JP2009131626A - Welting machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a welting machine for reducing the sliding sound of a center knife. <P>SOLUTION: Control means in the welting machine forms lock stitch parts P1 and Q1 of two stitch lines, also forms a straight cut, then forms the stitch of a back tuck stitch part Q2 continued to the lock stitch part Q1 of one stitch Q positioned on the cloth feed direction downstream side of the two stitch lines P and Q, then idly feed a cloth toward the cloth feed direction downstream side to the start position of the stitch of the back tuck stitch part Q2, then forms the stitch of the lock stitch part P2 continued to the lock stitch part P1 of the other stitch P positioned on the cloth feed direction upstream side of the two stitch lines, also forms the straight cut, then forms the stitch of a back tuck stitch part P3 continued to the lock stitch part P2 of the other stitch P, and also controls the drive of a spindle motor, a single needle stop mechanism, a large pressing mechanism and a knife motor so as to reduce the elevating/lowering speed of the center knife when idly feeding the cloth. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an edge stitch sewing machine.

It has two needle bars each holding a sewing needle, and these needle bars are moved up and down and swinged independently of each other, and the cloth made of the cloth and the ball cloth is fed in the forward and reverse directions, and the center knife. There is known a bead stitch sewing machine capable of forming a slit between two seams while forming two seams on a cloth by raising and lowering.
The needle bar and center knife are arranged at a predetermined interval on the sewing machine arm. The vertical movement speed of the center knife and the feed pitch of the center knife are adjusted to prevent unnecessary movement and to optimize the operation. (For example, refer to Patent Document 1).
The edge stitch sewing machine holds the cloth on the body cloth and allows the two sewing needles to be inserted into the leading end downstream in the cloth feeding direction while sewing, and the cloth around the position where the sewing needle moves up and down. A binder is provided in which a pair of grooves along the cloth feeding direction are individually formed so as to correspond to the two sewing needles so as to be able to press the ball cloth. Further, on both sides of the binder, there are provided large pressing mechanisms that descend and press and hold the cloth and the drape while conveying the cloth and the drape along the cloth feeding direction. When forming the seam, the needle bar is moved up and down and the needle swings while the body and the cloth are transported along the cloth feeding direction by the large pressing mechanism while lowering the binder and holding the ball, and the center knife. Move up and down.
Here, at the rear end of the seam at the end of the sewing, in order to prevent fraying of the thread and to strengthen the sewing, the cloth made of body cloth and ball cloth is already sent in the direction opposite to the normal forward feed direction. There is a case where backtack stitching for forming a seam over the formed seam or condensation stitching for making the stitch pitch minute is performed. In addition, the rear end portions of the two seams are not always formed side by side, and the positions of the rear end portions of the respective seams (also simply referred to as rear end positions) are shifted along the cloth feeding direction. Sometimes formed.
JP 2006-218189 A

By the way, in the formation of the seam in which the position of the rear end portion of the seam is shifted in the cloth feeding direction, in order to perform back tack sewing for each, as shown in FIG. Forming the seam A1 of the main stitch portion with the sewing needle and forming a straight cut, then interrupting the formation of the other seam to form the stitch A2 of the back tack seam of one seam, Consider a method in which only the cloth A3 is fed to form a straight cut line with the seam A4 of the main seam part of the other seam, and further a seam A5 of the back tack seam part is formed continuously to the seam A4 of the main seam part. It is done. Actually, the seam of the main seam portion of each of the two seams overlaps with the seam of the back tack seam portion. However, in FIG. 17, the seam of the back tack seam portion is expanded laterally for the sake of explanation. Show.
Further, when performing condensation stitching, as shown in FIG. 18, the stitch C1 of the main stitching portion by two sewing needles is formed up to the end position of the main stitching portion of one stitch, and a straight cut is formed. Next, the formation of the other seam is interrupted to form the stitch C2 of the condensed seam of one seam, and then only the cloth is fed forward C3 and the seam C4 and the main seam C4 of the other seam are formed. A conceivable method is to form the seam C5 of the condensed seam that follows the seam and form a straight cut.
In the above sewing method, it is absolutely necessary to feed the cloth by an idle feed. Here, in the idle feeding of the cloth, only the place where the sewing and the cloth cutting have already been completed is returned. At the time of idle feeding, the sewing machine motor is stopped and the needle bar does not move up and down, but the center knife continues to move up and down even though the cut to be formed by the start of idle feeding has been formed. This is because the lifting movement of the center knife is not stable for a while after starting the center knife, so it is inefficient to stop it only during idle feeding in order to form the remaining cut after the idle feeding. That's why.
However, at the time of idling, the cloth has already been cut, and the center knife does not have a resistance cloth. Therefore, a louder sliding sound is generated between the center knife and the fixed knife than when the cloth is being cut. In addition, when the center knife is activated, operating noise is also generated from the link members that make up the center knife mechanism. However, since the sewing machine motor is stopped during idle feeding, these sliding noise and operating noise are generated. Since there was no noise to wipe out, the sliding noise of the center knife and the operating noise of the center knife mechanism were very annoying for the operator.

  Therefore, the present invention has been made to solve the above-described problems, and an object of the present invention is to provide an edge stitch sewing machine capable of reducing the sliding noise of the center knife.

The invention according to claim 1 has two needle bars that are respectively held by two sewing needles and are driven by a spindle motor to move up and down, and each sewing needle can be individually stopped at the raised position. A needle up-and-down movement mechanism having a one-needle stop mechanism configured as described above, and sewing the body cloth and the drape into two seams by the vertical movement of the two needle bars driven by the spindle motor A sewing machine main body, a binder for holding a drape on the body cloth, and a pair of presser arms that descend to both sides of the binder and press and hold the body cloth and the drape. A large presser mechanism that conveys the cloth along the cloth feeding direction, a center knife arranged downstream of the needle drop position of the two sewing needles in the cloth feeding direction, and a knife motor that raises and lowers the center knife. The center is driven by the female motor. A center knife mechanism that raises and lowers the sewing machine at a predetermined raising / lowering speed to form a linear cut between the two seams, and a back tack that has different rear end positions at the rear ends of the two seams. And a control means for controlling the spindle motor, the one-needle stop mechanism, the large presser mechanism, and the knife motor so as to form a seam and form the linear cut between the two seams. In the bead stitch sewing machine, when the control means forms the rear ends of the two stitches (P, Q), the rear end portion of the two stitches is located further downstream in the cloth feeding direction. Form the seam of the two main stitches (P1, Q1) up to the rear end of one seam (Q) and form the straight cut, then interrupt the formation of the other seam (P) The main stitching portion of the one seam Form a seam of the back tack seam (Q2) continuous to the seam of Q1), and then feed the cloth from the end position of the back tack part of the one seam to the interruption position of the other seam And then the formation of the seam of the main stitching portion (P2) is resumed from the interrupted position of the other seam and the straight cut is formed, and then the other seam is formed. The back tack seam (P3) has a seam formed continuously with the main seam of the seam, and the center knife is moved up and down at a speed lower than the predetermined lifting speed when the cloth is fed forward. The driving of the main shaft motor, the one-needle stop mechanism, the large pressing mechanism, and the female motor is controlled.
Here, the idle feed of the cloth refers to an operation of feeding the cloth without operating the needle bar, in other words, an operation of feeding only the cloth without sewing.

  According to the first aspect of the present invention, the control means decelerates the ascending / descending speed of the center knife when feeding the cloth faster than a predetermined ascending / descending speed when the center knife forms a linear cut. Since the drive of the knife motor is controlled, the number of sliding of the center knife can be reduced, and the sliding noise of the center knife and the operation noise of the center knife mechanism can be reduced. Further, since the number of sliding of the center knife is reduced, the wear amount of the center knife is reduced, and the life of the center knife can be extended.

  The invention according to claim 2 has two needle bars that hold the two sewing needles and move up and down driven by the spindle motor, and each sewing needle can be stopped individually at the raised position. The sewing machine main body includes a needle up-and-down movement mechanism having a mechanism configured as described above, and forms and stitches the body cloth and the drape into two seams by the vertical movement of the two needle bars driven by the spindle motor And a binder for holding the drapery on the cloth, and a pair of presser arms for holding the cloth and the drape down by sandwiching the binder and feeding the cloth and the drape. A large pressing mechanism that conveys along the direction, a center knife disposed downstream of the needle drop position of the two sewing needles in the cloth feeding direction, and a knife motor that raises and lowers the center knife. Drive the center knife. A center knife mechanism that forms a linear cut between the two stitches by raising and lowering at a raising and lowering speed of the two stitches, and stitches of condensed stitch portions having different rear end positions at the rear ends of the two stitches. And a control means for controlling the spindle motor, the one-needle stop mechanism, the large presser mechanism and the female motor so as to form the linear cut between the two seams. In the edge stitch sewing machine, when the control means forms the rear ends of the two stitches (R, T), the rear end position of the two stitches is located further downstream in the cloth feeding direction. The seam of the two main seams (R1, T1) is formed up to the start position of the condensed seam (T2) of one seam (T) and a straight cut is formed, and then the other seam (R Before interrupting the formation) A stitch of a condensed stitch portion (T2) that is continuous with the main stitch portion of one stitch is formed, and then the cloth is applied from the stitch end position of the condensed stitch portion of the one stitch to the interrupt position of the other stitch. Next, the formation of the seam of the main stitching portion (R2) is resumed from the position where the other seam is interrupted, and the linear cut is formed. The stitches of the condensation stitching portion (R3) continuous to the main stitching portion of the other stitch are formed, and the raising / lowering speed of the center knife is decelerated from the predetermined raising / lowering speed when the cloth is fed forward. The driving of the main shaft motor, the one-needle stop mechanism, the large pressing mechanism, and the female motor is controlled.

  According to the second aspect of the present invention, the control means decelerates the ascending / descending speed of the center knife when feeding the cloth faster than the predetermined ascending / descending speed when the center knife forms a linear cut. Since the driving of the knife motor is controlled, the number of sliding of the center knife can be reduced, and the sliding noise can be reduced. Further, since the number of sliding of the center knife is reduced, the wear amount of the center knife is reduced, and the life of the center knife can be extended.

  According to a third aspect of the present invention, in the ball stitch sewing machine according to the first or second aspect, the invention further comprises setting means for setting the number of rotations of the female motor when the cloth is fed in an idle state.

  According to the third aspect of the present invention, since the rotation speed of the knife motor when the cloth is fed idle can be set by the setting means, each user is free to the extent that the user does not care about the sliding sound of the center knife. You can slow down.

  According to the first aspect of the present invention, the control means decelerates the ascending / descending speed of the center knife when feeding the cloth faster than a predetermined ascending / descending speed when the center knife forms a linear cut. Since the driving of the knife motor is controlled, the number of sliding of the center knife can be reduced, and the sliding noise can be reduced. Further, since the number of sliding of the center knife is reduced, the wear amount of the center knife is reduced, and the life of the center knife can be extended.

  According to the second aspect of the present invention, the control means decelerates the ascending / descending speed of the center knife when feeding the cloth faster than the predetermined ascending / descending speed when the center knife forms a linear cut. Since the driving of the knife motor is controlled, the number of sliding of the center knife can be reduced, and the sliding noise can be reduced. Further, since the number of sliding of the center knife is reduced, the wear amount of the center knife is reduced, and the life of the center knife can be extended.

  According to the third aspect of the present invention, since the rotation speed of the knife motor when the cloth is fed idle can be set by the setting means, each user is free to the extent that the user does not care about the sliding sound of the center knife. You can slow down.

Hereinafter, an embodiment of a bead stitch sewing machine according to the present invention will be described.
<Overall configuration of the sewing machine>
FIG. 1 is a perspective view showing an overall schematic configuration of a bead stitch sewing machine 100. In the present embodiment, the respective directions are determined with reference to the XYZ axes shown in the drawings, and the Z-axis direction coincides with the vertical movement direction of the center knife, which will be described later, and is a plane for performing the sewing work. Is perpendicular to the Z-axis direction and is parallel to the work plane and the direction in which the cloth is fed is the X-axis direction, and the direction parallel to the work plane and perpendicular to the X-axis direction is the Y-axis direction.

As shown in FIG. 1, the edge stitch sewing machine 100 is configured to sew a cloth on a body cloth and to form a straight cut along the feeding direction of the cloth and both ends of the straight cut. A sewing machine that forms a V-shaped cut.
The bead stitch sewing machine 100 includes a needle bar mechanism 10 (see FIG. 2) that controls the operation of a sewing machine table 11 serving as a sewing work table and a pair of balances (not shown) and a needle bar 20 that holds a sewing needle 20a. A sewing machine body 12 that forms two seams on the cloth and the ball cloth by the vertical movement of the bar 20, a large presser mechanism 1 as a cloth feed mechanism that feeds the cloth made of the cloth and the ball cloth, A binder 2 that holds the top cloth from above and a center knife 301 that is supported by the sewing machine body 12 and that is disposed downstream of the sewing needle 20a in the cloth feeding direction is moved up and down in the middle of the sewing needles to straighten each cloth. Center knife mechanism 3 (see FIG. 10) for forming a line-shaped cut, a corner knife mechanism 9 for forming a substantially V-shaped cut at positions corresponding to both ends of the straight cut, and a control means for controlling each of the above parts As a system It includes a device 5 (see FIG. 11), the.

(Needle bar mechanism)
As shown in FIGS. 2 to 8, the needle bar mechanism 10 is provided inside the front end of the sewing machine main body 12, and simultaneously or paired with a pair of needle bars 20 and 20 that individually hold the two sewing needles 20 a and 20 a. It is selectively moved up and down.

  As shown in FIG. 2, the needle bar mechanism 10 includes a pair of needle bars 20, a needle bar support frame 40 as a needle bar support that individually supports each needle bar 20 so as to be movable up and down, and a pair of needle bars. A pair of needle bars up and down mechanism 50 that moves each needle bar 20 up and down using needle bar holders 51 that individually hold 20, and a pair that inserts and removes the tip with respect to the first engagement hole 21 of each needle bar 20. A clutch mechanism 60 that can selectively switch the holding of each needle bar 20 by the needle bar holder 51 between the holding state and the released state using the clutch member 61 of FIG. 5, and the clutch mechanism 60 as shown in FIG. 2 and 5, a stopper mechanism 70 that holds the needle bar support frame 40 using a stopper member 71 that inserts and removes the tip of the needle bar 20 in the released state from the second engagement hole 22 of the needle bar 20. As shown, select one of the needle bars 20 in the clutch mechanism 60. A holding release switching mechanism 80 for switching the released state and the holding state, and a. The clutch mechanism 60, the stopper mechanism 70, and the hold release switching mechanism 80 constitute a one-needle stop mechanism 120 that can individually stop the sewing needles 20 and 20 at the raised position.

(Needle bar)
As shown in FIGS. 2 to 5, each needle bar 20 is normally supported by the needle bar support frame 40 in a state along the Z-axis direction. A rotation and swinging motion is applied about an axis along the Y-axis direction at an intermediate position in the longitudinal direction of each needle bar 20. When such swinging is performed, the upper and lower ends of each needle bar 20 swing along the X-axis direction.

Each needle bar 20 is a bar-shaped body in which a flat surface 23 is formed on a part of the circumferential surface of a round bar having a circular cross section, and the sewing needle 20a is held at the lower end portion thereof.
In a state where the needle bar 20 is supported along the Z-axis direction, the flat surface 23 is supported by the needle bar support frame 40 so as to be in a state along the YZ plane. A groove portion 24 is formed along the longitudinal direction at the intermediate position in the Z-axis direction on the flat surface 23.

Further, a first engagement hole 21 and a second engagement hole 22 are formed on the flat surface 23 in the vicinity of the lower end and the upper end of the groove 24 so as to overlap the groove 24. Has been.
The first engagement hole 21 is formed in a rectangular shape corresponding to the tip shape so that the tip portion of the clutch member 61 can be inserted. Such a rectangular shape corresponds to the front end portion of the clutch member 61 protruding in a substantially rectangular shape, and the length of the long side and the short side of the rectangle are the width of the front end portion of the substantially rectangular shape of the clutch member 61, respectively. It is set slightly larger than the vertical width.
The second engagement hole 22 is positioned above the first engagement hole 21 and has a rectangular shape in front view corresponding to the shape of the tip of a stopper member 71 (see FIG. 5) described later. And formed in a semicircular shape when viewed from the side.

An oscillating plate 25 is swingably attached to the inside of the groove portion 24 along the longitudinal direction of the groove portion 24. The swing plate 25 is supported by a support shaft along the Y-axis direction at an intermediate position between the first engagement hole 21 and the second engagement hole 22, and both ends of the swing plate 25 are X-axis by swinging. Move along the direction. That is, one end and the other end of the swing plate 25 move along the depth direction of each of the engagement holes 21 and 22 in the first engagement hole 21 and the second engagement hole 22, respectively. Do.
Further, when one end of the swing plate 25 is pushed into the vicinity of the deep portion of the first engagement hole 21, the other end is pushed out to the flat surface 23 in the second engagement hole 22, and the other end is pushed. When pushed into the vicinity of the deep portion of the second engagement hole 22, one end portion is formed into a shape that is pushed out to the flat surface 23 in the first engagement hole 21.
That is, for the same needle bar 20, when the clutch member 61 is inserted into the first engagement hole 21, the stopper member 71 that has already been inserted into the second engagement hole 22 is pushed out by the swing plate 25. . When the clutch member 61 is inserted into the second engagement hole 22, the clutch member 61 that has already been inserted into the first engagement hole 21 is pushed out by the swing plate 25.

  Further, when the needle bar 20 moves up and down, the needle bar 20 is engaged with the clutch mechanism 60 through the first engagement hole 21 and held by the needle bar holder 51. On the other hand, when the vertical movement is stopped for sewing with one needle, the clutch mechanism 60 is released and the second engagement hole 22 is engaged with the stopper mechanism 70 to hold the needle bar support frame 40.

(Needle bar support frame)
As shown in FIGS. 2, 4, and 7, the needle bar support frame 40 is formed with insertion holes through which the two needle bars 20 are arranged in the Y-axis direction at the upper and lower parts thereof. The needle bar 20 is supported so as to be movable up and down.
In the vicinity of the support portion of the needle bar 20 at the lower portion of the needle bar support frame 40, a supply member 41 such as a nonwoven fabric or urethane to which lubricating oil or grease is supplied is provided, and slides on the supply member 41. Each needle bar 20 is arranged as described above. Thereby, lubricating oil or grease is supplied to the sliding part of each needle bar 20 and the needle bar support frame 40, and the vertical movement is performed smoothly.

A stopper mechanism 70 is provided in the vicinity of the support portion of the needle bar 20 above the needle bar support frame 40, and a holding release switching mechanism 80 is provided immediately below the stopper mechanism 70 of the needle bar support frame 40. It has been. The stopper mechanism 70 and the holding release switching mechanism 80 will be described in detail later.
Further, in the vicinity of the needle bar 20 supported by the needle bar support frame 40, vertical movement of a square piece 55 provided at one end of a link body 54 that applies a driving force for vertical movement to each needle bar 20. A guide groove 42 for guiding the above is formed.

  In addition, one end of a swing shaft 43 that applies a swing driving force for swinging the needle is connected to an intermediate position in the vertical direction at one end of the needle bar support frame 40 in the Y-axis direction. The swing shaft 43 is supported by the sewing machine frame so as to be rotatable along the Y-axis direction, and is connected to a swing mechanism that swings in synchronization with the vertical movement of the needle bar 20. Further, the swing mechanism can adjust the swing angle range from 0 to a predetermined angle range by a well-known configuration, and if necessary, the sewing needles held by the needle bars 20 can be moved along the X-axis direction. It is possible to swing the needle with an arbitrary swing width. That is, the swing mechanism functions as a needle swing mechanism. Further, as described above, the swing mechanism of the needle swing is adjusted so that each needle bar 20 is in a state along the Z-axis direction when the needle swing is not performed.

(Needle vertical movement mechanism)
As shown in FIG. 4, the needle vertical movement mechanism 50 is rotationally driven by a needle bar holder 51 that supports each needle bar 20 via a clutch mechanism 60 and a spindle motor 101 that is a vertical movement drive source of each needle bar 20. Sewing machine main shaft 52, rotary weight 53 fixedly attached to one end of the sewing machine main shaft 52, link body 54 connecting the rotary weight 53 and needle bar holder 51, and the needle bar holder side of link body 54 And a square piece 55 for moving the end portion along the Z-axis direction. The spindle motor 101 is, for example, an AC servomotor that can be rotated forward and backward. In the following description, the rotation direction of the motor shaft when the spindle motor 101 is driven is not particularly described. Is driven in a positive rotation that rotates the sewing machine main shaft 52 in the positive direction.

(Clutch mechanism)
As shown in FIGS. 2 and 4 to 7, the clutch mechanism 60 includes two clutch members 61 inserted into a circular support hole 57 penetrating from the front surface of the needle bar holder 51 to each insertion hole, and each clutch member 61. The two driven links 62 that individually move forward and backward respectively, the two pressing springs 63 that individually apply the moving force in the forward direction to the clutch members 61 via the driven links 62, and the clutch members 61, respectively. Two locking claws 64 that are respectively locked in the retracted state (retracted position), two pressing springs 65 that are respectively pressed in the direction in which each locking claw 64 is locked, and locking by each locking claw 64 And a release pin 66 capable of inputting an operation for releasing from the outside.
Here, as shown in FIGS. 5 and 7, the two driven links 62 are formed so as to be bent near the central portion in the longitudinal direction, and the bent portion P is rotatably attached to the needle bar holder 51. . One end of the driven link 62 is connected to the clutch member 61.
Then, as shown in FIG. 7, the driven link 62 is pushed down from above and rotates in the A direction with the bent portion P as a fulcrum, whereby one end of the driven link 62 pulls the clutch member 61, The engagement of the needle bar 20 corresponding to the clutch member 61 with respect to the needle bar holder 51 can be released by retreating from the one engagement hole 21 and being engaged with the respective locking claws 64.
Further, as shown in FIG. 5, the release pin 66 is pushed down from above and the engagement of the clutch member 61 by the engagement claw 64 is released, so that the clutch member 61 is urged by the pressing spring 63 to be in the first state. The needle bar 20 can be engaged with the needle bar holder 51 by moving forward toward the engagement hole 21.

(Holding release switching mechanism)
2 and 5-7, the holding release switching mechanism 80 includes a guide groove 82 formed in the needle bar support frame 40 at a position slightly above the top dead center of the needle bar holder 51, and a guide The switching member 81 is slidably supported along the groove 82, and the pressing cover 83 prevents the switching member 81 from falling off the guide groove 82.
The guide groove portion 82 is formed along the Y-axis direction in the upper portion of the needle bar support frame 40, and supports the switching member 81 so as to be slidable along the same direction.

The switching member 81 has a substantially prismatic shape as a whole, an abutting projection 81a projecting in a direction perpendicular to the longitudinal direction is formed at one end, and the other end is an air provided outside the machine frame. The cylinder is connected to a solenoid valve 90 (see FIG. 10).
Specifically, an electromagnetic valve 90 of an air cylinder is connected to the control device 5 via a driver 90a. As the air cylinder, a three-position type air cylinder having two electromagnetic valves 90 in the cylinder is used. The position of the switching member 81 connected to the electromagnetic valve 90 can be switched to three positions by controlling the driving of the two electromagnetic valves 90 in the cylinder by the control device 5. Thereby, it can switch to three sewing of a left needle, both needles, and a right needle.

In addition, not only an air cylinder but a solenoid may be used. Specifically, two solenoid plungers may be connected to the switching member 81 and the two solenoids may be individually controlled by the control device 5. That is, the type of the drive source is not limited as long as the drive of the switching member 81 can be electrically controlled.
The switching member 81 is supported by the guide groove portion 82 in a state where the contact protrusion 81a is directed downward. Then, the movement of the switching member 81 along the Y-axis direction pushes one of the driven links 62, the other driven link 62, or the release pin 66 of the clutch mechanism 60 when the needle bar holder 51 reaches the top dead center. The contact protrusion 81a can be switched to a possible position. The contact protrusion 81a is pushed downward by the stroke required for each release or engagement operation with respect to each driven link 62, 62 and release pin 66 of the needle bar holder 51 that has been raised to the top dead center position. It is set to the possible protrusion length.

(Stopper mechanism)
As shown in FIGS. 5 and 7, the stopper mechanism 70 is a support having two circular through holes penetrating from the front surface of the needle bar support frame 40 to the insertion hole of the needle bar 20 at the upper end portion of the needle bar support frame 40. Part 72, two stopper members 71 inserted into the through holes of each support part 72, and two pressing springs 73 that individually impart a moving force in the forward direction (needle bar 20 side) to each stopper member 71, And a cover body 74 that supports each pressing spring 73 at the rear and covers and closes the through hole of the support portion 72.

(Sewing table and sewing machine body)
As shown in FIG. 1, the sewing machine table 11 is used in a horizontal state with its upper surface parallel to the XY plane. The upper surface of the sewing machine table 11 is formed in a long rectangular shape along the cloth feeding direction F, that is, the X-axis direction. A large presser mechanism 1 and a binder 2 are disposed on the sewing table 11, and a corner knife mechanism 9 is disposed below the sewing table 1.
A needle plate 13 is provided at a position below the two sewing needles 20a, 20a in the sewing machine table 11. The needle plate 13 is provided with a needle hole corresponding to each of the two sewing needles 20a, 20a, and a horizontal hook (not shown) is provided below each needle hole.
That is, the sewing thread inserted through each of the sewing needles 20a and 20a is captured by the corresponding horizontal hook at the lower side of the needle plate 13, and is entangled with the lower thread fed out from the horizontal hook. It is like that.
Furthermore, a slit into which the center knife 301 is inserted is formed in the middle of the two needle holes of the needle plate 13 and downstream in the cloth feeding direction F, and the cloth is cut in cooperation with the center knife 301. A fixed knife is not placed. This fixed knife constitutes the center knife mechanism 3.

  The sewing machine main body 12 is arranged along the Y-axis direction from the bed portion 12a arranged immediately next to the intermediate position in the longitudinal direction of the sewing machine table 11, the vertical body portion 12b erected from the bed portion 12a, and the upper end portion of the vertical body portion 12b. The arm part 12c is extended, and the main components of the needle vertical movement mechanism 40 and the moving knife mechanism are stored in the arm part 12c. Further, the two needles 20a, 20a and the center knife 301 are supported in a suspended manner from the lower end portion on the distal end side of the arm portion 12c.

(Large holding mechanism)
The large presser mechanism 1 includes large pressers 15 and 15 for pressing each of both ends in the width direction of the ball set set on the binder 2, a support body 16 for supporting these large pressers 15 and 15, and a support body 16. The main shaft motor 101 moves the large pressers 15 and 15 up and down via an air cylinder (not shown) and the cloth and cloth pressed by the large pressers 15 and 15 in the cloth feed direction F via the support 16. And a separate pressing motor 102.
Each of the large pressers 15 and 15 is a rectangular flat plate, and each of the large pressers 15 and 15 is supported by the support 16 in a state where the longitudinal direction is along the X-axis direction. The large pressers 15 and 15 are supported so that the flat plate surfaces thereof are parallel to the XY plane. Then, it can be switched to two upper and lower positions by driving the air cylinder. When the air cylinder is in the upper position, it is separated from the upper surface of the sewing machine table 11 and becomes the upper surface height of the sewing machine table 11 at the lower position. Further, the two large pressers 15 and 15 are supported in a state of being separated so that at least the standing plate portion 32 of the binder 2 can be passed therebetween.
The support 16 is supported on the sewing machine table 11 so as to be movable along the X-axis direction, and the two large pressers 15 and 15 to be supported pass through both sides of the vertical movement path of the two needles 20a and 20a. Is arranged. The support 16 is driven by the pressing motor 102 via a ball screw mechanism (not shown).

(binder)
As shown in FIGS. 1 and 9, the binder 2 includes a bottom plate portion 31 that is an elongated flat plate, a standing plate portion 32 that is erected vertically on the upper surface along the longitudinal direction of the bottom plate portion 31, and a standing plate. The guide member 33 that guides the ball cloth B while avoiding the center knife 301 and the both end portions in the width direction of the ball cloth are fed along both surfaces of the upright plate portion 32 to the downstream end portion of the cloth portion 32 in the cloth feed direction. And a vertical guide portion 34 for guiding as described above.
The binder 2 is supported by a support mechanism (not shown) including an air cylinder, and is retracted away from the position below the two sewing needles 20a and 20a when not in use, as shown in FIG. And in use, it is set to the needle plate position by driving the air cylinder.

The bottom plate portion 31 is formed in a rectangular shape, and is supported so that, when in use, the longitudinal direction thereof is parallel to the X-axis direction and the bottom surface thereof is placed facing the upper surface of the sewing machine table 11. ing. Further, substantially U-shaped cutouts 31a and 31a are formed at the front end portion of the bottom plate portion 31 in the cloth feeding direction as grooves for allowing the two sewing needles 20a and 20a to drop needles, respectively.
The standing plate part 32 is a flat plate having a rectangular shape as a whole except for a portion in the vicinity of the guide member 33. It is erected vertically with the bottom plate portion 31 aligned with the longitudinal direction. That is, the binder 2 is integrally formed so that the bottom plate portion 31 and the upright plate portion 32 have an inverted T shape when viewed from the longitudinal direction.

  Then, when the bedcloth is set on the needle plate 13 so as to overlap the upper side of the cloth, the binder 2 is placed from above, and both ends in the width direction of the ball cloth are folded back so that both ends in the width direction of the bottom plate portion 31 are placed. It is held up by the large pressers 15 and 15 so that both ends in the width direction of the ball cloth are along the side surfaces on both sides of the upright plate portion 32 respectively. That is, it is in a state in which the ball cloth is placed from one side surface of the standing plate portion 32 to the other side surface 32 through the bottom plate portion 31. In this way, in a state where the ball 2 is set to be wound around the binder 2, sewing is performed with the two sewing needles 20 a and 20 a on both sides of the standing plate portion 32 while feeding the ball and the cloth, and the center knife 301. A straight cut is formed by raising and lowering.

  As described above, two flat plates are provided at both ends in the width direction of the ball so as to be close to and opposite to both side surfaces of the upright plate portion 32 so as to maintain a state along both side surfaces of the upright plate portion 32. Shaped vertical guide portions 34, 34 are provided. Each of the vertical guide portions 34 is bent so that a gap with the upright plate portion 32 is enlarged at the upstream end portion in the cloth feeding direction, and a constant gap is maintained on the downstream side. That is, one end in the width direction of the ball cloth is introduced into the gap between each vertical guide portion 34 and the upright plate portion 32, and the one end portion is guided so as to maintain a state along one side surface of the upright plate portion 32. It is supposed to be.

  A center knife 301 is disposed on the extended line of the upright plate portion 32 immediately downstream of the binder 2 in the cloth feeding direction F. Since both end portions in the width direction of the ball cloth move to the downstream side in the cloth feeding direction F along the standing plate portion 32, the guide members 33 are provided so as not to be torn by the center knife 301. The guide member 33 is integrally formed from the downstream end portion of the standing plate portion 32 in the cloth feeding direction F, and is bifurcated in the cloth feeding direction F so that the shape in plan view is substantially V-shaped. It forms so that it may become a shape. And the guide member 33 is arrange | positioned so that the center knife 301 may be covered as close as possible with respect to the center knife 301, and the center knife 301 may be covered from both sides, in order to guard a drape from the center knife 301 more effectively. With this shape, both ends in the width direction of the ball cloth are guided in the direction away from the upright plate portion 32 through the gap between the vertical guide portion 34 and the guide member 33 when the fabric is fed. It is guided in the direction to avoid.

(Center knife mechanism)
FIG. 10 is a perspective view of the needle bar up-and-down moving mechanism 50 and the center knife mechanism 3 in a severable state.
The center knife mechanism 3 includes a center knife 301 that forms a linear cut by an elevating operation, a fixed knife (not shown) that is fixed below the needle plate 13 and that slides on the center knife 301 to promote cutting of the fabric. A knife rod 302 provided with a knife 301 at the lower end and supported so as to be slidable along the Z-axis direction in the arm 12c, a knife motor 303 that is a stepping motor that moves the center knife 301 up and down, and an output of the knife motor 303 A plurality of link bodies 305 that transmit the vertical movement driving force to the knife rod 302 via the eccentric cam 304 that is mounted eccentrically with respect to the shaft 303b, and the center knife 301 in a severable state (lower position) and a cutting restriction state ( An air cylinder 306 as an actuator serving as a drive source for the switching operation with respect to the upper position), The plunger digi a stopper 307 for stopping at a predetermined position, and a.

When the air cylinder 306 is in the retracted position (the state shown in FIG. 10), the center knife mechanism 3 is in a severable state in which the rotational driving force of the knife motor 303 is converted into a vertical reciprocating motion to the center knife 301 and transmitted. When the cylinder 306 is in the forward position (not shown), it is possible to switch to a cutting restriction state in which the rotational driving force of the knife motor 303 is not transmitted to the center knife 301.
When the knife motor 303 is driven to rotate while the air cylinder 306 is retracted, the knife rod 302 and the center knife 301 are connected via a plurality of link bodies 305 by the eccentric cam 304 mounted on the output shaft 303b oriented in the Y-axis direction. The cutting operation is performed by moving up and down.
On the other hand, when the air cylinder 306 is in the advanced state, the plurality of link bodies 305 are arranged so that the power of the female motor 303 cannot be transmitted to the female bar 302, and the center knife 301 is retracted above the needle plate 13. State is maintained.
Accordingly, the air knife 306 is driven so that the center knife 301 can be switched between a cutting-capable state and a cutting restriction state.
In addition, the raising / lowering speed when the center knife 301 cuts the cloth to form a linear cut is set in advance to a predetermined raising / lowering speed corresponding to the cloth feeding speed by the large pressing mechanism 1 and stored in the ROM 152 described later. The female motor 303 is driven to rotate at a speed corresponding to the ascending / descending speed stored in the ROM 152.

(Corner knife mechanism)
As shown in FIG. 1, the corner knife mechanism 9 is disposed below the sewing machine table 11 and in the passage of the large pressers 15, 15 by the large presser mechanism 1, and the balls conveyed by the large presser mechanism 1. By cutting the corner knife 91 through the edge cloth and the body cloth from below, a substantially V-shaped cut is formed at the positions corresponding to both ends of the straight cut.
That is, the corner knife mechanism 9 includes two corner knives 91 and 91 arranged at intervals along the cloth feeding direction F, and a vertical movement motor (not shown) that moves the corner knives 91 and 91 up and down, respectively. ing.

Each corner knife 91 is composed of a pair of triangular knives arranged so that the shape seen from the distal end side is V-shaped, and is supported with the distal end portion facing upward. And by moving up and down from the upper surface of the sewing machine table 11 by the vertical movement motor, it is possible to form a V-shaped cut in the fabric. Each corner knife 91 can adjust the angle between a pair of triangular knifes, and can correspond to the interval between two stitches by the two sewing needles 20a, 20a.
The two corner knives 91 are supported so that the openings of the V-shaped cuts formed by the two corner knives 91 are opposite to each other. The interval between the two corner knives 91 can be adjusted.

  The corner knife mechanism 9 has two corner knife 91, when the fabric formed with two stitches and a linear cut is conveyed by the large pressing mechanism 1 to a position directly above the corner knife mechanism 9. Two V-shaped cuts are formed in the fabric by moving 91 up and down at each end position of the cut. That is, by the corner knife mechanism 9, one end cut from one end of the straight cut to the closest end of each of the two seams, and the other of the straight cut Another cut is formed from the end to the closest end of each of the two seams.

(Control device)
As illustrated in FIG. 11, the control device 5 includes a display panel 84 that displays information on predetermined characters or images to be notified to the user, and screen selections and commands for performing various settings provided in the display panel 84. An input / output circuit (not shown) is provided with a setting switch 85 for inputting, a numeric keypad 86 for inputting numerical values when inputting various settings and determining or canceling the setting, and a start switch 87 for inputting the start of sewing. Connected through. Here, the setting switch 85 and the numeric keypad 86 function as setting means for setting the number of rotations of the female motor 303 when the fabric is fed idle.

  In addition, a spindle motor 101, a presser motor 102, and a female motor 303, which are the control targets, are connected to the control device 5 via drivers 101a, 102a, and 303a, respectively. In addition, an air cylinder for moving the binder 2 up and down, an air cylinder for moving the large pressers 15 and 15 up and down, and motors for vertical movement (not shown) for moving up and down the corner knives 91 and 91 are connected to the control device 5 via a driver. It is connected. In addition, an electromagnetic valve 308 of an air cylinder 306 that switches between an operating state and a non-operating state of the center knife 301 is connected via a driver 308a. Further, a needle swing motor 105 coupled to the swing shaft 43 is connected to the control device 5 via a driver 105a in order to swing the sewing needles 20a and 20a. Further, an electromagnetic valve 90 of an air cylinder for changing the position of the switching member 81 is connected to the control device 5 via a driver 90a.

The control device 5 includes a CPU 151 that performs various arithmetic processes, a ROM 152 in which control programs, control data, or various sewing data for executing various functions and operations (described later) of the edge stitch sewing machine 100 are written, and the CPU 151 A RAM 153 for storing various data related to processing in the work area is provided.
In the ROM 152, when the rear end of the two seams is formed, the rear end of the two seams P and Q is further transferred to the rear end n3 of one of the seams Q located further downstream in the cloth feeding direction. The seam of the main seam portion P1, Q1 of the book is formed and a straight cut is formed by the center knife 301. Next, the formation of the other seam P is interrupted, and the seam of the main seam portion Q1 of one seam Q is interrupted. The back tack seam Q2 is continuously formed, and then the seam end position n6 of the back tack part Q2 of the seam Q to the interruption position of the other seam P (the back tack seam of the other seam P) The starting position of the seam of the portion P2 is fed to the downstream side in the cloth feeding direction to n3, and then the middle stitch position n3 of the other seam P (continuous to the main sewing portion P1) of the main sewing portion P2 When we resume the formation of seams A straight cut is formed, and then a seam of the back tack seam P3 that is continuous with the main seam P2 of the other seam P is formed, and the end position of the seam of the back tack part Q2 of the seam Q is described above. The spindle motor 101 and the one-needle stop mechanism 120 are arranged so that the vertical movement speed of the center knife 301 is decelerated from the vertical movement speed at the time of forming the linear cut when the cloth is fed from n6 to the interruption position n3 of the other seam P. A control program for controlling the driving of the large pressing mechanism 1 and the female motor 303 is stored.
That is, when the CPU 151 executes the control program, the control device 5 functions as a control unit.
Note that the seam of the back tack seam here is the seam that forms the seam over the seam that has already been formed or the cloth feed direction is the reverse direction (the direction opposite to the arrow F direction in FIG. 1). The seam of the main stitch portion is a so-called normal seam that forms a seam by feeding the cloth in the normal cloth feed direction (the direction of arrow F in FIG. 1). In order to distinguish from the seams of the back tack seams Q2, P2, they are referred to as the seams of the main seam.

<Back seam stitch forming method>
Next, referring to FIG. 12 and FIG. 13, the back-tack in which the positions (rear end positions) of the rear end portions n3 and n8 are different from each other at the rear ends of the two stitches P and Q by the edge stitch sewing machine 100. A seam forming method when forming the seams of the seams Q2 and P3 will be described.
When an operator presses a sewing start switch or the like, the CPU 151 of the control device 5 executes a control program to control the driving of the main shaft motor 101, the electromagnetic valve 90 of the air cylinder, and the large presser mechanism 1, and thereby the stitches. At the same time, the center knife 301 is moved up and down by driving the air cylinder 306 and the knife motor 303 to form a straight cut between the two stitches P and Q. In addition, the raising / lowering speed of the center knife 301 at the time of formation of this linear cut | interruption is driven by the predetermined raising / lowering speed set and memorize | stored with respect to the fabric feed speed by the large pressing mechanism 1, as mentioned above. In the following description, the edge stitch sewing machine 100 is a double needle in which both needle bars 20 and 20 are always engaged with the needle bar holder 51 when the power is turned on for the first time or at the end of a predetermined edge stitch. In the following description, it is assumed that the sewing machine is in a state where it can be sewn.

As shown in FIGS. 12 and 13, when the CPU 151 executes the control program, first, the CPU 151 drives the solenoid valve 90 of the air cylinder to move the switching member 81, and moves the two sewing needles 20a and 20a up and down. It moves to a position where it can move (step S21).
At this time, the CPU 151 drives the solenoid valve 90 of the air cylinder to move the switching member 81 so that the contact protrusion 81a is positioned above the driven link 62 provided on both needle bars 20. .

Next, the CPU 151 determines whether or not the formation of one of the seams (P1, Q1) of both the seams (P, Q) is completed, that is, two seams (P, Q). ) Is determined whether the rear end portion is located further downstream in the cloth feeding direction (step S22). This determination may be made at the end of formation of the stitches of the main stitch portions (P1, Q1) as in the present embodiment, but each portion of the preset stitches (P, Q) is preset. It may be determined from the sewing length data. Here, when the CPU 151 determines that the formation of any stitches of the main stitch portion (P1, Q1) has not been completed (step S22: NO), the CPU 151 drives the spindle motor 101 and the large presser mechanism 1. As a result, the stitches of the main stitch portions (P1, Q1) of both the stitches (P, Q) currently being formed are formed, and the center knife 301 is moved up and down by driving the knife motor 303, thereby forming a linear cut line. Is formed (step S23).
Here, when forming the stitches of the main stitch portions P1, Q1 of both the stitches P, Q, the stitches are formed by dropping the needles in the order of the needle drop positions n0, n1, n2, n3.

Then, the CPU 151 continues the formation of the stitches in the main stitch portion (P1, Q1) until it is determined that the formation of any one of the stitches in the main stitch portion (P1, Q1) has been completed.
In step S22, when the CPU 151 determines that the formation of any seam of the main stitch portion (P1, Q1) has been completed (step S22: YES), the CPU 151 drives the solenoid valve 90 of the air cylinder to Only the needle bar 20 (right side) involved in the formation of one seam (Q) whose rear end portion is located further downstream in the cloth feeding direction is driven. Therefore, the switching member 81 is moved so that the contact protrusion 81a is positioned above the driven link 62 provided on the other needle bar 20 (left side) to be stopped by the contact protrusion 81a of the switching member 81. While the sewing needle 20a can be moved up and down, the formation of the seam by the other sewing needle 20a is interrupted, and the sewing can be performed with only one sewing needle 20a (step S24).

Next, the CPU 151 determines whether or not the formation of the seam of the back tack seam (Q2) of the one (right) seam (Q) has been completed (step S25). Here, when the CPU 151 determines that the formation of the seam of the back tack stitch portion (Q2) of one seam (Q) has not been completed (step S25: NO), the CPU 151 determines the spindle motor 101 and the presser motor 102. , By driving one sewing needle 20a up and down while transporting the cloth to the upstream side in the cloth feeding direction via the large presser mechanism 1, the seam of the back tack seam (Q2) of one seam (Q) Is formed (step S26).
Here, when forming the seam of the back tack seam Q2 of one seam Q shown in FIG. 12, it is formed by causing needle drop in the order of needle drop positions n3, n4, n5 and n6.
Then, the CPU 151 continues the seam formation of the back tack seam (Q2) until it is determined that the seam of the back tack seam (Q2) has been formed.

In step S25, when the CPU 151 determines that the formation of the seam of the back tack stitch portion (Q2) has been completed (step S25: YES), the CPU 151 determines the sewing needle to be used from one sewing needle 20a (right needle). Switch to the other sewing needle 20a (left needle).
Here, when the sewing needles 20a, 20a used for sewing are switched from one needle (right needle) to one needle (left needle), they cannot be switched at a time, so switching is performed according to the following procedure.
The CPU 151 drives the solenoid valve 90 of the air cylinder as soon as the one sewing needle 20a (right needle) starts to rise from the final needle drop point (n6) of the one of the back tack stitches, so that the switching member 81 is contacted. The contact protrusion 81a is moved above the release pin 66, and the two sewing needles 20a and 20a can be moved up and down by the advancement of the clutch member 61 when the needle bar 20 reaches the top dead center. (Step S27).

Then, when the pair of balances (not shown) of the sewing machine body 12 reaches the top dead center, the CPU 151 stops the driving of the respective parts such as the spindle motor 101 and temporarily suspends the sewing (step S28).
At this time, the CPU 151 decelerates the female motor 303 so that the number of rotations is set in advance by the setting switch 85 and the numeric keypad 86 (step S29). Thereby, CPU151 decelerates the raising / lowering speed of the center knife 301 until it becomes a predetermined speed slower than the raising / lowering speed at the time of the linear cut formation mentioned above. This is because the center knife 301 is not stopped even during idle feeding in order to stabilize the drive. Therefore, when the cloth is not cut, the number of times the center knife 301 and the fixed knife slide is reduced as much as possible. This is to reduce noise generated during sliding and prevent wear of each knife.
Next, after reducing the rotational speed of the female motor 303, the CPU 151 finishes the formation of the seam of the back tack seam (Q2) of one seam (Q), and the needle drop position does not move up and down without moving the needle up and down. The large presser mechanism 1 is driven so as to reach the interruption position (n3) in the formation of the stitch (P) on the (left side), and the cloth is fed downstream in the feed direction (cloth feed in the F direction in FIG. 12) ( Step S30: Skip feed step).

Next, the CPU 151 switches the sewing needles 20a, 20a used for sewing from both needles to the other one needle (left needle) (step S31).
When switching from both needles to one needle (left needle), the CPU 151 stops one of the two sewing needles 20a, 20a (right needle) upward, so that the solenoid valve of the air cylinder After moving the switching member 81 so that the contact protrusion 81a is positioned above the driven link 62 provided on the needle bar 20 of one sewing needle 20a (right needle) to be driven and stopped 90, The spindle motor 101 is stopped in a state where the spindle motor 101 is rotated in the reverse direction so that the contact protrusion 81a is brought into contact with the driven link 62 and the driven link 62 is pushed down. Thereby, the clutch member 61 corresponding to the needle bar 20 of one sewing needle 20a (right needle) is retracted, and the sewing needles 20a, 20a used for sewing are switched from both needles to one needle (left needle).
Next, the CPU 151 accelerates the reduced rotational speed of the female motor 303 to the rotational speed before the deceleration (step S32). Thereby, the preparation for the formation of the seam and the cut is completed again.

Here, transition of the rotational speed of the knife motor 303 will be described. As shown in FIG. 14, the knife is driven at a rotational speed set in advance corresponding to the cloth feed speed until it is decelerated in step S29. Then, when a command signal to decelerate is received from the control device 5 in step S29, the decelerating is started, and at the time of idle feeding in step S30, the decelerating speed is lower than the elevating speed at the time of forming the linear cut. Continue driving.
In step S32, a command signal for returning to the rotational speed before the cloth is idled is transmitted again from the control device 5 to the knife motor 303, and driving is performed at the original rotational speed immediately after the idle feeding is completed.

Next, the CPU 151 determines whether or not the formation of the seam of the main seam (P2) of the other seam (P) has been completed (step S33). Here, when the CPU 151 determines that the formation of the seam of the main seam (P2) of the other seam (P) has not been completed (step S33: NO), the CPU 151 causes the spindle motor 101 and the presser motor 102 to move. By driving, the other sewing needle 20a is moved up and down while conveying the cloth downstream in the cloth feeding direction via the large presser mechanism 1, and the interruption position (n3) for forming the other (left side) seam (P). Then, the formation of the seam of the main stitch portion (P2) is resumed, and the formation of the linear cut by the center knife 301 is resumed (step S34).
Here, when forming the seam of the main stitch portion P2 of the other seam P shown in FIG. 12, it is formed by causing needle drop in the order of the needle drop positions n3, n7, and n8.
Then, the CPU 151 continues the formation of the seam of the main stitch portion (P2) until it is determined that the formation of the seam of the main stitch portion (P2) has been completed.

In step S33, when the CPU 151 determines that the formation of the seam of the main stitch portion (P2) has been completed (step S33: YES), the CPU 151 determines the back tack stitch portion (P3) of the other (left side) seam (P). It is determined whether or not the formation of the seam has been completed (step S35). Here, when the CPU 151 determines that the formation of the stitches of the back tack stitch portion (P3) is not completed (step S35: NO), the CPU 151 drives the spindle motor 101 and the pressing motor 102 to increase the size of the stitches. The other sewing needle 20a is moved up and down while conveying the cloth upstream in the cloth feeding direction via the presser mechanism 1, thereby forming the seam of the back tack stitch portion (P3) of the other seam (P) (step S36). .
Here, when the seam is formed at the back tack seam P3 of the other seam P shown in FIG. 12, it is formed by needle dropping in the order of the needle drop positions n8, n9, n10, n11.

Then, the CPU 151 continues the seam formation of the back tack seam (P3) until it is determined that the seam of the back tack seam (P) has been formed.
In step S35, when the CPU 151 determines that the formation of the seam of the back tack seam (P3) of the other seam (P) has been completed (step S35: YES), the CPU 151 feeds the cloth by the large presser mechanism 1. The process is stopped with this.

<Effect>
According to the bead stitch sewing machine 100, the control device 5 controls the driving of the main shaft motor 101, the solenoid valve 90 of the air cylinder, the large presser mechanism 1, and the female motor 303 by the CPU 151, thereby controlling the two stitches P and Q. When forming the rear end, the rear end portion of the two seams P and Q forms the seam of the main stitch portions P1 and Q1 up to the rear end portion of one of the stitches located further downstream in the cloth feeding direction. A straight cut is formed, and then the formation of the other seam is interrupted to form the seam of the back tack seam Q2 that is continuous with the seam of the main seam Q1 of one seam Q, and then the one seam From the end position of the back tack seam of the second seam to the interrupt position of the other seam, the cloth is fed in the downstream direction in the cloth feed direction, and then the main stitch part P2 from the interrupt position of the other seam P Seams The formation is resumed and a straight cut is formed. Next, the seam of the back tack seam P3 that is continuous with the main seam P2 of the other seam P is formed, and the center knife is used when the cloth is fed forward. The lifting speed of 301 is reduced.
Thereby, since the control apparatus 5 controls the drive of the knife motor 303 so that the raising / lowering speed of the center knife 301 is decelerated when the cloth is fed idle, the number of sliding of the center knife 301 can be reduced, Sliding noise can be reduced. Moreover, since the frequency | count of sliding of the center knife 301 reduces, the wear amount of the center knife 301 reduces and the lifetime of the center knife 301 can be extended.

<Condition seam formation method>
The present invention is not limited to the back tack sewing of the above embodiment. For example, the condensed stitch portion may be formed at the stitches at the end of sewing by the method shown in FIGS. Next, referring to FIG. 15 and FIG. 16, the seam when forming the seams of the condensed seams T2, R3 where the positions of the rear ends w6, w13 are different from each other at the rear ends of the two seams R, T. A forming method will be described.
Specifically, when forming the rear ends of the two seams R and T, the start of the condensed seam of one of the two seams T where the rear end is located further downstream in the cloth feed direction The seam of the two main stitches R1 and T1 is formed up to the position w1 and a straight cut is formed. Next, the formation of the other seam is interrupted and continuous with the main stitch T1 of one seam T. A seam of the condensed seam T2 is formed, and then, from the end position w6 of the condensed seam T1 of the one seam T to the interruption position of the other seam R (the seam of the condensed seam R3 of the other seam R) Start position) The cloth is fed to the upstream side in the cloth feeding direction up to w1, and then the formation of the seam of the main seam R2 (continuous to the main seam R1) is resumed from the interruption position w1 of the other seam R. And form a straight cut Next, the seam of the condensed seam R3 that is continuous with the main seam R2 of the other seam R is formed, and from the end position w6 of the above-mentioned seam T to the interrupted position w1 of the seam T. A control program for controlling the driving of the spindle motor 101, the one-needle stop mechanism 120, the large presser mechanism 1 and the knife motor 303 is stored in the ROM 152 so as to decelerate the raising / lowering speed of the center knife 301 when the cloth is fed idle.
Then, when the CPU 151 executes the control program, the stitches are formed by the following method.
The formation of the seam is started after the operator presses the operation start switch or the like, and the formation of the linear cut is started by the center knife 301 being moved up and down at a lifting speed corresponding to the cloth feeding speed. The control of the CPU 151 of the control device 5 up to this time is the same as that at the time of forming the seam of the back tack stitch portion described above.
In addition, the seam of the condensed seam here means a seam formed with a small stitch pitch, and the seam of the main seam part forms a seam by feeding the cloth at a normal feed pitch. A so-called normal seam is shown, and here, this normal seam is referred to as a seam of a main seam to distinguish it from the seam of the above-mentioned condensed seam.

As shown in FIGS. 15 and 16, when the CPU 151 executes the control program, first, the CPU 151 drives the solenoid valve 90 of the air cylinder to move the switching member 81 and moves the two sewing needles 20a and 20a up and down. It moves to a position where it can move (step S41).
At this time, the CPU 151 drives the solenoid valve 90 of the air cylinder to move the switching member 81 so that the contact protrusion 81a is positioned above the driven link 62 provided on both needle bars 20. .

Next, the CPU 151 determines whether or not the formation of one of the seams (R1, T1) of both the seams (R, T) is completed, that is, two seams (R, T). ) Is determined whether the rear end portion is located further downstream in the cloth feeding direction (step S42). This determination may be made at the end of formation of the seam of the main stitch portion (R1, T1) as in the present embodiment, but each portion of the preset seam (R, T) is preset. It may be determined from the sewing length data. Here, when the CPU 151 determines that the formation of any stitches of the main stitch portion (R1, T1) is not completed (step S42: NO), the CPU 151 drives the spindle motor 101 and the large presser mechanism 1. As a result, the stitches of the main stitch portions (R1, T1) of both the stitches (R, T) that are currently being formed are formed, and the center knife 301 is moved up and down by driving the knife motor 303, thereby forming a straight cut Is formed (step S43).
Here, when forming the stitches of the main stitching portions R1 and T1 of both the stitches R and T, the stitches are formed by dropping the needles in the order of the needle drop positions w0 and w1.

Then, the CPU 151 continues the formation of the stitches at the main stitching portion (R1, T1) until it is determined that the formation of any one of the stitches at the main stitching portion (R1, T1) has been completed.
In step S42, when the CPU 151 determines that the formation of the seam of the main stitch portion (R1, T1) has been completed (step S42: YES), the CPU 151 drives the solenoid valve 90 of the air cylinder to In order to drive only one needle bar 20 (right side) involved in the formation of one seam (T) whose rear end portion is located further downstream in the cloth feeding direction, it is determined that the formation of the seam has been completed. The switching member 81 is moved so that the contact protrusion 81a is positioned above the driven link 62 provided on the other needle bar 20 (left side) stopped by the contact protrusion 81a of the switching member 81, and one sewing needle 20a is moved. , The formation of the seam by the other sewing needle 20a is interrupted so that the sewing can be performed only by one sewing needle 20a (step S44).

Next, the CPU 151 determines whether or not the formation of the seam of the condensed seam (T2) of one (right) seam (T) has been completed (step S45). Here, when the CPU 151 determines that the formation of the stitches of the condensed stitch portion (T2) of one stitch (T) has not been completed (step S45: NO), the CPU 151 causes the spindle motor 101 and the presser motor 102 to move. By driving, the one sewing needle 20a is moved up and down while the fabric is conveyed to the downstream side in the cloth feeding direction through the large presser mechanism 1 to move the one sewing needle 20a up and down, and the condensed stitch portion (T2) of one seam (T). ) Is formed (step S46).
Here, when forming the stitches of the condensed stitch portion T2 of one stitch T shown in FIG. 15, the stitches are formed by dropping the needles in the order of the needle drop positions w1, w2, w3, w4, w5, and w6.
Then, the CPU 151 continues the formation of the stitches in the condensed stitch portion (T2) until it is determined that the formation of the stitches in the condensed stitch portion (T2) has been completed.

In step S45, when the CPU 151 determines that the formation of the stitches of the condensed stitch portion (T2) has been completed (step S45: YES), the CPU 151 changes the sewing needle to be used from one sewing needle 20a (right needle) to the other. To the sewing needle 20a (left needle).
Here, when the sewing needles 20a, 20a used for sewing are switched from one needle (right needle) to one needle (left needle), they cannot be switched at a time, so switching is performed according to the following procedure.
The CPU 151 drives the electromagnetic valve 90 of the air cylinder as soon as one of the sewing needles 20a (right needle) starts to rise from the final needle drop point (w6) of the condensed stitching portion, and the contact projection 81a of the switching member 81 Is moved above the release pin 66, and by advancement of the clutch member 61 due to reaching the top dead center of the needle bar 20, the two sewing needles 20a, 20a can be moved up and down to enable sewing with both needles ( Step S47).

Then, when the pair of balances (not shown) of the sewing machine body 12 reaches the top dead center, the CPU 151 stops the driving of the respective parts such as the spindle motor 101 and temporarily suspends the sewing (step S48).
At this time, the CPU 151 decelerates the female motor 303 so that the number of rotations is set in advance by the setting switch 85 and the numeric keypad 86 (step S49). Thereby, the raising / lowering speed of the center knife 301 is decelerated until it becomes a predetermined speed lower than the speed at the time of the above-mentioned linear cut formation. This is because the center knife 301 is not stopped even during idle feeding in order to stabilize the drive. Therefore, when the cloth is not cut, the number of times the center knife 301 and the fixed knife slide is reduced as much as possible. This is to reduce noise generated during sliding and prevent wear of each knife.
Next, after reducing the rotational speed of the female motor 303, the CPU 151 finishes the formation of the stitches of the condensed stitch portion (T2) of one stitch (T), and the needle drop position is changed to the other (without moving the needle up and down). The large presser mechanism 1 is driven so as to reach the interruption position (w1) in the formation of the seam (R) on the left side, and the cloth is fed upstream in the feeding direction (cloth feeding in the direction B in FIG. 15) (step) S50: Skip feed step).

Next, the CPU 151 switches the sewing needles 20a, 20a used for sewing from both needles to the other single needle (left needle) (step S51).
When switching from both needles to one needle (left needle), the CPU 151 stops one of the two sewing needles 20a, 20a (right needle) upward, so that the solenoid valve of the air cylinder After moving the switching member 81 so that the contact protrusion 81a is positioned above the driven link 62 provided on the needle bar 20 of one sewing needle 20a (right needle) to be driven and stopped 90, The spindle motor 101 is stopped in a state where the spindle motor 101 is rotated in the reverse direction so that the contact protrusion 81a is brought into contact with the driven link 62 and the driven link 62 is pushed down. Thereby, the clutch member 61 corresponding to the needle bar 20 of one sewing needle 20a (right needle) is retracted, and the sewing needles 20a, 20a used for sewing are switched from both needles to one needle (left needle).
Next, the CPU 151 accelerates the reduced rotational speed of the female motor 303 to the rotational speed before the deceleration (step S52). Thereby, the preparation for the formation of the seam and the cut is completed again.
Note that the transition of the rotational speed of the female motor 303 is the same as in the case of the back tack stitched portion shown in FIG.

Next, the CPU 151 determines whether or not the formation of the seam of the main seam (R2) of the other seam (R) has been completed (step S53). Here, when the CPU 151 determines that the formation of the seam of the main seam (R2) of the other seam (R) has not been completed (step S53: NO), the CPU 151 causes the spindle motor 101 and the presser motor 102 to move. By driving, the other sewing needle 20a is moved up and down while conveying the cloth downstream in the cloth feed direction via the large presser mechanism 1, and the interruption position (w1) for forming the other (left side) seam (R). Then, the formation of the seam of the main stitching portion (R2) is resumed and the formation of the linear cut by the center knife 301 is resumed (step S54).
Here, when forming the seam of the main stitch portion T2 of the other seam T shown in FIG. 15, it is formed by causing needle drop in the order of the needle drop positions w1, w7, and w8. Then, the CPU 151 continues the formation of the seam of the main stitch portion (R2) until it is determined that the formation of the seam of the main stitch portion (R2) has been completed.

In step S53, when the CPU 151 determines that the formation of the seam of the main stitch portion (R2) has been completed (step S53: YES), the CPU 151 determines that the condensed stitch portion (R3) of the other (left) stitch (R). It is determined whether or not the formation of the seam has been completed (step S55). Here, when the CPU 151 determines that the formation of the stitches of the condensed stitching portion (R3) has not been completed (step S55: NO), the CPU 151 drives the spindle motor 101 and the pressing motor 102 to perform large pressing. The other sewing needle 20a is moved up and down while transporting the fabric to the downstream side in the cloth feeding direction via the mechanism 1 to form the stitches of the condensed stitch portion (R3) of the other stitch (R) ( Step S56).
Here, when forming the stitches of the condensed stitch portion R3 of the other stitch R shown in FIG. 15, the stitches are formed by dropping the needle drop positions w8, w9, w10, w11, w12, and w13 in this order.

Then, the CPU 151 continues the formation of the seam of the condensed seam (R3) until it is determined that the formation of the seam of the condensed seam (R3) has been completed.
In step S55, when the CPU 151 determines that the formation of the seam of the condensed seam (R3) of the other seam (R) has been completed (step S55: YES), the CPU 151 stops the cloth feed by the large presser mechanism 1. This is the end of this process.

<Effect>
According to the edge stitch sewing machine 100, the control device 5 controls the driving of the spindle motor 101, the solenoid valve 90 of the air cylinder and the large presser mechanism 1 by the CPU 151,
When forming the rear ends of the two seams R, T, the start position w1 of the condensed seam of one seam T where the rear end of the two seams R, T is located further downstream in the cloth feed direction. Until the two seam portions R1 and T1 are formed and linear cuts are formed, and then the formation of the other seam R is interrupted and the continuous seam T1 of the one seam T is continuous. A seam is formed at the seam T2, and then the cloth is fed inward from the end position of the condensed seam T2 of the one seam T to the interruption position w1 of the other seam R toward the upstream side in the cloth feed direction. Next, the formation of the seam of the main seam R2 is resumed from the interruption position w1 of the other seam R and a straight cut is formed, and then the seam of the main seam R2 of the other seam R is continued. Form the seam of condensed seam R3 And decelerating the elevator speed of the center knife 301 during the idle feeding of the fabric.
Thereby, since the control apparatus 5 controls the drive of the knife motor 303 so that the raising / lowering speed of the center knife 301 is decelerated when the cloth is fed idle, the number of sliding of the center knife 301 can be reduced, Sliding noise can be reduced. Moreover, since the frequency | count of sliding of the center knife 301 reduces, the wear amount of the center knife 301 reduces and the lifetime of the center knife 301 can be extended.

<Others>
The present invention is not limited to the above embodiment.
In the present invention, (1) there is a deviation in the sewing end position of two seams, (2) there is a cloth feed in the sewing process, and (3) the cloth is fed by the center knife before and after the cloth feed. Any sewing procedure can be applied as long as the condition that there is a cutting step is satisfied, and the forming sequence of the main stitching portion, the back tack stitching portion, and the condensation stitching portion can be arbitrarily changed.
For example, in the above-described embodiment, the sewing pitch is determined only by feeding by the large presser mechanism 1 without performing needle swinging at the time of forming each stitch of the main stitch portion, the back tack stitch portion, and the condensed stitch portion. When the stitch is formed, the CPU 151 controls the needle swing motor 105 in addition to the large presser mechanism 1, so that the sewing pitch can be appropriately changed by using both the fabric feed and the needle swing by the large presser mechanism 1.
In the one-needle stop mechanism in the above embodiment, both needles are switched with one air cylinder. Therefore, when switching from one needle (left needle) to one needle (right needle), both needles are temporarily switched. Although it was necessary to switch to one needle after switching, for example, as shown in the patent document (Japanese Patent Publication No. 4-52160), each needle can be stopped by an independent air cylinder. In this way, it is not necessary to switch to both needles and the number of parts increases, but the workability can be improved.

The perspective view which shows the schematic structure of the whole bead stitch sewing machine. The front view of the needle bar mechanism which showed the state which exists in a top dead center position in the two-needle holding state. (A) is a side view of the needle bar, (B) is a front view of the needle bar. The front view of the needle bar mechanism which showed the state which exists in a bottom dead center position in the two needle holding state. Sectional drawing of the needle bar mechanism by the cross section along the XZ plane while passing the centerline of one needle bar in the operation state of FIG. The front view of the needle bar mechanism which showed the state immediately after canceling the holding state of one needle bar. Sectional drawing of the needle bar mechanism by the cross section along the XZ plane while passing the centerline of one needle bar in the operation state of FIG. The front view of the needle bar mechanism which showed the state which canceled the holding state of one needle bar and moved to the bottom dead center. The perspective view of a binder. The perspective view which shows the structure of a center knife mechanism. The block diagram which shows the structure in connection with the control apparatus in a bead stitch sewing machine. The figure which shows the formation method of the seam of a back tack sewing part. The flowchart which shows the formation method of the seam of a back tack stitching part. The figure which shows the change of the rotation speed of the knife motor before and behind the idle feed of cloth. The figure which shows the formation method of the seam of a condensed stitch part. The flowchart which shows the formation method of the seam of a condensed stitch part. The figure which shows the formation method of the seam of a back tack seam part in case the position of the rear-end part of two seams has shifted | deviated. The figure which shows the formation method of the stitch of the condensation stitch part in case the position of the rear end part of two stitches has shifted | deviated.

Explanation of symbols

1 Large presser mechanism 2 Binder 5 Control device (control means)
10 Needle bar mechanism (needle up / down movement mechanism, needle swing mechanism)
12 Sewing machine body 20 Needle bar 20a Sewing needle 50 Needle bar vertical movement mechanism (needle vertical movement mechanism)
100 Sewing machine sewing machine 101 Main shaft motor 120 Single needle stop mechanism 300 Center knife mechanism 301 Center knife 303 Female motor P The other seam Q One seam R The other seam T One seam P1 Main seam P2 Main seam P3 Back tack seam Part Q1 Main sewing part Q2 Back tack sewing part R1 Main sewing part R2 Main sewing part R3 Condensation sewing part T1 Main sewing part T2 Condensation sewing part

Claims (3)

A single-needle stop mechanism that holds two sewing needles and has two needle bars that are driven by a spindle motor to move up and down and that can be stopped individually at the raised position. A sewing machine main body that sews the body cloth and the ball cloth by forming the two seams by the vertical movement of the two needle bars driven by the spindle motor,
A binder that holds the tamafu on the fabric,
A large presser mechanism that has a pair of pressing arms that press down and hold the fabric and the drape while holding down the binder, and that conveys the fabric and the drape along the cloth feeding direction;
A center knife disposed downstream of the needle drop position of the two sewing needles in the cloth feeding direction; and a knife motor that raises and lowers the center knife; and the center knife is moved at a predetermined lifting speed by driving the knife motor. A center knife mechanism that is moved up and down to form a linear cut between the two seams,
The spindle motor is formed so that a back-tack seam having a different rear end position is formed at the rear end of the two seams, and the linear cut is formed between the two seams. In the edge stitch sewing machine comprising the one-needle stop mechanism, the large presser mechanism and the control means for controlling the female motor,
When the control means forms the rear ends of the two seams, the control means includes two rear ends of one of the two seams up to the rear end of one of the stitches located further downstream in the cloth feeding direction. Forming a seam of the main seam and forming the straight cut, and then interrupting the formation of the other seam and continuing the seam of the back tack seam of the seam of the main seam of the one seam Then, the cloth is fed in the cloth feeding direction downstream from the end position of the back-tack stitching portion of the one seam to the interruption position of the other seam, and then the other seam Resuming the formation of the seam of the main seam from the interrupted position and forming the linear cut, and then forming the seam of the back tack seam continuous to the main seam of the other seam; and The center of the cloth The spindle motor elevating rate of female to decelerate than the predetermined lift speed, the piece needle stop mechanism, welting sewing machine and controls the driving of the large pressing mechanism and the knife motor. A single-needle stop mechanism that holds two sewing needles and has two needle bars that are driven by a spindle motor to move up and down and that can be stopped individually at the raised position. A sewing machine main body that sews the body cloth and the ball cloth by forming the two seams by the vertical movement of the two needle bars driven by the spindle motor,
A binder that holds the tamafu on the fabric,
A large presser mechanism that has a pair of pressing arms that press down and hold the fabric and the drape while holding down the binder, and that conveys the fabric and the drape along the cloth feeding direction;
A center knife disposed downstream of the needle drop position of the two sewing needles in the cloth feeding direction; and a knife motor that raises and lowers the center knife; and the center knife is moved at a predetermined lifting speed by driving the knife motor. A center knife mechanism that is moved up and down to form a linear cut between the two seams,
The spindle motor, so as to form stitches of condensed stitches at different positions of the trailing ends at the rear ends of the two stitches, and to form the linear cut between the two stitches, In a bead stitch sewing machine comprising the one-needle stop mechanism, the large presser mechanism, and a control means for controlling the female motor,
When the control means forms the rear end of the two seams, the control means reaches the start position of the condensed stitch portion of one of the two stitches where the rear end portion is located further downstream in the cloth feeding direction. Forms the seam of two main stitches and forms a straight cut, then interrupts the formation of the other seam and forms the seam of the condensed seam that continues to the main seam of the one seam Next, the cloth is fed to the upstream side in the cloth feeding direction from the end position of the condensed seam of the one seam to the interruption position of the other seam, and then the interruption position of the other seam. The formation of the seam of the main stitching portion is restarted and the straight cut is formed, and then the stitch of the condensed stitching portion continuous to the main stitching portion of the other stitch is formed, and When sending the center The spindle motor so as to decelerate than the predetermined lift speed lifting speed of the scan, the piece needle stop mechanism, welting sewing machine and controls the driving of the large pressing mechanism and the knife motor.   3. The edge stitch sewing machine according to claim 1 or 2, further comprising setting means for setting a rotational speed of the knife motor when the cloth is fed in an idle state.

Images