected through.
Further, the operation control means 80 is connected with a solenoid valve 89 for driving a knife drive cylinder (not shown) for driving a knife for cutting a sewing thread and the needle switching solenoid 43 described above via drivers 89a and 43a. Yes.

  The operation control means 80 includes a CPU 81 for performing various processes and controls, a correction control program 82a for correcting the position of the corner knife in the Y-axis direction when forming a slanted cut for the edge stitch, and an operation control for the sewing machine for the edge stitch. A ROM 82 in which a sewing control program 82b to be executed is written, a RAM 83 as a work area for storing various data in the processing of the CPU 81, and an EEPROM 71 for recording sewing data and various setting data are provided.

(Setting parameters for operation control in the corner knife mechanism)
Here, setting parameters in the operation control of the corner knife mechanism 100 will be described.
In order to control the operation of the corner knife mechanism 100 for forming oblique cuts, as shown in FIGS. 2 and 3, the total length L of the left and right straight seams TR and the cloths of the front oblique cuts VFL and VFR are preliminarily provided. Lengths CFL and CFR in the feed direction, correction feed amounts HFL and HFR in the diagonal cuts VFL and VFR, lengths CRL and CRR in the fabric feed direction of the diagonal cuts VRL and VRR on the rear side, and in the diagonal cuts VRL and VRR Correction feed amount HRL, HRR, feed amount setting of fabrics B, M by large pressers 21, 21 for each stitch, and lengths DS, DL of the cloth knife feed direction of corner knife 101-104 in each corner knife mechanism 100A, 100B (See FIG. 8 (B)), the set feed amount of the large pressers 21 and 21 for each stitch, and the Y direction in the maximum movement position Km in the X axis direction (cloth feed direction) front side of the corner knife mechanism 100B. The resulting error Ko is set. These set values are set and input by the display input means 85 and stored in the EEPROM 71.

  Here, the maximum movement position Km and the error Ko as the movement point of the corner knife mechanism 100B will be described with reference to FIG. The unit main body 105 of the corner knife mechanism 100B has a maximum movement position Km that becomes a design limit position of the vertical feed mechanism from the position closest to the unit main body 105 of the corner knife mechanism 100A (the rearmost position) to the front. It is possible to move up to. The corner knife mechanism 100B can be slidable with respect to the guide shaft 14 provided in the unit main body 105, for example, depending on the processing accuracy and assembly accuracy of the parts, for example, the guide shaft 14 is not parallel to the X-axis direction. Due to factors such as the bent metal bearing being mounted, the error moves in the direction non-parallel to the X-axis direction (cloth feed direction), and as a result, the error that occurs in the Y-axis direction in proportion to the distance from the home position May become larger. Accordingly, the unit main body 105 of the corner knife mechanism 100B is moved in advance to the maximum movement position Km at which the error becomes maximum, and the operator manually measures the error Ko in the Y-axis direction, and the value is displayed and input means 85. Input the setting with. Thereby, the display input means 85 functions as an error input means. Further, the error Ko inputted by the setting input is stored in the EEPROM 71, whereby the EEPROM 71 functions as a storage means.

(Processing by correction control program)
Next, correction control in the formation of the oblique cut executed by the CPU 81 by the correction control program 82a will be described.
First, as one step of the operation control of the entire ball edge stitching, the CPU 81 executes the operation control of forming each oblique cut by each corner knife mechanism 100A, 100B. With this operation control, as shown in FIG. 12, first, the presser motor 23 is driven, and the sewing product (ballcloth B and body cloth M) is distanced Ps from the position where the center knife 51 cuts the straight cut S. Then, the rear end position RE of the straight line break S is positioned to the corner knife cutting position of the corner knife mechanism 100A. The feed distance Ps can be known in advance from the design arrangement dimensions of the center knife 51 and the corner knife mechanism 100A that are fixedly provided, and is prepared in the EEPROM 71 in advance.
Then, the unit moving motor 90 is controlled so that the corner knife mechanism 100B moves forward from the origin position by a distance Pc equal to the length of the straight cut S with respect to the corner knife mechanism 100A. The distance Pc is calculated from each parameter described above.
That is, Pc = L−CFR−HFR−CRR−VRR can be obtained, and the unit moving motor 90 is driven by a moving amount based on this.
Further, the CPU 81 refers to the setting parameters in the EEPROM 71, specifies the corner knife used for cutting from the lengths CFL, CFR, CRL, CRR in the cloth feed direction of the oblique cuts VFL, VFR, VRL, VRR, The index motor 121 of each corner knife mechanism 100A, 100B is driven to move the index 106 such that the corner knife lifting brackets 107a to 110a to be used and the cylinder brackets 133, 134 are in predetermined engagement positions.

The correction control performed based on the correction control program 82a is executed in the process of operation control for forming the oblique cut. That is, the CPU 81 reads the maximum movement position Km forward of the corner knife mechanism 100B in the X-axis direction (cloth feed direction) and the error Ko generated in the Y-axis direction from the EEPROM 71, and in the Y-axis direction with respect to the movement amount in the X-axis direction. Is calculated by Ko / Km and multiplied by the movement amount Pc of the corner knife mechanism 100B in the X-axis direction. Thereby, the error amount in the Y-axis direction caused by the positioning of the corner knife mechanism 100B is calculated as Pc · Ko / Km. Then, the position correction is performed by the calculated error amount from the state where the lifting brackets 107a to 110a of the corner knife mechanism 100B are engaged with the cylinder brackets 133 and 134 so that the center positions in the Y-axis direction coincide with each other. Then, the drive control of the index motor 121 is executed. When the corner knife 102 or 104 is used, the lift brackets are separately positioned with respect to the cylinder brackets 133 and 134, and the air cylinders 133 and 134 are driven separately. The position correction is executed for each individual operation of aligning the lifting bracket with respect to each cylinder bracket 133, 134.
The CPU 81 functions as correction control means by executing processing based on the correction control program 82a.

(Ball stitching operation control)
The operation control of the edge stitching will be described with reference to the flowcharts of FIGS. The process according to the flowcharts of FIGS. 13 to 16 is a process performed mainly by the CPU 81 executing the sewing control program 82b, and a part of the process of FIG. 16 is performed when the CPU 81 executes the correction control program 82a. Process.
FIG. 13 is a flowchart showing the overall flow of operation control of the bead stitching, FIG. 14 is a flowchart showing control of the set operation in the operation control of bead stitching, and FIG. 15 is a sewing operation (seam stitch) in the operation control of the bead stitching. And FIG. 16 is a flowchart showing the control of the stitching end operation (corner cut formation) of the edge stitch, and FIG. 17 is a flowchart showing the position correction control of the corner knife in the Y-axis direction. is there.

First, the overall flow of the sewing operation will be described with reference to FIG.
When the sewing is started, first, the setting operation processing of the body cloth M and the ball cloth B is performed (step S20), and then the formation operation control of the straight stitches TL and TR and the straight cut S is performed (step S50). Finally, corner cut forming operation control is performed as a sewing end operation process (step S70), and a series of edge stitches is completed. The processes in steps S20 to S70 are repeatedly executed, and the garment stitches of the body cloth and the ball cloth B are performed one by one.

Next, processing of the set operation in the sewing operation will be described with reference to FIG.
First, the presser motor 23 is driven to move the large presser 21 from the origin position to a predetermined sewing start position (step S21).
Next, a marking light (not shown) on the upper surface of the table 11 is irradiated, and the irradiation position indicates, for example, a sewing start position (there is a sewing end position or a position just between the sewing start and sewing end). The body cloth M is set so that the sewing start scheduled position of the body cloth M is aligned with the irradiation position, and when the ball cloth B is set on the large presser 21, the large presser 21 is lowered, and the cloth M Is held by the large presser 21 (step S22). Further, the binder 30 is lowered between the large pressers 21 and 21 (step S23). At this time, the corner knife mechanism 100B moves to a predetermined origin position and stands by (step S24).
Further, each large presser 21 is provided with a folding plate for folding both sides of the ball cloth B to the upper surface side of the binder 30, which is moved inward by the drive of the air cylinder, and the ball cloth B is moved to the binder 30. (Step S25).
Further, when the flap cloth is sewn on the upper surface of the ball cloth T, the flap cloth is set, and then the cloth pressing mechanism is operated so as to press the flap cloth (step S26).
Thereby, the set operation is completed. Note that the sewing of the flap cloth is not essential and may not be performed.

Next, the control of the sewing operation will be described with reference to FIG.
By driving the presser motor 23, the large presser 21 starts to move from the origin position to the sewing start position, and the position that is the front end of the straight stitch TR or TL in the fabrics M and B is conveyed below the sewing needle 41 ( Step S51). This transport distance coincides with the distance from the marking light irradiation position to the sewing needle 41 described above. That is, the conveyance to the sewing start position is performed on the assumption that the sewing start planned position of the sewing product is aligned with the irradiation position of the marking light.
Then, the sewing machine spindle motor 45 starts driving, and the formation of the seam is started (step S52). For example, in the example of FIG. 3, when the straight stitch TR is first formed with the right needle and the fabrics M and B are conveyed by the end position deviation CF, the stitches are switched to both needles and the straight stitch TL is changed. Formation is also started. If the set end position deviation CF is 0, as shown in FIG. 2, the two needles 41 start sewing simultaneously, and if the end position deviation CF is a negative value, Contrary to 3, sewing starts from the left needle.

When sewing is started, the number of stitches is counted from the start of driving of the sewing machine spindle motor 45, and it is determined whether the number of stitches until the sewing is completed is reached (step S53). If the number of stitches has reached the completion number, the sewing is finished.
If not, the pressing motor 45 is driven according to the set feed amount of the large pressings 21 and 21 for each stitch (step S54). The number of stitches completed is calculated by dividing the preset total length L of the straight stitch TR by the set feed amount of the large pressers 21 and 21 for each stitch.

Next, it is determined from the accumulated rotation amount of the presser motor 45 whether or not the center knife lowering position (front end FE of the straight line break S) determined based on the end position reference of the stitch end has been reached (step S55). In this case, the lowering and vertical movement of the center knife 51 is started, and the formation of the straight line break S is started (step S56). The distance from the start of sewing to the lowering start position of the center knife is the positional relationship between the length CFR of the front diagonal cut VFR in the cloth feed direction and the correction feed amount HFR at the diagonal cut VFR, the sewing needle 41, and the center knife 51. The arrival of the lowered position of the center knife 51 is determined depending on whether or not conveyance has been performed for the distance from the start of sewing.
If it is determined in step S55 that the center knife has not yet reached the lowering position of the center knife, the process proceeds to step S57. The process is returned to step S53.

On the other hand, if it is determined in step S55 that the straight cut line S has already been formed past the lowered position of the center knife 51, the process proceeds to step S57.
Next, it is determined from the accumulated rotation amount of the presser motor 45 whether or not the ascending position of the center knife 51 (the rear end portion of the straight line break S) determined based on the end position reference of the stitch end portion has been reached (step S57). In the case where the center knife 51 is moved upward and downward, the straight cut S is finished (step S58). The raised position of the center knife is a position conveyed from the lowered position of the center knife by a distance obtained by subtracting the length of the straight cut by the length of the blade of the center knife 51 in the X-axis direction.
Thereafter, the process is returned to step S53, and it is determined whether or not the rear end position of each straight stitch TL, TR has been reached. And when it reaches | attains, the formation operation | movement of the straight seams TL and TR and the straight cut S is complete | finished.

Next, the control of the sewing end operation in the sewing operation will be described with reference to FIG.
As the forming operation of the straight stitches TL and TR and the straight cut S is completed, the workpiece is transported to the forming position of the diagonal cut by the corner knife mechanism 100 (step S71).
Next, the opening amount (distance Pc in FIG. 12) of the corner knife mechanism 100B with respect to the corner knife mechanism 100A is calculated (step S72).
Next, the corner knife mechanism 100B is moved to the target position by driving the unit moving motor 90 based on the calculated opening amount (step S73).
Further, the CPU 81 calculates an error amount (Pc · Ko //) generated in the Y-axis direction at the target position of the corner knife mechanism 100B from the calculated opening amount and the ratio of the error in the Y-axis direction to the movement amount in the X-axis direction. Km) is calculated (step S74).

Then, the corner knife to be used is identified with reference to the setting parameter, and the elevation bracket of the corner knife used by the index 106 and the cylinder bracket 133 or 134 coincide with each other for each of the corner knife mechanisms 100A and 100B. Thus, the operation control of the index motor 121 is executed (step S75).
At this time, only the corner knife mechanism 100B is corrected by the aforementioned correction amount to position the index 106 (step S76).
And about each corner knife mechanism 100A and 100B, the 1st and 2nd air cylinders 131 and 132 are driven, a corner knife is pushed up, and diagonal cut is formed (step S77). At this time, depending on the selection of the corner knife, the air cylinders 131 and 132 may not be simultaneously performed. In this case, after the first air cylinder 131 is driven, the lifting bracket of the other corner knife is used. Is positioned on the cylinder bracket 134 to drive the air cylinder 132. At this time, the corner knife mechanism 100B executes position correction in the Y-axis direction when the index 106 is aligned.
When the formation of all the oblique cuts is completed, the unit movement 90 is driven so as to return the corner knife mechanism 100B to the origin position, and the sewing end operation is completed (step S78).

(Effect of embodiment)
In the edge stitch sewing machine 10, when the CPU 81 executes processing based on the correction control program 82a, the moving direction of the unit body 105 of the corner knife mechanism 100B is not parallel to the cloth feeding direction due to assembly accuracy, component accuracy, and the like. Even if an error occurs in the Y-axis direction due to the movement of the unit body 105, the unit body 105 can be moved to any position if the error amount Ko is measured once at the maximum movement position Km of the unit body 105. An error amount generated in the Y-axis direction can be obtained, and correction can be performed based on this.
Therefore, it is possible to improve the sewing quality by optimizing the formation position of the diagonal cuts by the corner knives 101 to 104 without performing complicated work.
Further, since the error in the Y-axis direction is corrected by the index motor 121 for selecting the corner knife, a mechanism structure for newly performing correction is not necessary, and the implementation cost can be greatly reduced.
Further, in the edge stitch sewing machine 10, the EEPROM 71 stores the distance to the maximum movement position of the unit body 105 of the corner knife mechanism 100B, and the CPU 81 executes processing based on the correction control program 82a, whereby the maximum movement is performed. Since the error ratio at the position is calculated, when calculating the movement ratio of the unit body 105 of the corner knife mechanism 100B and the error ratio generated in the orthogonal direction, the error ratio is calculated by calculating the maximum movement distance and the maximum error caused thereby. Therefore, a more accurate value can be obtained, and the position of the corner knife can be corrected more accurately.

(Other)
In the above-described bead stitch sewing machine 10, the error ratio is calculated by inputting the error amount Ko at the maximum movement position Km of the unit main body 105 of the corner knife mechanism 100B, but the movement range is not limited to the maximum movement position. May be a known position. However, in that case, it is necessary to determine a known position in advance and register it in the EEPROM 71 as a storage means.
Further, the moving point of the unit main body 105 for measuring the error may be arbitrarily set from the display input unit 85 as the setting unit. In that case, the error ratio is calculated by dividing the Y-axis direction error measured at the moving point by the set numerical value of the moving point.

Further, in the above-described bead stitch sewing machine 10, the movement point for measuring the error in the Y-axis direction is only one point of the maximum movement position of the unit main body 105, but two movement points are set, and the Y-axis at each movement point is set. A ratio between the moving distance of the unit main body 105 and the position error of the corner knife in the Y-axis direction may be obtained based on the direction error. In that case, for example, even when the unit main body 105 of the corner knife mechanism 100B has already generated an error in the Y-axis direction from the origin position, the error ratio can be calculated by eliminating the influence, and a more accurate value can be obtained. Therefore, the position of the corner knife can be corrected with higher accuracy.
Needless to say, when two movement points are set, one movement point may be set as the maximum movement position.

  Further, although the corner knife mechanism 100A on the rear side in the cloth feeding direction is a fixed type, the present invention is not limited to this, and a longitudinal feeding mechanism may be provided so as to be movable back and forth similarly to the corner knife mechanism 100B. . In that case, it is desirable that the corner knife mechanism 100A performs error correction in the same manner as the corner knife mechanism 100B.

It is a perspective view which shows the schematic structure of the whole edge stitch sewing machine. It is explanatory drawing which shows the arrangement | positioning relationship of the linear cut by the center knife, the cut by a corner knife, and the stitch by a two needle | hook in the bead stitch which forms a rectangular pocket opening part. It is explanatory drawing which shows the arrangement | positioning relationship of the linear cut by the center knife, the cut by a corner knife, and the stitch by a two needle | hook in the bead stitch which forms a diagonal pocket opening part. It is a perspective view of a needle up-and-down movement mechanism. It is a perspective view which shows the cutting | disconnection state of a needle | hook up-and-down moving mechanism and a center knife mechanism. It is a perspective view of each corner knife mechanism. It is an expansion perspective view which shows the installation state of each corner knife. 8A is an explanatory view showing the selection operation of the corner knife that moves up and down, FIG. 8B is an explanatory view showing an adjustment example of each corner knife, and FIG. 8C is the relationship of the lifting bracket with respect to the cylinder bracket. It is explanatory drawing which shows a combined state. FIG. 9A shows an angle adjustment state of each corner knife around the Z axis, and FIG. 9B is an explanatory diagram showing a cutting length adjustment state. It is a block diagram which shows the control system containing the operation control means of a bead stitch sewing machine. It is explanatory drawing which shows the relationship between the error which arises in the unit main body of a corner knife mechanism, and movement amount. It is explanatory drawing which shows the moving distance of a to-be-sewn material and a unit main body in sewing end operation | movement (corner cut formation). It is a flowchart which shows the whole flow of operation | movement control of a bead stitch. It is a flowchart which shows control of the setting operation | movement in the operation control of a bead stitch. It is a flowchart which shows control of the sewing operation | movement (stitch and linear cut formation operation | movement) in the operation control of a bead stitch. It is a flowchart which shows control of the sewing end operation | movement (corner cut formation) of a bead stitch.

Explanation of symbols

10 Sewing machine 14 Guide shaft 20 Large presser feed mechanism (cloth feed mechanism)
21 Large presser 23 Presser motor 40 Needle vertical movement mechanism 41 Sewing needle 42 Needle bar 45 Sewing spindle motor 50 Center knife mechanism (moving knife mechanism)
51 Center knife 57 Female motor 71 EEPROM (storage means)
80 Operation control means 81 CPU
82a Correction control program 82b Sewing control program 82 ROM
83 RAM
85 Display input means (error input means)
90 Unit moving motor (vertical feed mechanism)
100, 100A, 100B Corner knife mechanism 101-104 Corner knife 105 Unit body (corner knife holder)
120 Index movement mechanism (transverse feed mechanism)
121 Index motor B Ball cloth F Cloth feed direction Km Maximum movement position (movement point)
Ko Error in the Y-axis direction (error in the direction perpendicular to the cloth feed direction)
M Body cloth S Straight cut TL, TR Straight stitch V V-shaped cut VFL, VFR, VRL, VRR Diagonal cut

Claims (4)

A cloth feed mechanism that holds and conveys the fabric and the ball cloth;
A needle up-and-down movement mechanism that moves up and down two sewing needles that form two straight stitches parallel to the cloth feed direction and the cloth feed direction;
A moving knife mechanism that forms a straight cut along the cloth feed direction between the two straight stitches;
In a hem stitch sewing machine provided with a corner knife mechanism that forms an oblique cut between the end of the two straight stitches and the end of the straight cut,
The corner knife mechanism is
Two corner knife holders for forming oblique cuts individually at one end and the other end of the straight cut,
A longitudinal feed mechanism that moves one corner knife holding body along the cloth feed direction according to the length of the straight cut;
A transverse feed mechanism that is provided for each of the corner knife holders and that selects a corner knife to be used by moving a plurality of corner knife forming a plurality of types of oblique cuts in a direction perpendicular to the straight cut; ,
For the corner knife holder that performs the movement, an error input means for inputting an error of the corner knife position that occurs in a direction orthogonal to the straight cut at a moving point that is a predetermined distance away from the origin position;
Storage means for storing a predetermined distance from the origin to the moving point;
For the cutting operation by the corner knife held by the corner knife holding body that performs the movement, the cutting execution position of the corner knife holding body is determined from the relationship between the input error and the distance from the origin position to the moving point. And a correction control means for correcting the position by the lateral feed mechanism and forming a diagonal cut.   2. The edge stitch sewing machine according to claim 1, further comprising setting means for setting and inputting a distance from the origin position to the moving point.   2. The edge stitch sewing machine according to claim 1, wherein the storage means stores a distance from the origin to a maximum movement position of the corner knife holder as a distance from the origin to the moving point. The error input means can input an error at two moving points,
For the cutting operation by the corner knife held by the corner knife holding body that moves along the cloth feeding direction, the correction control means calculates the distance between the origin point and the error at each movement point. The bead according to claim 1, 2 or 3, wherein an error amount generated at a cutting execution position of the corner knife holding body is obtained from the relationship, and the oblique feed is formed by correcting the position by the lateral feed mechanism. Sewing machine.

Images