JP2011136127A - Sewing machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sewing machine which can suitably form a stitch along the cloth edge in the cloth feeding direction. <P>SOLUTION: The sewing machine includes: a feed dog 1 which is brought into contact with sewed objects C1, C2 on a needle plate 14 from lower side and performs a feed operation; a presser foot 19 being in contact with the workpiece from above; an end part adjusting mechanism for moving and adjusting the position of an end part along the stitch of the workpiece for a direction crossing a feed direction by the feed dog; detection means 24, 25 for detecting whether or not the end part of the workpiece is at predetermined positions; and control means 13 which controls to move the end part adjusting mechanism into a direction of separating from the detection means when the detection means detects existence of the end parts, and to control so that the workpiece moves in the direction of separating from the detection means when the detection means detects no existence of the end parts, if the detection of no end parts is continued until exceeding a threshold value determined for the time or the feeding distance continuing the detection state. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a sewing machine that forms a seam in accordance with an end of a workpiece.

The conventional sewing machine is provided with an upper manipulator and a lower manipulator that move each cloth in a direction intersecting the cloth feeding direction on the upper surface of the needle plate in order to keep the sewing margin constant.
The upper manipulator and the lower manipulator are each equipped with a roller that moves the cloth in the direction intersecting the cloth feed direction at the tip. During sewing, the roller is rotated by a pulse motor while detecting the cloth edge with a sensor, and the sewing allowance is constant. It keeps in.
In other words, if the sensor detects that there is a cloth edge, the roller is controlled to rotate in a direction away from the detection position of the sensor, and if it is detected that there is no cloth edge, the cloth edge is detected by the sensor. By controlling the rotation of the roller in the direction of entering the position, the cloth end is set to a fixed position (see, for example, Patent Documents 1 and 2).
Further, when the two cloths are overlapped and sewed together, a notch N (see FIG. 14) is a wedge-shaped (V-shaped) cut at the cloth edge for positioning the upper cloth and the lower cloth. ) May be formed in advance, and sewing may be performed using this as a mark.
Further, an end portion along the sewing direction of the cloth is cut into a predetermined shape by cutting, and a thread mark B (see FIG. 17) that is a fiber of the cloth pops out at such a cut end portion. May enter.
An apparatus for detecting the presence or absence of the notch N and the mark B is described in Patent Document 3 below. Patent Document 3 arranges cloth end detection points by optical fibers in a direction orthogonal to the cloth feeding direction, and detects the presence or absence of notch N or knot B based on a fuzzy rule in which a change in the detected cloth end position is set in advance. Is.

JP 58-192576 A JP 59-14881 A Japanese Patent Laid-Open No. 6-121887

  However, the apparatus of Patent Document 3 uses a group of optical fibers for cloth end detection, and the apparatus is expensive. Further, since the apparatus is based on fuzzy rules, the control system is complicated.

  An object of this invention is to form a seam stably along the edge part along the feed direction of a to-be-sewn material by simple structure and control.

  According to the first aspect of the present invention, there is provided a feed dog that performs a feed operation in contact with the workpiece on the needle plate from below, a presser foot that contacts the workpiece from above, and a direction orthogonal to the feed direction of the feed dog. An end adjusting mechanism for moving and adjusting the position of the end portion along the seam of the sewing product, a detecting means for detecting whether or not the end portion of the sewing product is at a predetermined position, and the end adjusting mechanism When the detection means detects the presence of the end, the movement control is performed in a direction away from the detection means, and when the detection means detects the absence of the end, the movement control is performed on the detection means side, Control means for controlling the distance from the end of the workpiece to the seam to be constant in a direction perpendicular to the feed direction, wherein the control means includes the end of the detection means When the detected state continues Or stores a certain threshold for the feed distance, and executes a movement control of by the adjustment drive source when exceeding the threshold to the detecting means side.

  The invention according to claim 2 has the same configuration as that of the invention according to claim 1, and the control means has a constant threshold for a time or a feed distance in which the detection state of the detection means with the end is continued. Is stored, and when the threshold value is exceeded, movement control in a direction away from the detection means by the adjustment drive source is executed.

  The invention described in claim 3 has the same configuration as that of the invention described in claim 1 or 2, and further includes threshold setting means for arbitrarily setting the fixed threshold.

  The invention described in claim 4 has the same configuration as that of the invention described in any one of claims 1 to 3, and also includes a feed leg that performs a feed operation in contact with the workpiece on the needle plate from above. The end adjustment mechanism includes an upper end adjustment mechanism that adjusts the position of the upper sewing product and a lower end adjustment mechanism that adjusts the position of the lower sewing product, and the end adjustment mechanism. The mechanism is composed of an upper detection means for detecting the position of the end portion of the upper sewing product and a lower detection means for detecting the position of the end portion of the lower sewing product, and the control means includes: For each of the upper sewing product and the lower sewing product, control is performed so that the distance from the end portion to the seam is constant, and movement control by the adjustment drive source is executed based on the threshold value. It is characterized by that.

In the invention according to claim 1, since the control for moving the end of the sewing product is not performed until the time or feed distance after detecting the absence of the end exceeds a certain threshold, the notch corresponds to the threshold. When the length of the sewing product is smaller than the length in the feed direction, the movement of the end of the sewing product is not performed, and therefore the presence of the notch does not affect the end of the sewing product without causing any effect. It is possible to form seams along.
In addition, detection of the end of the workpiece and notch countermeasures can be performed by a common detection means, and it is not necessary to provide a dedicated sensor and a processing circuit for notch countermeasures, thereby reducing the number of parts. Thus, it becomes possible to simplify the processing.

In the second aspect of the invention, since the control for moving the end of the sewing product is not performed until the time or the feed distance after detecting the presence of the end exceeds a certain threshold, the flare is in accordance with the threshold. When the length of the sewing product is smaller than the length in the feed direction, the movement of the end of the sewing product is not performed, and therefore, even if there is a fluff, no influence is exerted on the end of the sewing product. It is possible to form seams along.
In addition, the detection of the end of the sewing object and the countermeasure against the chipping can be performed by a common detecting means, and it is not necessary to provide a dedicated sensor for the countermeasure against the chipping and its processing circuit, thereby reducing the number of parts. Thus, it becomes possible to simplify the processing.

  Since the threshold value can be set in the invention according to the third aspect, an appropriate threshold value can be used according to the size of the notch or the mark that can be formed on the sewing product. Further, it is possible to avoid an excessive increase in the threshold value, and it is possible to minimize a decrease in the responsiveness of the movement of the workpiece when the sewing direction with respect to the end portion of the workpiece is actually deviated. .

  Since the invention according to claim 4 is provided with an adjustment mechanism and a detection means for each of the upper and lower workpieces, it is possible to reduce the influence of the notch on the sewing for each of the upper and lower workpieces. May make it possible to reduce the influence of injuries.

It is a perspective view of a vertical feed sewing machine. It is a schematic diagram which shows the needle drop vicinity. It is the perspective view which showed the mechanism regarding the drive of each roller. It is the perspective view from the lower part which showed the mechanism regarding the drive of a lower roller. It is the perspective view from the upper part which showed the mechanism regarding the drive of a lower roller. It is sectional drawing of a solenoid. It is the perspective view from the upper part which showed the mechanism regarding the drive of an upper side roller. It is the perspective view from the upper part which showed the mechanism regarding the drive of an upper side roller. It is a perspective view of a cloth sensor. It is a schematic diagram explaining the detection of a cloth sensor. It is a block diagram which shows the structure around a control apparatus. It is a flowchart which shows the flow of operation | movement of the up-and-down feed sewing machine at the time of cloth setting. It is a top view of the detection means for demonstrating cloth edge position control. It is explanatory drawing which expanded the detection position of the cloth end, and shows the case where a notch exists. It is explanatory drawing which expanded the detection position of the cloth end, and shows the case where a notch does not exist. It is explanatory drawing of the cloth movement amount table which shows the relationship between the setting pitch prepared for every spindle rotation speed, and determination time. It is explanatory drawing which expanded the detection position of the cloth end, and shows the case where a fluff exists. It is a flowchart which shows the detail of cloth edge position control.

(Overall configuration of the embodiment of the invention)
An embodiment of a vertical feed sewing machine according to the present invention will be described.
The vertical feed sewing machine is to sew two cloths C1 and C2 (articles to be sewn) placed on the throat plate while feeding them in the same direction, and changing the feed amount of the upper and lower cloths. This is a sewing machine that can be stitched together.
As shown in FIGS. 1 to 12, the vertical feed sewing machine 100 includes a cloth presser 19 as a presser foot, a feed dog 1, a feed foot 2, a lower roller 3, a lower pulse motor 4, and a lower connection. Mechanism 5, lower solenoid 6, upper roller 7, upper pulse motor 8, upper coupling mechanism 9, upper solenoid 10, separation plate 11, lower cloth sensor 24, upper cloth sensor 25, A control device 13 and a guide plate 20 are provided. Among these, the lower roller 3, the lower pulse motor 4, the lower coupling mechanism 5, the lower solenoid 6, the upper roller 7, the upper pulse motor 8, the upper coupling mechanism 9, and the upper solenoid 10 are included. The separation plate 11, the cloth sensors 24 and 25, and the guide plate 20 are end portions that move and adjust the positions of the end portions along the seam of the workpiece in the direction orthogonal to the feed direction by the feed dog 1. It constitutes the adjustment mechanism.

(Feed dog)
As shown in FIG. 2, the feed dog 1 is in contact with the lower cloth C <b> 1 (hereinafter, referred to as the lower cloth) of the two cloths placed on the needle plate 14 so as to feed from below. I do. The feed dog 1 is driven by a feed dog forward / backward feed mechanism (not shown) that gives a reciprocating motion along the cloth feed direction and a feed dog vertical feed mechanism (not shown) that gives a reciprocating motion along the vertical direction. . Thereby, the feed dog 1 moves so as to draw an elliptical orbit in a side view below the needle plate 14, and protrudes from the needle plate 14 when the feed dog 1 moves upward, and comes into contact with the lower cloth from below.

(Cloth presser and feed leg)
As shown in FIG. 2, the feed leg 2 is in contact with the upper cloth C <b> 2 (hereinafter referred to as the upper cloth) of the two cloths stacked on the needle plate 14 from above and performs a feeding operation. The cloth presser 19 touches the upper cloth C2 from above and presses the cloth. The feed foot 2 is driven by a feed foot forward / backward feed mechanism (not shown) that gives a reciprocating motion along the cloth feed direction and a feed foot vertical feed mechanism (not shown) that gives a reciprocating motion along the vertical direction. The cloth presser 19 only moves up and down by the above-mentioned feed leg up-and-down feed mechanism. Thereby, the feed leg 2 moves to draw an elliptical orbit in a side view above the needle plate 14, and comes into contact with the upper cloth from above when the feed leg 2 moves downward. Further, the cloth presser 19 moves up and down alternately with the feed leg 2 at a fixed position. That is, while the cloth presser 19 is separated above the upper cloth C2, the feed leg 2 moves downward while moving the feed leg 2 to perform the upper cloth C2 feeding operation, and the cloth presser 19 moves to the upper cloth C2. While in contact, the feed leg 2 moves upward while returning to the upstream side in the feed direction.

(Lower roller)
The lower roller 3 is supported by a swing arm 17 which will be described later so as to be able to move up and down. The lower roller 3 is provided so as to slightly protrude on the needle plate 14 when ascending, and is in contact with the lower cloth C1 from below and is fed by the feed dog 1 The cloth is reciprocated in a direction intersecting (orthogonal) with the direction. The lower roller 3 is rotatably supported by a lower coupling mechanism 5 (details will be described later). The outer surface of the lower roller 3 is formed in a sawtooth shape so that the lower roller 3 can reliably catch and move the cloth when contacting the cloth.
As shown in FIGS. 3 to 5, the lower roller 3 is connected to the output shaft of the lower pulse motor 4 by a belt 15.

(Lower pulse motor)
As shown in FIGS. 3 to 5, the lower pulse motor 4 is fixed to the base 16. The base 16 is provided with a swing arm 17 extending linearly. One end of the swing arm 17 is fixed to the base 16 together with the lower pulse motor 4, and the other end is a free end. The lower roller 3 is rotatably supported on the other end of the swing arm 17. The swing arm 17 is formed in a rod shape, and a belt 15 is stretched between the lower roller 3 and the output shaft of the lower pulse motor 4 so as to cover the swing arm 17. Thus, when the output shaft of the lower pulse motor 4 rotates, the rotation is transmitted to the lower roller 3 via the belt 15 to rotate the lower roller 3. That is, the lower pulse motor 4 functions as an “adjustment drive source”.

(Lower connection mechanism)
As shown in FIGS. 3 to 5, the lower coupling mechanism 5 includes the base 16 and the swing arm 17, the rotating shaft 21, the drive lever 22, and the transmission link 23 described above.
The base 16 to which the lower pulse motor 4 is fixed is formed in a pentagonal shape, and a rotating shaft 21 is provided at one corner thereof.
The rotating shaft 21 is rotatably supported by the sewing machine frame, and the direction of the shaft is parallel to the output shaft of the lower pulse motor 4. One end thereof is fixed to the base 16, and the base 16 rotates with the rotation of the rotary shaft 21. A drive lever 22 is provided at the other end of the rotating shaft 21.
The drive lever 22 is a rod-like plate material extending in the radial direction with the rotation shaft 21 as the center, and the rotation shaft 21 is clamped and fixed at one end thereof. One end of the transmission link 23 is connected and fixed to the other end of the drive lever 22 with a screw or the like.
The transmission link 23 is a plate material extending in the extending direction of the drive lever 22, and the plunger 62 of the lower solenoid 6 can come into contact with the other end of the transmission link 23 from below.
That is, the lower solenoid 6 is arranged so that the plunger 62 can move in the vertical direction. When the plunger 62 is extended, the transmission link 23 is pushed up, and when the plunger 62 is contracted, the transmission link 23 is not supported and moves downward. An urging member such as a spring that urges the transmission link 23 to move downward may be provided. That is, the transmission link 23 may be moved upward by the lower solenoid 6 and moved downward by the spring. Here, the housing 60 of the lower solenoid 6 is provided with a support base 61, and supports the transmission link 23 from below when the plunger 62 is not driven.

(Lower solenoid)
As shown in FIGS. 3 to 5, the lower solenoid 6 is arranged such that the plunger 62 moves along the vertical direction of the sewing machine (the vertical direction of the needle). The lower solenoid 6 changes the amount of movement of the plunger 62 in accordance with the amount of current that is energized. As a result, the lower solenoid 6 can control the pressing force on the cloth via the lower roller 3 in accordance with the energized current amount.
As shown in FIG. 6, the lower solenoid 6 includes a housing 60, a plunger 62, a coil frame 63, a coil 64, a magnetic material 65, and the like. The housing 60 has a nonmagnetic body 60C that supports the bearings 60A and 60B. The plunger 62 is supported by bearings 60A and 60B so as to be movable in the axial direction and not to be rotatable. The magnetic member 65 fixed to the plunger 62 has a cylindrical shape, and a step portion 65a for changing the diameter from the shaft center is formed in a part thereof. And by this shape, the specific stroke area (it explains in full detail later) where thrust does not depend on a stroke is obtained.

The lower solenoid 6 is attached in a direction to drive the plunger 62 in a direction in which the plunger 62 is drawn by energizing the coil 64. Then, the thrust for pulling the plunger 62 is increased as the energization current increases. This facilitates adjustment of the pressing force by the lower roller 3.
That is, the lower solenoid 6 functions as “lower pressing means”.

(Upper roller)
As shown in FIGS. 3, 7, and 8, the upper roller 7 is provided so as to be movable up and down above the needle plate 14, and comes into contact with the upper cloth from above when it descends and intersects the cloth feeding direction by the feed dog 1 The cloth is moved in a direction orthogonal to the upper surface of the needle plate 14. The upper roller 7 is rotatably supported by an upper coupling mechanism 9 (details will be described later). The outer surface of the upper roller 7 is formed in a sawtooth shape so that the upper roller 7 can reliably catch and move the cloth when it comes into contact with the cloth.
The upper roller 7 is connected to the output shaft of the upper pulse motor 8 by a belt 18 to be rotated.

(Upper pulse motor)
The upper pulse motor 8 is fixed to the base 31. The upper pulse motor 8 is provided with a swing arm 32 extending linearly. One end of the swing arm 32 is fixed to the upper pulse motor 8, and the other end is a free end. The upper roller 7 is rotatably supported at the other end of the swing arm 32. The swing arm 32 is formed in a plate shape, and the belt 18 is stretched between the upper roller 7 and the output shaft of the upper pulse motor 8 so as to cover the swing arm 32. Thereby, when the output shaft of the upper pulse motor 8 rotates, the rotation is transmitted to the upper roller 7 via the belt 18 to rotate the upper roller 7. That is, the upper pulse motor 8 functions as an “adjustment drive source”.

(Upper coupling mechanism)
The upper coupling mechanism 9 includes the base 31 and the swing arm 32, the rotation shaft 33, the drive lever 34, the transmission link 35, and the rotation link 36 described above.
The base 31 to which the upper pulse motor 8 is fixed is formed in a pentagonal shape, and a rotation shaft 33 is provided at one corner thereof.
The rotating shaft 33 is rotatably supported by the sewing machine frame, and the direction of the shaft is parallel to the output shaft of the upper pulse motor 8. One end of the base 31 is fixed to the base 31, and the base 31 rotates with the rotation of the rotary shaft 33. A drive lever 34 is provided at the other end of the rotating shaft 33.
The drive lever 34 is a plate material extending in the radial direction around the rotation shaft 33, and the rotation shaft 33 is clamped and fixed at one end thereof. One end of a transmission link 35 is rotatably connected to the other end of the drive lever 34.
The transmission link 35 is a rod-like plate material extending in a direction substantially orthogonal to the drive lever 34, and a plurality of connection holes 35a are formed along the longitudinal direction thereof. One end of a rotary link 36 is rotatably connected to the other end of the transmission link 35.
The rotary link 36 is rotatably supported by a plate material 71 attached to the housing 70 of the upper solenoid 10 in the vicinity of the center portion thereof. The other end of the rotary link 36 is rotatably connected to a plunger 72 that serves as an output shaft of the upper solenoid 10. The rotary link 36 is disposed substantially parallel to the drive lever 34.

(Upper solenoid)
The upper solenoid 10 is arranged such that the plunger 72 moves along the moving direction (longitudinal direction) of the transmission link 35.
The upper solenoid 10 includes a housing 70, a plunger 72, and the like. Since the internal configuration of the upper solenoid 10 is the same as that of the lower solenoid 6, the description thereof is omitted.
That is, the upper solenoid 10 functions as “upper pressing means”.

(Separator)
As shown in FIG. 7, one end of the separation plate 11 is fixed to the bottom surface of the support plate 44 with a screw (not shown). A guide plate 20 (not shown) is screwed to the upper surface of the support plate 44. The support plate 44 is connected to an adjustment dial 45 shown in FIG. 1 via a rack and a pinion gear (not shown). When the adjustment dial 45 is rotated, the position of the separation plate 11 and the guide plate 20 is adjusted with respect to the direction G perpendicular to the cloth feeding direction.
The separation plate 11 fixed to the bottom surface of the support plate 44 is disposed above the needle plate 14 between the upper roller 7 and the lower roller 3. The separation plate 11 is bent so that the tip of the separation plate 11 is lifted from the needle plate 14 when attached to the needle plate 14. Further, the separating plate 11 extends to the upstream side in the distribution feed direction from the rollers 3 and 7. That is, the separation plate 11 can divide the space on the needle plate 14 up and down, and the upper cloth C2 is sent to the upper side of the separation plate 11 and the lower cloth C1 is sent to the lower side.
Thus, the separation plate 11 is disposed between the two cloths C1 and C2, and the lower cloth 3 is sandwiched between the lower roller 3 and the lower surface of the separation plate 11, and the upper roller 7 and the upper surface of the separation plate 11 are sandwiched. Insert the upper cloth C2.

  The guide plate 20 is attached to the upper surface of the support plate 44 with screws so as to be disposed above the separation plate 11. The guide plate 20 has a lower surface facing the upper surface of the separation plate 11 and a gap through which the upper cloth C2 passes. The end of the guide plate 20 on the downstream side in the cloth feeding direction extends to the front of the upper roller 7, and the lower surface of the guide plate 20 guides the upper cloth C 2 into the gap between the upper roller 7 and the separation plate 11. Functions as a guide surface. Further, the end of the guide plate 20 on the upstream side in the cloth feeding direction is inclined so as to gradually move upward as it goes upstream.

(Cloth sensor)
As shown in FIGS. 9 and 10, the lower and upper cloth sensors 24 and 25 are used to keep the seam allowance (the length from one side edge (referred to as the cloth edge) of the cloth to the seam) constant during sewing. Whether or not the end is in a predetermined position is detected. As shown in FIG. 2, the cloth sensors 24 and 25 are provided close to the downstream side in the cloth feeding direction with respect to the lower roller 3 and the upper roller 7, respectively. As shown in FIGS. 9 and 10, these cloth sensors 24 and 25 are held by a common sensor base 41, are horizontally arranged, and are opposed to each other with a reflecting plate 46 whose both surfaces are reflecting surfaces. Has been. Each of the cloth sensors 24 and 25 includes a cloth presence sensor 42 on the front side and a cloth edge sensor 43 on the back side.
The front end of the sensor base 41 is formed in a substantially U shape when viewed from the cloth feeding direction, and the above-described reflecting plate 46 is held horizontally inside the sensor base 41. The cloth moving direction by the rollers 3 and 7 (hereinafter, the cloth moving direction by the upper and lower rollers 3 and 7 is referred to as the adjustment direction G, and the cloth feeding direction is provided on the inner lower surface and the inner upper surface of the U-shaped portion, respectively. The right-handed direction (left in FIG. 8) is called “forward” or “right”, and the left-handed direction (right in FIG. 8) is called “reverse” or “left”. ), Recesses 41a and 41b that are recessed downward and upward in a V shape are formed. Then, the reflection plate 46 is disposed at a position slightly higher than the upper surface of the needle plate 14 so as to be inserted between the lower fabric C1 and the upper fabric C2 that are conveyed while being stacked on the needle plate 14. .
Thus, the lower cloth C1 passes inside the U-shaped part of the sensor base 41 and passes between the reflector 46 and the lower concave part 41a, and the upper cloth C2 is inside the U-shaped part of the sensor base 41. Thus, it passes between the reflector 46 and the upper concave portion 41b.

Each recess 41a, 41b is formed in a V shape when viewed from the adjustment direction G.
On the two inclined surfaces of the recesses 41a and 41b, a cloth presence / absence sensor 42 including a light emitting sensor 42a and a light receiving sensor 42b is provided on the front side (opposite to the adjustment direction G). The cloth presence sensor 42 on the upper wall surface is a sensor that detects whether there is an upper cloth C2, and the cloth presence sensor 42 on the lower wall surface is a sensor that detects whether there is a lower cloth C1.
On the two inclined surfaces of each of the recesses 41a and 41b, a cloth end sensor 43 including a light emitting sensor 43a and a light receiving sensor 43b is provided on the back side (near the positive direction of the adjustment direction G). The cloth edge sensor 43 on the upper wall surface (41b side) is a sensor that detects whether the cloth edge of the upper cloth C2 is in a predetermined position, and the cloth edge sensor 43 on the lower wall surface (41a side) is the lower cloth C1. It is a sensor which detects whether the cloth edge is in a predetermined position.
The reflecting plate 46 reflects the light emitted from the light emitting sensors 42a and 43a. If there is no cloth edge on the optical path, the light reflected by the reflecting plate 46 has high intensity and the light receiving sensors 42b, Light is received at 43b.

With the above structure, the upper cloth C2 can enter between the reflecting plate 46 and the cloth presence sensor 42 and the cloth end sensor 43 on the upper wall surface, and the lower cloth C1 can be inserted between the reflecting plate 46 and the cloth presence sensor 42 on the lower wall surface. It is possible to enter between the cloth end sensor 43. If the cloth has entered, since the cloth blocks the light from the light emitting sensors 42a and 43a and is not reflected by the reflecting plate 46, the light receiving sensors 42b and 43b cannot detect the light. Using this principle, the presence / absence of cloth and the edge of the cloth are detected.
That is, the lower cloth sensor 24 functions as “lower detection means”, and the upper cloth sensor 25 functions as “upper detection means”.

(Control device)
As shown in FIG. 11, the control device 13 includes a CPU 51 that performs various arithmetic processes, drive control of the feed dog 1 and feed leg 2, drive control of the pulse motors 4 and 8, and drive control of the solenoids 6 and 10. ROM 52 storing a program related to the CPU 51 and a RAM 53 storing various data related to processing of the CPU 51 in a work area.
When the cloth presence / absence sensor 42 detects that there is a cloth, the control device 13 detects the cloth edge with the cloth edge sensor 43, and based on the detection result, the rotation direction and rotation of the rollers 3 and 7 are detected. The amount is determined and each pulse motor 4, 8 is driven. Further, the control device 13 drives the solenoids 6 and 10 in order to adjust the pressing force of the cloths by the rollers 3 and 7 according to the amount of squeezing when performing staking sewing.
That is, the control device 13 functions as a “control unit”.
The control device 13 includes a sewing motor 56 that is a driving source for the sewing operation and the feed dog 1 and the feed leg 2, an encoder 57 that detects the shaft angle, pulse motors 4 and 8, solenoids 6 and 10. The cloth presence / absence sensors 42 and 42 of the upper and lower cloth sensors 24 and 25 and the cloth edge sensors 43 and 43 are connected to each other.
The control device 13 is connected with an operation panel 54 as a setting input means for inputting various settings via an interface (not shown), and a display device 55 for displaying setting contents and the like.

(Cloth setting operation before sewing)
Next, the cloth setting operation before sewing the vertical feed sewing machine will be described.
As shown in FIG. 12, when setting the cloth before the execution of sewing, the control device 13 determines whether or not the cloth presence sensor 42 has detected the lower cloth (step S1).
In step S1, when the control device 13 determines that the cloth presence sensor 42 has detected the lower cloth (step S1: YES), the control device 13 drives the lower solenoid 6 to raise the lower roller 3. (Step S2). Further, the control device 13 drives the lower pulse motor 4 (step S3). Thereby, the lower roller 3 contacts the lower cloth while rotating. When the lower roller 3 comes into contact with the lower cloth, the lower cloth 3 is pulled into the recess 41 a of the sensor base 41 by the rotation of the lower roller 3.
Next, the control device 13 determines whether or not the cloth edge sensor 43 has detected the lower cloth (step S4).
In step S4, when the control device 13 determines that the cloth end sensor 43 has detected the lower cloth (step S4: YES), the control device 13 stops driving the lower pulse motor 4 (step S5).

Next, the control device 13 determines whether or not the cloth presence sensor 42 has detected an upper cloth (step S6).
In step S6, when the control device 13 determines that the cloth presence sensor 42 has detected the upper cloth (step S6: YES), the control apparatus 13 drives the upper solenoid 10 to lower the upper roller 7 (step S6). S7). Further, the control device 13 drives the upper pulse motor 8 (step S8). Thereby, the upper roller 7 contacts the upper cloth while rotating. When the upper roller 7 comes into contact with the upper cloth, the upper cloth is drawn into the recess 41 b of the sensor base 41 by the rotation of the upper roller 7.
Next, the control device 13 determines whether or not the cloth edge sensor 43 has detected the lower cloth (step S9).
In step S9, when the control device 13 determines that the cloth edge sensor 43 has detected the upper cloth (step S9: YES), the control device 13 stops driving the upper pulse motor 8 (step S10). This completes the cloth setting operation before sewing.

(Cloth edge position control)
Next, the cloth edge position control of the vertical feed sewing machine 100 will be described.
FIG. 13 is a plan view of the detection means 12 for explaining the cloth edge position control. In the vertical feed sewing machine 100, during the sewing, the upper and lower cloth end sensors 43 detect the cloth end, and the upper pulse motor so that the cloth ends of the upper and lower cloths always pass the position of the cloth end sensor 43. 8 and the operation of the lower pulse motor 4 are controlled.
The cloth edge sensor 43 has a detection light intensity threshold determined in advance by the light receiving sensor 43b, and the controller 13 has a large area shielded by the cloth edge when the output of the light receiving sensor 43b is less than the threshold. From the above, it is determined that there is a cloth edge (detection), and if it is equal to or greater than the threshold value, it is determined that there is no cloth edge (non-detection) because the area is not shielded or is small. The cloth edge detection by the cloth edge sensor 43 is executed periodically (for example, every 1 [msec]) during sewing.

The upper cloth C2 will be described as an example. When the cloth end of the upper cloth C2 is detected by the cloth end sensor 43 (two-dot chain line in FIG. 13), the control device 13 moves the upper pulse motor 8 in the direction opposite to the adjustment direction G. When the cloth end of the upper cloth C2 is not detected by the cloth end sensor 43 (two-dot chain line in FIG. 13), the upper pulse motor 8 is driven and controlled in the positive direction of the adjustment direction G. Note that the same control is performed on the lower cloth C1.
That is, as a result, the cloths C1 and C2 are alternately moved to the left and right around the cloth end sensor 43 to feed the cloth, thereby forming a seam along the cloth end.
In FIG. 13, for the sake of explanation, the swing width is shown larger, but actually the cloth feed is performed with a smaller swing width.

Furthermore, the control device 13 is characterized in that the following control is performed as a countermeasure against notches in the cloth edge position control.
FIG. 14 is an explanatory diagram enlarging the cloth edge detection position. As shown in the figure, if the notch N is present at the cloth edge within the detection area A of the cloth edge sensor 43, the output of the light receiving sensor 43b becomes equal to or greater than the threshold value, and the control device 13 determines that there is no cloth edge. As a result, if no countermeasure is taken, the cloth is moved in the positive direction of the adjustment direction G even if the cloth edge is in an appropriate position.
Accordingly, in the cloth edge position control of the control device 13, the "no cloth edge" is output until the cloth feeding is performed for the predetermined determination distance L1 after the output of the light receiving sensor 43b is switched to the "no cloth edge" state. When the determination is continued, the operation control of the upper pulse motor 8 and the lower pulse motor 4 is performed so that the cloth is moved in the positive direction of the adjustment direction G (the direction in which the cloth edge is present).
This determination distance L1 is desirably a distance longer than the length of a general notch N in the cloth feeding direction, and the numerical value can be set from the operation panel 54 described above.

  According to the above control, as shown in FIG. 15, if it is a cloth end without notch N that is detected by the light receiving sensor 43b, the period during which the determination distance L is being fed is detected. The detection result of the light receiving sensor 43b that is executed automatically is determined to be “no cloth end” every time. However, when it is determined that the cloth end is not present by the notch N, when the position of the notch N is passed, It is determined that there is a cloth edge. Accordingly, by further determining whether or not to maintain the determination during the feeding of the determination distance L1 after the determination of “no cloth end” is made in this way, Detection can be prevented.

Further, in order to determine the elapse of the determination distance L1, the control device 13 needs to monitor whether or not the determination distance L1 has been fed from the time when the light receiving sensor 43b detects that there is no cloth edge. There is.
The vertical feed sewing machine can set a feed pitch, which is a cloth feed amount for each stitch, from a feed pitch dial 60 provided on the head of the sewing machine. The set feed pitch is sent to the control device 13 by a potentiometer (not shown) linked to the feed pitch dial 60. Note that it is easy to set the feed pitch from the operation panel 54 instead of the feed pitch dial 60.
It is possible to obtain a change in the cloth feed amount from the spindle speed (rotation speed) of the sewing machine based on the set pitch and the output of the encoder 57. That is, the control device 13 monitors whether or not the determination distance L1 has been fed based on the elapsed time from the detection of “no cloth end” (referred to as “determination time”).
FIG. 16 is an explanatory diagram of a cloth movement amount table showing the relationship between the set pitch prepared for each spindle rotation speed and the determination time.
The cloth movement amount table in FIG. 16 shows an example in which the determination distance L1 is set to 2 [mm] on the assumption that the notch N is less than 2 [mm] at the maximum. The left table of FIG. 16 is a cloth movement amount table corresponding to a spindle rotation speed of 1000 [rpm]. When the spindle rotation speed is 1000 [rpm], the cloth feed for the set pitch is performed by one rotation of the spindle. That is, the determination time is calculated by the following formula (1).
[Determination time] = [Determination distance L1] / ([Setting pitch] / [Cycle]) (1)
Since the period is 0.06 [s], for example, the time required for feeding the determination distance L1 is 0.12 [s] if the set pitch is 1 [mm], and 0.06 [s] if the set pitch is 2 [mm]. ] If the set pitch is 3 [mm], it will be 0.04 [s]. Although only a part of the set pitch is shown in FIG. 16, the grain is set more finely in the cloth movement amount table. The right table of FIG. 16 shows a cloth movement amount table with a spindle speed of 2000 [rpm], but the determination time is similarly calculated by the above equation (1).
Further, FIG. 16 shows only the cloth movement amount table with spindle rotation speeds of 1000 [rpm] and 2000 [rpm], but more spindle rotation speeds are prepared.
When the cloth edge sensor 43 detects that there is no cloth edge at the time of sewing, the control device 13 obtains the spindle rotational speed from the output of the encoder 57 at that time, reads the corresponding cloth movement amount table, and determines from the current set pitch. Identify time. Depending on whether or not the detection of “no cloth edge” continues until the determination time elapses after the start of time counting, whether the detection of “no cloth edge” is actually caused by the detection of the cloth edge or notch N It is determined whether the error is caused by false detection.
That is, when the light receiving sensor 43b detects “no cloth end”, the control device 13 reads the current set pitch, obtains the spindle rotation speed from the detection of the encoder 57, and reads the corresponding cloth movement amount table. The determination time is specified from the current set pitch. Thereafter, it is determined whether the light receiving sensor 43b, which is performed every 1 [msec], keeps detecting “no cloth edge” until the determination time elapses. When the determination time has elapsed, the light receiving sensor 43b detects that the cloth edge has been detected, and moves the cloth in the reverse direction of the adjustment direction G. Before the determination time elapses, the detection state of the light receiving sensor 43b is “cloth edge. When it is switched to “Yes”, the cloth is not moved in the direction opposite to the adjustment direction G because it is caused by erroneous detection of the notch N.

In addition, the control device 13 is characterized in that the following control is performed as a countermeasure against the fluffing in the cloth edge position control.
FIG. 17 is an explanatory diagram enlarging the cloth edge detection position. As shown in the figure, if there is a mark B at the cloth edge in the detection area A of the cloth edge sensor 43, the output of the light receiving sensor 43b becomes less than the threshold value, and the control device 13 determines that “the cloth edge is present”. As a result, if no measures are taken, the cloth is moved in the direction opposite to the adjustment direction G even if the cloth edge is in an appropriate position.
Accordingly, in the cloth edge position control of the control device 13, when the determination of “with cloth edge” is continued until the cloth feeding is performed by the predetermined determination distance L2, the cloth moves in the direction opposite to the adjustment direction G (cloth edge). The operation of the upper pulse motor 8 and the lower pulse motor 4 is controlled so as to be moved in the direction of “none”.
The determination distance L2 is desirably a distance longer than the length of the general rib B in the cloth feeding direction, and the numerical value can be set from the operation panel 54 described above.
As in the case of the notch N described above, if it is detected that the cloth end is detected by the light receiving sensor 43b, the cloth is not subjected to the bleed B, and is periodically executed while the determination distance L2 is being fed. The detection result of the light receiving sensor 43b is determined to be “cloth end present” every time. However, if it is determined that the cloth end is present by the incision B, the cloth end is passed when the position of the incision B is passed. The determination is “None”. Therefore, by further determining whether or not to maintain the determination during the feeding of the determination distance L2 after the determination of “with cloth edge” is made in this way, Detection can be prevented.
Further, since the method for determining the passage of the determination distance L2 is exactly the same as the method for determining the determination distance L1 of the notch N described above, the description thereof is omitted.

Hereinafter, the cloth edge position control will be described in detail based on the flowchart of FIG. Although the cloth edge position control for the upper cloth C2 and the lower cloth C1 is performed individually, the control contents are almost the same. Therefore, in this flowchart, only the process for the upper cloth C2 is shown, and the control of the lower cloth C1 is performed. The description will be omitted.
First, cloth edge detection by the periodic cloth edge sensor 43 is executed (step S21). As a result, when the detected light amount of the light receiving sensor 43b is less than the threshold value and “cloth edge is present” is determined (step S21: YES), the current set pitch is read and the spindle rotation of the sewing machine is output from the output of the encoder 57. The number is calculated (step S22).
Further, the cloth movement amount table is specified from the spindle rotation speed, and the determination time required for the cloth feeding of the determination distance L2 is acquired according to the set pitch with reference to the cloth movement amount table. Then, the control device 13 starts measuring the determination time (step S23). Then, after waiting for the next detection cycle of the cloth edge sensor 43 (step S24), the cloth edge sensor 43 detects the cloth edge again (step S25).
As a result, when the cloth edge is not detected (step S25: NO), the cloth edge detection in step S21 is assumed to be an erroneous detection due to the insufflation B, and the process proceeds to step S26. Direction). At this time, the counting of the determination time started in step S23 ends. Then, the process proceeds to step S36. Thus, after the next detection cycle elapses, the process returns to step S21, and the process proceeds to the next new cloth edge detection.

  On the other hand, when it is detected again that “cloth end is present” in step S25 (step S25: YES), the elapse of the determination time is determined (step S27), and when it has not elapsed (step S27: NO), the process proceeds to step S26. When the process is returned and elapsed (step S27: YES), it is assumed that the detection of the presence of the cloth end in step S21 is appropriate, and the cloth is moved in the left direction (reverse direction) (step S28). At this time, the counting of the determination time started in step S23 ends. Then, the process proceeds to step S36. Thus, after the next detection cycle elapses, the process returns to step S21, and the process proceeds to the next new cloth edge detection.

On the other hand, if it is determined in step S21 that the amount of light detected by the light receiving sensor 43b is less than the threshold value and “no cloth end” determination is obtained (step S21: NO), the current set pitch is read and the output of the encoder 57 is output. From this, the spindle speed of the sewing machine is calculated (step S29).
Furthermore, the cloth movement amount table is specified from the spindle rotation speed, and the determination time required for the cloth feeding of the determination distance L1 is acquired according to the set pitch with reference to the cloth movement amount table. Then, the control device 13 starts measuring the determination time (step S30). Then, after waiting for the next detection cycle of the cloth end sensor 43 (step S31), the cloth end sensor 43 executes the cloth end detection again (step S32).
As a result, when the cloth edge is detected (step S32: YES), it is determined that the detection of no cloth edge in step S21 is a false detection by the notch N, and the process proceeds to step S33, and the cloth is moved in the left direction (reverse direction). Direction). At this time, the determination of the determination time started in step S30 ends. Then, the process proceeds to step S36. Thus, after the next detection cycle elapses, the process returns to step S21, and the process proceeds to the next new cloth edge detection.

On the other hand, when it is detected again in step S32 that “no cloth end” (step S32: NO), the elapse of the determination time is determined (step S33), and when it has not elapsed (step S33: NO), the process proceeds to step S31. When the process is returned and elapsed (step S33: YES), it is assumed that the detection of no cloth end in step S21 is appropriate, and the cloth is moved in the right direction (forward direction) (step S34). At this time, the determination of the determination time started in step S30 ends. Then, the process proceeds to step S36. Thus, after the next detection cycle elapses, the process returns to step S21, and the process proceeds to the next new cloth edge detection.
The cloth end position control is repeatedly executed until the end of the upper cloth C2 and the lower cloth C1 is detected by the cloth presence sensor 42 and the sewing is completed.

(Effect of embodiment)
As described above, the control device 13 of the vertical feed sewing machine 100 moves the cloth end until the feed distance after detecting the absence of the end of each of the lower cloth C1 and the upper cloth C2 exceeds the determination distance L1. Therefore, when the notch N is smaller than the determination distance L1 in the cloth feeding direction, the operation of moving the cloth edge is not performed. Therefore, even if the notch N exists, no erroneous detection is performed. It is possible to form seams along the ends of the cloths C1 and C2.

  Similarly, the control device 13 does not perform control to move the cloth edge until the feeding distance after detecting the presence of the edge exceeds the determination distance L2 for each of the lower cloth C1 and the upper cloth C2. Therefore, when the incision B is smaller than the determination distance in the cloth feeding direction, the movement of the cloth edge is not performed. Therefore, even if the notch B exists, each cloth C1, C2 is not erroneously detected. It is possible to form a seam along the end.

In addition, since the lower and upper cloth sensors 24 and 25 that detect the ends of the cloths C1 and C2 are used to prevent erroneous detection of the notch N and the hip B, the notch N and the hip B are detected. Therefore, it is not necessary to provide a dedicated sensor and a processing circuit therefor, so that the number of parts can be reduced and the processing can be simplified.
Further, in the vertical feed sewing machine 100, the determination distances L1 and L2 that are threshold values for determining the presence or absence of the notch N and the flare B can be set and input by the operation panel 54, so that a more appropriate determination distance can be set. By setting, it becomes possible to more appropriately adjust the balance between the identification of the notch N and the cutout B and the followability of the cloth feed.

The vertical feed sewing machine 100 includes a lower solenoid 6 that presses the lower roller 3 against the lower cloth C1, and an upper solenoid 10 that presses the upper roller 7 against the upper cloth C2. Since the control device 13 can arbitrarily control the thrust force of the solenoids 6 and 10, at the time of squeeze stitching, the control force of the lower cloth C1 and the upper cloth C2 can be controlled at any squeeze amount. Sewing can be realized.
In addition, since the feed pitch for each stitch fluctuates when performing shampoo sewing, in comparison with the determination distances L1 and L2, the pressing force to the lower cloth C1 or the upper cloth C2 or each solenoid for determining it. The drive current values of 6 and 10 may be taken into account for calculating the movement distance of the cloth. For example, if the drive current value of the solenoid 6 or 10 increases, the pressing force to the lower cloth C1 or the upper cloth C2 increases and the cloth movement speed decreases, so that the determination time acquired in the cloth movement amount table is reduced. Thus, the determination time may be corrected to be longer by multiplying by a coefficient that increases as the drive current value increases.

(Other)
In the control device 13, for example, whether or not the cloth edge position control including the determination of the presence / absence of the notch N and the cloth edge position control including the determination of the presence / absence of the knot B are individually set by the operation panel 54. It may be possible. That is, when the determination of the notch N and the cutout B is not performed, when the cloth end is detected or the cloth end is not detected, the cloth is started to move left and right without waiting for the determination time to elapse. Become.
Similarly, only one of the cloth end position control including the determination of the presence / absence of the notch N and the cloth end position control including the determination of the presence / absence of the inflection B may be executed.
By enabling the setting as described above, the cloth edge position control including the determination of the presence / absence of the notch N is executed only for the cloth having the notch formed, or the presence / absence of the mark B is determined only for the cloth where the mark B is likely to occur. It is possible to take countermeasures against fluffing according to necessity, such as executing cloth edge position control including determination.

Moreover, you may add to the said control apparatus 13 the function to measure the length of the cloth feed direction of the notch N or the hip B.
For example, in the flowchart of FIG. 18 described above, if “NO” is determined in the step S25, the determination of “cloth end present” in the step S21 is caused by the hip B, so that the process starts in the step S23. The cloth movement distance from the determination of “with cloth edge” in step S21 to the time until the determination of “NO” in step S25, the spindle rotation speed, and the set pitch is made. By calculating, the cloth movement distance can be regarded as the length of the cloth B in the cloth feeding direction.
Similarly, if “YES” is determined in step S32, the determination of “no cloth end” in step S21 is caused by the notch N, and therefore the time count started in step S30 is changed to “ By calculating the cloth movement distance from the determination of “no cloth edge” in step S21 based on the time measured until “YES” is determined, the spindle speed, and the set pitch, the cloth movement distance is calculated. The moving distance can be regarded as the length of the notch N in the cloth feeding direction.
These fluff lengths or notch lengths may be stored in the RAM 53 or controlled to be displayed on the display device 55.
As described above, since the lengths of the notches N and the edges B in the cloth feeding direction can be acquired, the determination distance L1 or L2 set from the operation panel 54 can be set to a more appropriate value.

The control means 13 periodically executes the cloth edge detection by the cloth edge sensor 43 (every 1 [msec]), but the cloths C1 and C2 have a small movement distance determined in advance in the cloth feeding direction. Control may be performed so that the cloth edge detection is performed by the cloth edge sensor 43 each time the movement is performed.
In this case, the movement distance of the cloths C1 and C2 is not calculated only when it is determined that there is a cloth edge, but the output of the encoder 57 is always monitored during the sewing to obtain the spindle angle, and the spindle angle and the set pitch are used. The movement amount of the cloths C1 and C2 is constantly or periodically calculated, and whenever the movement of the predetermined movement amount is performed, the cloth edge detection is performed by the cloth edge sensor 43, and the cloth edge position control is performed. May be.

In the vertical feed sewing machine 100, the cloth feed distance threshold (determination distances L1 and L2) is used to determine the presence or absence of the notch N or the fluff B, but it is simpler regardless of the rotational speed of the sewing machine motor 56. The direction of cloth movement is determined by whether or not the same detection state continues for a certain threshold time after the detection of “no cloth edge” or “with cloth edge”, with a certain time as a threshold. Control to determine may be performed.
That is, if the detection continues for a certain determination time after the detection of “no cloth edge” is detected, the cloth is moved to the right (positive direction) assuming that there is no actual cloth edge, and the detection continues. If it changes to “with cloth end” without any change, the cloth is moved to the left (reverse direction) as if it was a notch T. Similarly, if the detection continues for a certain period of time after the detection of “with cloth edge” is detected, the cloth is moved to the left (reverse direction) as if the cloth edge is actually detected, and the detection is performed. If it changes to “no cloth edge” without continuing, the cloth is moved to the right (in the positive direction) as if there was a fluff B.
In this case as well, the elapsed time between the change from the detection of “no cloth edge (with)” to the detection of “with cloth edge (without)” is counted, and the rotational speed and setting of the sewing machine motor 56 at that time are set. It is possible to obtain the size of the notch N (or knot B) in the cloth feeding direction based on the pitch.

  In the cloth edge position control described above, an example is shown in which the determination time is acquired from the cloth movement amount table in step S22 or S29. However, the determination time may be calculated each time using the above-described equation (1). .

1 Feed dog 2 Feed foot 3 Lower roller (end adjustment mechanism)
4 Lower pulse motor (adjustment drive source)
5 Lower connection mechanism (end adjustment mechanism)
6 Lower solenoid (end adjustment mechanism)
7 Upper roller (end adjustment mechanism)
8 Upper side pulse motor (adjustment drive source)
9 Upper connection mechanism (end adjustment mechanism)
10 Upper solenoid (end adjustment mechanism)
11 Separation plate (end adjustment mechanism)
13 Control device (control means)
14 Needle plate 19 Cloth presser (presser foot)
20 Guide plate (end adjustment mechanism)
24 Lower cloth sensor (detection means)
25 Upper cloth sensor (detection means)
54 Operation panel (threshold setting means)
C1 Underclothes (Sewing products)
C2 Top cloth (sewn product)

Claims (4)

A feed dog that performs feed operation by contacting the workpiece on the needle plate from below;
A presser foot in contact with the workpiece from above,
An end adjustment mechanism that moves and adjusts the position of the end along the seam of the sewing product in a direction orthogonal to the feed direction by the feed dog;
Detecting means for detecting whether or not the end of the sewing product is in a predetermined position;
The end adjustment mechanism is controlled to move away from the detection means when the detection means detects the presence of the end, and is moved to the detection means when the detection means detects no end. A sewing machine comprising: control means for controlling and controlling the distance from the end of the sewing product to the seam in a direction orthogonal to the feed direction;
The control means stores a fixed threshold for a time or a feeding distance in which the detection state of the detection means without the end is continued, and when the threshold is exceeded, the adjustment drive source moves to the detection means A sewing machine characterized by executing control.   The control means stores a fixed threshold value for a time or a feeding distance in which the detection state of the detection means with the end portion continues, and in a direction away from the detection means by the adjustment drive source when the threshold value is exceeded. The sewing machine according to claim 1, wherein the movement control is performed.   The sewing machine according to claim 1, further comprising a threshold setting unit configured to arbitrarily set the fixed threshold. Provided with a feed leg that performs a feed operation in contact with the workpiece on the needle plate from above,
The end adjustment mechanism includes an upper end adjustment mechanism that adjusts the position of the upper sewing product and a lower end adjustment mechanism that adjusts the position of the lower sewing product,
The end adjustment mechanism is composed of upper detection means for detecting the position of the end of the upper sewing product and lower detection means for detecting the position of the end of the lower sewing product,
The control means controls each of the upper sewing product and the lower sewing product so that the distance from the end portion to the seam is constant, and based on the threshold value, by the adjustment drive source The sewing machine according to any one of claims 1 to 3, wherein movement control is executed.

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