CN113046931A

CN113046931A - Zigzag sewing machine

Info

Publication number: CN113046931A
Application number: CN202011537947.8A
Authority: CN
Inventors: 大桥隆弘
Original assignee: Juki Corp
Current assignee: Juki Corp
Priority date: 2019-12-26
Filing date: 2020-12-23
Publication date: 2021-06-29
Anticipated expiration: 2040-12-23
Also published as: JP2021104096A; CN113046931B; JP7441646B2

Abstract

The invention provides a zigzag sewing machine, which can more accurately detect the positions of the end edges of two sewed objects, and comprises: a lateral feeding mechanism which moves each sewed object along the needle swing direction of the sewing needle at the upstream side of the feeding direction of the sewed object than the needle drop position; a position detecting part for detecting the position of the needle swing direction of the end edge parts of two sewed objects respectively arranged on the conveying surface at the upstream side of the feeding direction in the needle swing direction; a control device for controlling the lateral feeding mechanism based on the detection of the position detection unit so that the end edge portions approach or abut against each other, the position detection unit including: a light source for irradiating a linear detection light along a needle swing direction so as to cross two sewed articles; the zigzag sewing machine is provided with a step forming part for forming a step between one of the objects to be sewn and the other of the objects to be sewn at a position of the conveying surface where the detection light is irradiated.

Description

Zigzag sewing machine

Technical Field

The present invention relates to a zigzag sewing machine which performs sewing for joining a sewn article to a sewn article.

Background

In order to join the end edge portion of the material to be sewn to the end edge portion of the material to be sewn, sewing is performed by a zigzag sewing machine which performs left and right needle swinging with respect to the advancing direction of sewing.

In conventional sewing, for example, when the end edge portion of one of the objects to be sewn and the end edge portion of the other object to be sewn do not have the same shape, an operator manually brings the end edge portions into abutment with the end edge portions and conveys the objects to be sewn to the needle drop position (see, for example, patent documents 1 and 2).

Patent document 1: japanese examined patent publication No. 55-48838

Patent document 2: japanese patent laid-open publication No. 2003-38877

However, since the operation of conveying the end edge portions of the respective materials to be sewn to the needle drop position after abutting each other requires skilled skill, there is a possibility that sewing quality greatly varies depending on the operator.

Disclosure of Invention

The invention aims to stably and highly maintain sewing quality.

The invention described in claim 1 provides a zigzag sewing machine for joining and sewing two objects to be sewn with end edge portions of the two objects to be sewn butted against each other, the zigzag sewing machine comprising:

a lateral feeding mechanism which moves the two sewed objects along the needle swing direction of the sewing needle at the upstream side of the needle falling position in the feeding direction of the sewed objects;

a position detecting unit that detects a position in the needle swing direction of each of two end edge portions of the workpiece to be sewn, which are respectively arranged on a conveying surface on an upstream side in the feed direction of the workpiece relative to the lateral feed mechanism, in one and the other of the needle swing directions; and

a control device for controlling the transverse feeding mechanism based on the detection of the position detection part so as to enable the end edge parts of the two sewed objects to approach or abut against each other,

the position detection unit includes: a light source that irradiates linear detection light along the needle swing direction so as to straddle the end edge portions of the two sewn objects; and an imaging unit for imaging the detection light irradiated to the two sewed articles from a direction different from the irradiation direction of the light source,

the zigzag sewing machine includes a step forming portion that forms a step between the end edge portion of one of the objects to be sewn and the end edge portion of the other object to be sewn at an irradiation position of the detection light on the conveying surface.

The invention described in claim 2 is the zigzag sewing machine described in claim 1, wherein both the irradiation direction of the detection light from the light source and the direction of the line of sight of the imaging unit are in either direction on a plane perpendicular to the conveying surface and parallel to the feed direction of the material to be sewn.

The invention described in claim 3 is the zigzag sewing machine described in claim 1 or 2, wherein an irradiation direction of the detection light from the light source is a normal direction with respect to the conveyance surface.

The invention described in claim 4 is the zigzag sewing machine described in any one of claims 1 to 3, wherein the light source is a laser light source.

An invention described in claim 5 is the zigzag sewing machine described in any one of claims 1 to 4, wherein the control device determines whether or not a gap is formed between the end edge portion of one of the objects to be sewn and the end edge portion of the other of the objects to be sewn, moves the two objects to be sewn to form a gap in the absence of the gap, and controls the traverse mechanism so that the end edge portions of the objects to be sewn approach or abut each other.

As described above, according to the present invention, since the lateral feed mechanism controlled based on the detection result of the position detecting unit is provided, the sewing quality can be stably and highly maintained regardless of the skill of the operator.

Further, according to the present invention, since the linear detection light is irradiated to the end edge portions of the objects to be sewn in a state of being cut off along the transport direction of the objects to be sewn by the step forming portion, even when no gap is generated between the end edge portions of the objects to be sewn, the position of the end edge portions in the needle swing direction can be appropriately detected, the position of the end edge portions of the objects to be sewn in the needle swing direction can be more appropriately adjusted, and the sewing quality can be improved.

Drawings

Fig. 1 is a side view showing a configuration of a main part of a zigzag sewing machine according to the present embodiment.

Fig. 2 is a plan view showing a configuration of a main part of the zigzag sewing machine.

Fig. 3 is a block diagram showing a control system of the zigzag sewing machine.

Fig. 4 is a plan view showing an example of two sewn articles.

Fig. 5 is a plan view showing an example of a stitch of the zigzag seam.

Fig. 6 is a cross-sectional view showing the configuration of the 1 st and 2 nd traverse mechanisms.

Fig. 7 is an explanatory view of an example of a captured image obtained by capturing, with a camera, detection light that is irradiated so as to straddle the end edge portions of each sewn article that has a step formed by the step forming portion.

Fig. 8 is a flowchart showing the edge position adjustment control.

Fig. 9 is a flowchart showing another example of the edge position adjustment control.

Fig. 10A is a plan view showing another example of the step forming portion, and fig. 10B is a side view.

Fig. 11 is a side view showing another example of the step forming portion.

Description of reference numerals:

10: a zigzag sewing machine; 11: sewing a needle; 12: a sewing machine motor; 13: a needle swing motor; 30: a transverse feeding mechanism; 30A: the 1 st transverse feeding mechanism; 30B: 2 nd infeed mechanism 38: a infeed motor; 40: a position detection unit; 41: a light source; 42: a camera (imaging unit); 43: an image processing device; 90: a control device; 91: a CPU; c1, C2: a sewed object; c11, C21: an end edge portion; f: a needle falling position; h: a conveying surface; h1: a step forming section; h11, H12: an inclined portion; k: a baseline; l: detecting light; l1, L2: intercepting the light; n: a gap; s: and (4) offsetting.

Detailed Description

Embodiments of the present invention will be explained. Fig. 1 is a side view showing a configuration of a main part of a zigzag sewing machine 10 according to the present embodiment, fig. 2 is a plan view showing the zigzag sewing machine 10, and fig. 3 is a block diagram showing a control system of the zigzag sewing machine 10.

In the zigzag sewing machine 10 (hereinafter, simply referred to as the sewing machine 10), the feed direction of the materials to be sewn C1 and C2 is horizontal in a state of being placed on a horizontal plane. In the following description, the feed direction of the sewn materials C1 and C2 is defined as the X-axis direction, the horizontal direction orthogonal to the X-axis direction is defined as the Y-axis direction, and the vertical up-down direction is defined as the Z-axis direction.

Further, in the X-axis direction, the downstream side in the feeding direction of the objects to be sewn C1 and C2 is "front" and the upstream side is "rear", in the Y-axis direction, in a state facing forward, the left-hand side is "left" and the right-hand side is "right", and one in the Z-axis direction is "up" and the other is "down".

The sewing machine 10 is a sewing machine suitable for butt-jointing and sewing the end edge portions C11 and C21 of the two objects to be sewn C1 and C2.

Fig. 4 is a plan view showing an example of the sewn article C1 and the sewn article C2. Here, both the sewn objects C1 and C2 are sheet-like materials having flexibility and being thicker than the difference in height between the sewn objects C1 and C2 formed by the height difference forming portion H1 described later. Further, this is an example, and joining and sewing of sheet materials of thin other materials may be performed.

The shape of the end edge portion C11 of the object to be sewn C1 to be joined at one end in the Y axis direction is different from the shape of the end edge portion C21 of the object to be sewn C2 at the other end in the Y axis direction, and the end edge portion C11 and the end edge portion C21 are joined by joining sewing, whereby the objects to be sewn C1 and C2 are curved in shape, and the finished product after sewing is three-dimensional in shape.

In the sewing machines 10, the end edge portions C11 and C21 are butted against each other without forming a gap therebetween and fed to the needle drop position, and the joint sewing is performed by zigzag sewing in which stitches are made to cross both the end edge portions C11 and C21, with respect to the objects C1 and C2 to be sewn.

Fig. 5 is a plan view showing an example of a seam of a zigzag seam. As shown in the drawing, the stitches of the zigzag seam are alternately diagonally left and right in the X-axis direction and are formed in a zigzag shape, and the stitches diagonally left and right are connected in a state where the end edge portions C11 and C21 are closely attached to each other by crossing the end edge portions C11 and C21 which are butted together.

In addition, fig. 5 illustrates a stitch in which the so-called four-point zigzag seam in which the needle is dropped is alternately performed for every three needles in the end edge portions C11 and C21, but a stitch in which the so-called two-point zigzag seam in which the needle is dropped is alternately performed for every three needles in the end edge portions C11 and C21 may be formed.

Brief structure of zigzag sewing machine

As shown in fig. 1 to 3, the zigzag sewing machine 10 includes: a needle up-and-down moving mechanism for moving the sewing needle 11 up and down at the needle falling position F; a needle swing mechanism for swinging the needle of the sewing needle 11 along the Y-axis direction; a feed mechanism for feeding the sewed fabric C1, C2 at a needle drop position of the sewing needle 11 by a predetermined feed pitch through the feed teeth 21; a kettle mechanism for winding the lower thread on the upper thread passing through the sewing needle 11 at the lower side of the feeding tooth 21; a traverse mechanism 30 for applying a moving motion in the Y-axis direction to the objects to be sewn C1 and C2 arranged in line along the Y-axis direction, respectively, at the rear side (upstream side in the feeding direction) of the needle drop position F; a position detecting unit 40 that detects positions in the Y axis direction of end edge portions C11 and C21 of two objects to be sewn C1 and C2 respectively arranged in one and the other of the needle swing directions, at the rear side (upstream side in the feeding direction) of the traverse mechanism 30; a sewing machine frame for receiving or supporting the above components; and a control device 90 for controlling the above-described respective configurations.

The needle up-down moving mechanism is a known structure in which a needle bar holding a needle 11 is moved up and down by a crank mechanism using a sewing machine motor 12 as a drive source.

The needle swing mechanism is a known structure in which a needle bar table supporting a needle bar so as to be movable up and down is arbitrarily moved in the Y-axis direction by using a needle swing motor 13 as a drive source.

The feed mechanism is a known structure including feed dog 21 and a power transmission mechanism, wherein the feed dog 21 can be inserted into and removed from a left and right opening formed in a needle plate, not shown, attached to the upper surface of a sewing machine body of the sewing machine frame, and the power transmission mechanism obtains power from a sewing machine motor 12 and applies an oblong motion along an X-Z plane to the feed dog 21. When moving in the upper part of the orbit of the oblong motion, the feed dog 21 protrudes upward from the opening of the needle plate, and can convey the objects to be sewn C1, C2 in the moving direction. In addition, the feed mechanism can arbitrarily adjust the feed amount (feed pitch) at one time by the feed adjustment motor 14.

Further, a presser foot 23 for pressing the objects to be sewn C1, C2 by a constant spring pressure is provided above the advancing and retreating position of the feed dog 21 in the needle plate.

The pot mechanism is a known structure including an outer pot which captures an upper thread by rotating a thread loop, an inner pot which houses a bobbin around which the lower thread is wound, and a power transmission mechanism which obtains power from a sewing machine motor 12 and applies a rotational force to the outer pot.

The zigzag sewing machine 10 is configured to: the upper surface of the sewing machine body of the sewing machine frame, not shown, is a conveyance surface H of each of the objects to be sewn C1 and C2. The transport plane H is parallel to the X-Y plane and is coplanar with the upper surface of a needle board, not shown. In the following description, the transport surface H is defined as including the upper surface of the needle plate.

At a position directly below the needle bar on the conveying surface H, a needle drop position F is formed as a long circular needle hole corresponding to the maximum allowable needle swing width. The long side direction of the pinhole is parallel to the Y-axis direction.

The needle swing mechanism swings the needle at the same width in the left-right direction around the midpoint of the needle hole in the Y-axis direction, which is the needle drop position F. A straight line along the X-axis direction passing through the middle point of the needle hole is set as a base line K of the needle swing.

In the sewing, one sewn object C1 is disposed on the left side of the base line K and the other sewn object C2 is disposed on the right side of the base line K on the conveyance plane H.

[ lateral feed mechanism ]

The traverse mechanism 30 performs a moving operation along the Y-axis direction of each of the objects to be sewn C1 and C2 so that the end edge portion C11 of the object to be sewn C1 is brought into proximity with or brought into contact with the end edge portion C21 of the object to be sewn C2 on the base line K.

The transverse feed mechanism 30 includes: a 1 st traverse mechanism 30A disposed on the left side of the base line K and moving the workpiece C1 in the Y-axis direction from above; and a 2 nd traverse mechanism 30B disposed on the right side of the base line K and configured to move the workpiece C2 in the Y-axis direction from above.

Fig. 6 is a cross-sectional view showing the configuration of the 1 st infeed mechanism 30A and the 2 nd infeed mechanism 30B. Since the 1 st and 2

nd traverse mechanisms

30A and 30B have the same structure and the same configuration, the same reference numerals are given to the configuration and redundant description thereof is omitted.

The 1 st and 2

nd traverse mechanisms

30A and 30B include: a roller 31 for conveying the sewn object C1 or C2 in the tangential direction of the outer periphery; a plurality of rollers 32 arranged at regular intervals along the outer circumference of the roller 31; a rotating shaft 33 to which the roller 31 is fixedly fitted; a support frame 34 rotatably supporting the rotary shaft 33; a pair of

sprockets

35, 36 and a timing belt 37 for transmitting torque from a drive source to the rotary shaft 33; and an infeed motor 38 as a driving source.

The rollers 32 are provided at regular intervals on the outer periphery of the roller 31, are rotatable about axes along the tangential direction at the respective mounting positions, and allow the sewn object C1 or C2, which is brought into contact with the outer periphery of the roller 31 and conveyed in the tangential direction, to move relative to the roller 31 in a direction along the rotation axis 33 or in a direction slightly inclined relative to the rotation axis 33.

In addition, strictly speaking, the roller 31 is in contact with the object to be sewn C1 or C2 via the rollers 32, but for simplification of explanation, the object to be sewn C1 or C2 is referred to as "in contact with the outer periphery of the roller 31" or "in contact with the roller 31".

[ position detecting part ]

As shown in fig. 1, the position detection unit 40 includes: a light source 41 that irradiates a linear detection light L along the Y-axis direction across the base line K on the conveyance surface H behind (upstream side in the feeding direction) the traverse mechanism 30; and a camera 42 as an imaging unit that images the detection light L from a direction different from the irradiation direction of the light source 41.

Specifically, the light source 41 is configured by a laser light source of single wavelength light, and the camera 42 has a filter suitable for capturing the single wavelength light of the light source 41.

The light source 41 irradiates the detection light L downward in the Z-axis direction. In contrast, the camera 42 is attached to the sewing machine 10 as follows: the irradiation position of the detection light on the transport plane H is imaged as the center of the imaging range with a line of sight parallel to the X-Z plane and inclined in a direction obliquely forward and downward.

On the other hand, as shown in fig. 2, a step forming portion H1 for forming a step between one sewn object C1 and the other sewn object C2 is provided in the vicinity of the irradiation position of the detection light L on the conveyance surface H.

The step forming portion H1 is formed by a rectangular protruding portion provided on one side (right side) in the Y-axis direction on the conveyance plane H with the base line K as a boundary, so as to be higher than the conveyance plane H. The upper surface of the level difference forming portion H1 is smooth along the X-Y plane, and the width in the X-axis direction is set sufficiently wider than the detection light L. Thus, the right half of the detection light L is irradiated to the upper surface of the level difference forming portion H1 in a state where the sewing materials C1 and C2 are not present.

Since the step forming portion H1 is only required to be able to provide a step between one sewn article C1 and the other sewn article C2, it may be separated from the base line K to some extent or may not be rectangular in shape.

Fig. 7 is a captured image of the detection light L emitted by the camera 42 so as to straddle the end edge portions C11 and C21 of the sewn object C1 and the sewn object C2 provided with the step by the step forming portion H1.

The camera 42 includes an image sensor such as a CCD (Charge-Coupled Device) or a cmos (complementary Metal Oxide semiconductor), and is capable of converting a captured image into image data, and the image data is input to the image processing Device 43 (see fig. 3).

Then, the processing result of the image processing device 43 is inputted to the control device 90, and the shift amounts of the end edge portions C11 and C21 in the Y axis direction with respect to the base line K are obtained from the positions of the respective portions of the detection light L within the imaging range, and the position adjustment amounts of the 1 st and 2

nd traverse mechanisms

30A and 30B in the Y axis direction with respect to the objects to be sewn C1 and C2 are determined.

Since the end edge portions C11 and C21 of the objects to be sewn C1 and C2 need to be conveyed to the needle drop position F at positions that coincide with the base line K in the Y axis direction, the positions of the end edge portions C11 and C21 in the Y axis direction need to be accurately detected.

Therefore, when the portion of the detection light L on the side of the workpiece C1 is the cutoff light L1 and the portion on the side of the workpiece C2 is the cutoff light L2, the position of the right end portion of the cutoff light L1 in the Y axis direction is determined from the captured image, and the amount of displacement of the edge portion C11 of the workpiece C1 from the base line K can be detected. Similarly, the position of the left end of the cutoff light L2 in the Y axis direction is determined from the captured image, and the amount of displacement of the end edge portion C21 of the object C2 from the base line K can be detected.

In addition, in the case where there is a gap N in the Y axis direction between the object to be sewn C1 and the object to be sewn C2, the detection light L is directly irradiated to the upper surface of the conveying surface H at the gap N to generate reflected light, but the reflected light directly reflected by the cut lights L1 and L2 and the upper surface of the conveying surface H can be easily recognized by applying low-reflectivity coating or the like to the upper surface of the conveying surface H, for example.

However, when the conveyance surface H is assumed to be free of the step forming portion H1, and when the gap N is generated between the edge portions C11 and C21 of the objects to be sewn C1 and C2 on the conveyance surface H, the cut light L1 on the object to be sewn C1 side and the cut light L2 on the object to be sewn C2 side are separated in the Y axis direction, and therefore the right end portion of the cut light L1 and the left end portion of the cut light L2 can be clearly extracted from the captured image, and the positions in the Y axis direction can be accurately detected.

However, when the gap N is not generated between the edge portions C11 and C21, the right end portion of the cutoff light L1 and the left end portion of the cutoff light L2 are joined to form a linear light on a straight line, and therefore, it is difficult to extract the right end portion of the cutoff light L1 and the left end portion of the cutoff light L2, and it is difficult to accurately detect the positions of the right end portion of the cutoff light L1 and the left end portion of the cutoff light L2 in the Y-axis direction.

In order to solve such a problem, since the height difference forming portion H1 is provided at the irradiation position of the detection light L on the conveyance surface H and the height difference forming portion H1 forms a height difference between the object to be sewn C1 and the object to be sewn C2, when the camera 42 performs imaging from an oblique direction, the offset S in the X axis direction is inevitably formed between the cutoff light L1 and the cutoff light L2 regardless of the gap N between the edge portions C11 and C21. Therefore, the right end portion of the cutoff light L1 and the left end portion of the cutoff light L2 can be clearly extracted from the captured image, and the positions in the Y axis direction can be detected more reliably and more accurately.

[ control device ]

As shown in fig. 3, the sewing machine 10 includes a control device 90 that controls the entire sewing machine at the time of sewing.

The sewing machine motor 12 of the needle vertical movement mechanism, the needle swing motor 13 of the needle swing mechanism, the feed adjustment motor 14 of the feed mechanism, and the infeed motors 38 of the 1 st infeed mechanism 30A and the 2 nd infeed mechanism 30B described above are connected to the controller 90 via the

drive circuits

12a, 13a, 14a, and 38a, respectively.

An encoder 15 for detecting the shaft angle is provided on a main shaft of the sewing machine, not shown, which is rotationally driven by the sewing machine motor 12, and the detected shaft angle is output to the control device 90 via an interface 15 a. The number of rotations and the rotation angle of the spindle can be detected from the output of the encoder 15.

The light source 41 of the position detection unit 40 is connected to the control device 90 via the power supply circuit 41 a.

Further, the camera 42 of the position detection unit 40 is connected via the drive circuit 42a, and the image processing device 43 is connected via the interface 43 a.

The control device 90 further includes: a CPU91 that performs various arithmetic processes; a ROM92 storing programs relating to operation control of the above-described respective configurations; a RAM93 that stores various data related to processing by the CPU91 in a work area; and an EEPROM94 as a storage unit for recording various setting data, sewing data, and the like.

As a recording medium for various setting data, sewing data, and the like, all nonvolatile recording media can be used instead of the EEPROM 94.

The sewing machine 10 further includes an operation panel 95 for inputting various settings or displaying various information, and the operation panel 95 is also connected to the control device 90 via an interface 95 a.

[ Sewing operation control ]

When the CPU91 of the control device 90 performs four-point zigzag sewing, if the encoder 15 detects a predetermined main shaft angle when the sewing machine motor 12 is driven, the needle swing motor 13 is controlled to move the sewing needle to the left or right with a predetermined needle swing width.

In the case of the four-point zigzag stitch, the left and right needle swing directions are switched every three needles, and therefore, the number of needles is counted based on the output of the encoder 15, and the needle swing motor 13 is controlled so that the needle swing direction is changed every three needles.

If the number of needles to be sewn is set in advance, the number of needles is counted during sewing, and if the target number of needles is reached, the sewing is ended.

In addition, when the number of needles is not preset, the input of a command for ending the sewing is received, and the sewing is ended.

[ adjustment control of end edge position ]

Next, the control of the edge position adjustment performed by the CPU91 of the control device 90 in the sewing process will be described based on the flowchart of fig. 8. The position adjustment control of the end edge part is repeatedly executed in a short period during sewing. The edge position adjustment control may be performed in synchronization with the needle fall cycle or may be performed in a shorter cycle.

The CPU91 of the control device 90 irradiates the detection light L to the upper surfaces of the objects to be sewn C1 and C2 via the light source 41 of the position detection unit 40 at the rear side (the upstream side in the feeding direction) of the needle drop position F in the sewing operation of the zigzag seam according to the control program stored in the ROM92 (step S1).

Since the objects to be sewn C1 and C2 are provided with the step by the step forming portion H1, the detection light L is cut along the X-axis direction at the boundary between the objects to be sewn C1 and C2, and the cut lights L1 and L2 are captured by the camera 42 (step S3).

The captured image is converted into image data, and the end positions of the cutoff lights L1, L2 are detected by image processing by the image processing device 43 (step S5).

The CPU91 obtains the shift amount in the Y axis direction from the base line K based on the detected position of the right end of the cutoff light L1, and determines the position adjustment amount in the Y axis direction of the workpiece C1 by the 1 st traverse mechanism 30A. Similarly, the amount of shift in the Y axis direction from the base line K is obtained from the position of the left end of the detected cutoff light L2, and the amount of position adjustment in the Y axis direction of the workpiece C2 by the 2 nd traverse mechanism 30B is determined.

Then, the CPU91 controls the respective traverse motors 38 of the 1 st and 2

nd traverse mechanisms

30A and 30B to adjust the positions of the objects C1 and C2 in the Y-axis direction (step S7).

Thus, the end edge portion C11 of the object to be sewn C1 and the end edge portion C21 of the object to be sewn C2 are positioned at the base line K in the position immediately before the needle drop position F, and are conveyed to the needle drop position by the feed mechanism, and the joining sewing is performed in a state where the end edge portion C11 of the object to be sewn C1 and the end edge portion C21 of the object to be sewn C2 are in close contact with each other.

[ technical effects of embodiments of the invention ]

As described above, since the sewing machine 10 is provided with the traverse mechanism 30 controlled based on the detection result of the position detecting unit 40, the sewing quality can be stably and highly maintained regardless of the skill of the operator.

Further, in the sewing machine 10, the light source 41 of the position detecting section 40 irradiates the linear detection light L along the Y-axis direction so as to straddle the end edge portions C11 and C21 of the two objects to be sewn C1 and C2, respectively, and the camera 42 captures the detection light L irradiated to the two objects to be sewn C1 and C2 from a direction different from the irradiation direction of the light source 41.

Further, since the irradiation position of the detection light L on the conveyance surface H in the state where there are no objects to be sewn C1, C2 is provided with the step forming portion H1 that forms a step between one object to be sewn C1 and the other object to be sewn C2, the detection light L is cut into the cut light L1 formed by cutting the object to be sewn C1 side and the object to be sewn C2 side and the cut light L2, and the positions of the right end portion of the cut light L1 and the left end portion of the cut light L2 in the Y axis direction can be detected favorably even when there is no gap between the objects to be sewn C1, C2, and the end edge portions C11, C21 of the objects to be sewn C1, C2 can be adjusted to appropriate positions on the base line K in the Y axis direction, and sewing can be performed without generating a gap. In addition, zigzag sewing can be performed so that the boundary between the object to be sewn C1 and the object to be sewn C2 is positioned at the center of the stitch in the Y-axis direction, and the sewing quality can be improved.

The irradiation direction of the detection light L from the light source 41 of the position detector 40 and the line-of-sight direction of the camera 42 are both set to any direction on the X-Z plane perpendicular to the conveyance plane H and parallel to the feed direction of the materials to be sewn C1, C2. Therefore, if the edge of the cutoff light L1 and the edge of the cutoff light L2 are aligned in the Y axis direction, it can be determined that the edge of the workpiece C1 and the edge of the workpiece C2 are close to or in contact with each other, and even if the workpieces are not aligned and separated, the calculation for correcting the separation distance on the screen in consideration of the inclination of the optical axis or the line of sight is not necessary, and therefore, the processing can be simplified and the accuracy can be ensured easily. On the other hand, in the case of performing irradiation or imaging from a direction inclined with respect to the X-Z plane, even when the edge portions of the object to be sewn C1 and the object to be sewn C2 come close to or abut against each other, separation occurs on the imaging screen, and further, in the case of the separation, calculation for correcting the separation distance on the screen in consideration of the inclination of the optical axis or the line of sight is required, which complicates the processing.

Further, since the irradiation direction of the detection light L from the light source 41 is perpendicular to the conveyance plane H, the cutoff light L1 and the cutoff light L2 can be detected with high brightness, the position in the Y axis direction of the right end portion of the cutoff light L1 and the left end portion of the cutoff light L2 can be detected more accurately, and the sewing quality can be further improved.

In particular, by using the laser light source as the light source 41, the detection light L formed of a single wavelength light can be irradiated, the influence of the ambient light can be easily suppressed, the cutoff light L1 and the cutoff light L2 can be detected favorably, the positions of the right end portion of the cutoff light L1 and the left end portion of the cutoff light L2 in the Y axis direction can be detected more accurately, and the sewing quality can be further improved.

[ others ]

The details shown in the above embodiments can be appropriately modified without departing from the scope of the invention.

For example, in the above embodiment, the case where the thickness of the sewn objects C1 and C2 is thicker than the step formed by the sewn objects C1 and C2 by the step forming portion H1 is exemplified, but in this case, the possibility of the run-in of the sewn object C1 positioned lower than the sewn object C2 with respect to the sewn object C2 is small, and therefore the need for the run-in is low.

In contrast, when the thickness of the sewn products C1 and C2 is smaller than the step formed by the sewn products C1 and C2 by the step forming portion H1, it is preferable to consider the penetration of the sewn product C1 into the sewn product C2.

Fig. 9 is a flowchart of the edge position adjustment control in consideration of the above-described submergence.

The edge position adjustment control may be performed in synchronization with the needle fall cycle or in a shorter cycle.

In the case of this end edge position adjustment control, the CPU91 of the control device 90 irradiates the detection light L to the upper surfaces of the objects to be sewn C1 and C2 via the light source 41 of the position detection unit 40 at the rear side (upstream side in the feeding direction) of the needle drop position F during the zigzag sewing operation (step S11) in accordance with the control program stored in the ROM 92.

Then, the cut light L1 of the object to be sewn C1 and the cut light L2 of the object to be sewn C2 formed by the difference in height of the difference in height forming portion H1 are photographed (step S13), and it is determined whether or not the gap N exists between the right end portion of the cut light L1 and the left end portion of the cut light L2 (step S15).

At this time, when there is no gap N between the right end of the cutoff light L1 and the left end of the cutoff light L2, the CPU91 controls the traverse motors 38 of the 1 st traverse mechanism 30A and the 2 nd traverse mechanism 30B to move the objects to be sewn C1 and C2 in directions away from each other so as to form a gap between the edge portion C11 of the object to be sewn C1 and the edge portion C21 of the object to be sewn C2 (step S17).

Then, the image is captured again (step S13), and it is determined that there is no gap N (step S15).

When there is no gap N in the determination, the end positions of the cutoff lights L1 and L2 are detected when there is a gap N (step S19).

Then, the CPU91 obtains the shift amount in the Y axis direction from the base line K based on the end positions of the cutoff lights L1 and L2, controls the respective traverse motors 38 of the 1 st traverse mechanism 30A and the 2 nd traverse mechanism 30B, and performs the position adjustment in the Y axis direction of the objects to be sewn C1 and C2 (step S21).

Thus, the end edge portion C11 of the sewn article C1 is not pushed into the sewn article C2, and the end edge portion C11 of the sewn article C1 and the end edge portion C21 of the sewn article C2 are joined and sewn in a state of being positioned at the base line K.

The height difference forming portion H1 is a projection projecting upward on the conveying surface H, but is not limited to this.

For example, as shown in fig. 10A and 10B, a level difference forming portion H1 formed of a substantially hemispherical protrusion may be provided on the right side of the conveyance surface H in the vicinity of the base line K.

Alternatively, as shown in fig. 11, a slope H11 may be provided at the end of the height difference forming portion H1 on the upstream side in the conveying direction, the slope being such that the change in height difference gradually increases. Alternatively, an inclined portion H12 may be provided at the end portion on the downstream side in the conveyance direction of the level difference forming portion H1, the inclined portion gradually reducing the change in the level difference. Either or both of the inclined portions H11 and H12 may be provided.

Further, although the case where the step forming portion H1 is provided on the right side of the base line K is exemplified, it is needless to say that the sewing object C1 may be provided on the left side so as to be higher than the sewing object C2.

In the example of the edge position adjustment control in fig. 8 and 9, the case where the respective traverse motors 38 of the 1 st traverse mechanism 30A and the 2 nd traverse mechanism 30B are controlled so that the edge C11 of the workpiece C1 and the edge C21 of the workpiece C2 are closely attached to each other without a gap is exemplified, but the position adjustment may be performed so that the minute gap N is formed within the allowable range of the sewing quality.

Claims

1. A zigzag sewing machine for joining and sewing two materials to be sewn together by butting end edges thereof against each other, comprising:

a position detecting unit that detects a position in the needle swing direction of each of two end edge portions of the workpiece to be sewn, which are respectively arranged on one side and the other side in the needle swing direction, on a conveying surface on an upstream side in the feed direction of the workpiece with respect to the lateral feed mechanism; and

2. Zigzag sewing machine according to claim 1,

the irradiation direction of the detection light of the light source and the visual line direction of the shooting part are both any direction on a plane which is vertical to the conveying surface and parallel to the feeding direction of the sewed object.

3. Zigzag sewing machine according to claim 1 or 2,

the irradiation direction of the detection light by the light source is a normal direction with respect to the transport surface.

4. Zigzag sewing machine according to any of claims 1 to 3,

the light source is a laser light source.

5. Zigzag sewing machine according to any of claims 1 to 4,

the control device determines whether a gap is generated between the end edge part of one sewed object and the end edge part of the other sewed object, moves the two sewed objects to form a gap under the condition that the gap is not generated, and then controls the transverse feeding mechanism to enable the end edge parts of the sewed objects to approach or abut against each other.