KR20020079459A - A sewing machine for overlocking - Google Patents

Abstract

PURPOSE: To prevent the detachment of a bobbin thread at the time of cutting the bobbin thread in a hole sewing machine. CONSTITUTION: The hole sewing machine 10 is provided with a bobbin thread draw-in device 80 provided with a bobbin thread draw-in means 80a slackening the bobbin thread 38 by drawing in the bobbin thread 38 by a prescribed operation and then returning to an initial state, a feed bar 13 moved between an origin position and a sewing position and a bobbin thread cutting device 37 comprising a fixed knife 44, a movable knife 50, a clamping member clamping the bobbin thread at the time of cutting the bobbin thread and a thread hold opener 64 turning the clamping member to the state capable of inserting or releasing the bobbin thread before and after cutting the bobbin thread. At the time of cutting the bobbin thread 38, after the bobbin thread draw-in means 80a is made to perform the prescribed operation from the initial state, the bobbin thread 38 is cut by the bobbin thread cutting device 37 in the state of clamping the bobbin thread 38 by the clamping member and then, the bobbin thread draw-in means 80a is returned to the initial state before releasing the bobbin thread 38 by the thread hold opener 64.

Description

Knit Sewing Machine {A SEWING MACHINE FOR OVERLOCKING}

The present invention relates to a sewing machine for forming a hole, such as a buttonhole, and simultaneously overlocking the hole.

In a conventional sewing machine, a seam is formed around a hole by cooperation of a sewing needle which is shaken from side to side and left and right by the upper thread, and a looper which is disposed under the sewing needle and passes through the lower thread.

In this type of knitting machine, a lower thread cutting device as described in Japanese Patent Laid-Open No. 2000-300885 is arranged. 2 shows the lower thread cutting device 37 described in the above publication. The lower thread cutting device 37 is configured to horizontally drive the moving blade 50 to face the fixed blade 44 and to cut the lower thread 38 and the screen 34 between the two.

Fixing means 55 is arranged in the lower thread cutting device 37, and the lower thread 38 and the screen 34 are clamped by the fixing means 55 before cutting, thereby making it easier to cut by applying tension to each thread. The next sewing is started smoothly by continuing to sandwich the thread after cutting. The fixing means 55 is arranged between the fixing plate 56 and the grabbing plate 58 by arranging the grabbing plate 58 and the lower thread grabbing plate 60 above and below the fixing plate (lower thread clamp fixing plate) 56 ( 34, the lower thread 38 is clamped between the fixing plate 56 and the lower thread holding plate 60.

In addition, a bottle opener 64 is disposed near the moving blade 50. When the thread catching opener 64 is rotated together with the mobile scalpel 50 just before cutting the thread, the operating portion 65 of the tip presses the thread catching pin 62 of the fixing means 55 downward, thereby The lower thread catching plate 60 is pushed downward to open the gap between the fixed plate 56 and the lower thread catching plate 60, and the lower thread 38 is securely sandwiched therebetween.

In addition, although it is not described in the said publication, a thread is consumed to some extent at the time of cutting | disconnection. There, a lower thread pulling device for pulling and loosening the lower thread is disposed below the looper, so as to draw in advance the degree of consumption of the thread before the thread cutting. In this way, the tension is not applied to the bobbin thread after the thread is cut while the thread is in a tight state at the time of cutting.

When cutting the thread, the thread is first pulled by the lower thread pulling device before the thread is cut, and then the movable blade 50 is placed on the screen 34 by the recess 50a and the lower thread by the recess 50b. 38) is rotated toward the fixed knife 44 in the state which captured each. At this time, the thread catching opener 64 is also rotated together, and the fixing means 55 is opened by the operating part 65 of the opener 64 catching the thread just before cutting. The examination 34 and the lower thread 38 are respectively clamped. Subsequently, the screening 34 and the lower thread 38 are cut by the mobile blade 50 coming into contact with the fixed blade 44. After that, the moving blade 50 and the thread opener 64 rotate in the reverse direction and return to their original positions.

By the reverse rotation of the thread catching opener 64, the operation part 65 opens between the fixed plate 56 and the lower thread catching plate 60 through the pin catching thread 62 again. At this time, the lower thread 38 is in a state where the tension is not normally applied to the lower thread 38, so that the lower thread 38 is rarely removed as described in paragraph 25 of the above publication.

However, when the lower thread is a kind of thread of poor slip such as a spanner, or when the remaining amount of the lower thread supply source becomes smaller, the load on the lower thread supply source becomes high and the lower thread along the path from the lower thread supply source to the lower thread pulling device This stretch is reduced and the actual amount of pull before cutting is reduced. Since the tension is generated in the lower thread cut and clamped in this state, the lower thread 38 may loosen and come off when the cutting plate 56 is opened between the fixing plate 56 and the lower thread holding plate 60 after cutting.

If the bobbin thread is missing, it is a problem that a good seam cannot be formed due to splashing of the sewing start or a bad thread finish during the next sewing.

Therefore, if the amount of thread pull by the lower thread pulling device before thread cutting is made too large, loosening of the lower thread as described above can be prevented. However, if the thread pulling amount is increased too much, the lower thread becomes loose and the screening and the lower thread before cutting are difficult to be divided, and the amount of loosening due to the movement of the moving blade at the time of cutting cannot be absorbed, and the lower thread is matched with the fixed blade. Since this is not taut, there is a possibility of poor cutting.

An object of the present invention is to form a good knitting seam by being able to reliably cut a lower thread in a sewing machine and to prevent loosening of the lower thread during cutting.

1 is an example of a sewing machine of the present invention, (a) is a perspective view of the whole, (b) is a partial side view showing the broken bed portion.

Figure 2 is a perspective view showing the lower thread cutting device of the sewing machine of Figure 1;

3 is a plan view showing the shape of the lower thread cutting device of the lower thread cutting device of FIG.

4 is a plan view showing the fixing means of the lower thread cutting device of FIG.

5 is a plan view of the looper portion and the looper support portion viewed from the front;

6 is a side view showing the upper thread cutting device.

7 is a block diagram showing a control circuit of the sewing machine of FIG.

FIG. 8 shows data contents that can be set for crop sewing. FIG.

9 is a view schematically showing a buttonhole and a sewing needle to explain the seam formed in the sewing machine of FIG.

10 is a view showing an operation panel.

Fig. 11 is a flowchart showing a series of operations of button knitting sewing.

12A is a diagram showing an operation panel for setting a memory switch number, and (b) is a table showing memory switch setting contents.

Fig. 13 is a flowchart showing setting processing in the memory switch setting mode.

※ Explanation of symbols about main part of drawing ※

10: sewing machine 11: needle bar

12: bed portion 13: transfer table

14: arm 18: sewing needle

20,70: looper part, looper support part (looper device)

37: lower thread cutting device 38: lower thread

44: fixed blade 50: mobile blade

55: fixing means

56, 58, 60: fixed plate, screen holding plate, bottom thread holding plate

64: thread opener 65: operating part

80: lower thread drawer

80a: lower thread pulling means

92: air cylinder (upper thread cutting air cylinder)

F: Sewing 110: Control Circuit

150: operation panel (selection means) 200: operation panel (selection means)

In order to solve the above problems, the invention described in claim 1 is, for example, as shown in Figs.

A looper device (looper portion 20 and looper support portion 70) disposed on the bed portion 12 so as to face the needle rod 11 disposed on the arm portion 14 of the sewing machine frame and operating in synchronization with the needle rod. Wow,

A lower thread pull composed of a lower thread pull means (80a) for loosening the lower thread by returning to the original state after pulling the lower thread (38), and a lower thread pull drive means (upper thread cutting air cylinder (92)) for driving the lower thread pull means. Device 80,

A transfer table 13 disposed on an upper surface of the bed portion, in which a sewing material F is placed to move at least between the origin position and the sewing position,

A mobile scalpel 50 disposed on the transfer table for cutting the lower thread, and a clamping member (a thread clamp fixing plate 56, a grabbing plate 58, and a lower thread holding plate 60) for clamping the lower thread from before cutting to after cutting. ) And a lower thread cutting device 37 comprising a release member (a threading opener 64) which makes the pinch member insertable or unleashed before and after the lower thread cutting.

In a sewing machine 10 for sewing a sewing thread by cooperation of a needle bar and a looper device, and then cutting the lower thread by a lower thread cutting device,

When the lower thread is cut, the lower thread is cut by the lower thread cutting device in a state where the lower thread is clamped by the clamping member, and then the lower thread is cut by the release member. The lower thread pulling means is returned to its original state through the lower thread pulling drive means before being released.

According to the invention of claim 1, the lower thread pulling means first performs the predetermined operation from the initial state and pulls the lower thread, and in this state, the lower thread is clamped by the clamping member, and then the lower thread is cut by the lower thread cutting device. After the lower thread pulling means is returned to its original state to loosen the lower thread, the clamping member is brought into a state in which the lower thread can be released. At this point, the lower thread is loosened and does not escape the clamping member.

In other words, the lower thread is loosened before the fixing means is released, so even if the type of the lower thread or the load on the thread supply side is large, the lower thread is not released from the clamping member, and the sewing is smooth and the sewing seams are not splashed in the next fixed sewing. Can be formed.

In addition, the lower thread is pulled by the lower thread pulling device before cutting, so that the lower thread is tensioned to some extent so that it can be easily cut.

Here, when the lower thread pulling drive means is turned on, the lower thread pulling means performs the predetermined operation, and when turned off, the lower thread pulling means may be returned to the initial state and the thread may be loosened. The drive means may be configured to be turned ON and OFF. As the lower thread pulling drive means, a cylinder, a solenoid, a motor, or the like may be held, and a driving source dedicated to the lower thread pulling device may be used, or a driving source for other operations may be used.

The invention described in claim 2 is, for example, as shown in Figs. 10 and 12 in the knitting machine according to claim 1,

The transfer table is to move from the sewing position to the home position after the end of sewing and before cutting the lower thread.

Selecting means (operation panels 150, 200) for selecting whether to pull or loosen the lower thread by the lower thread pulling device before the lower thread cutting is characterized in that the arrangement.

If the amount of movement from the sewing position of the transfer stage to the home position before cutting the lower thread is long, the lower thread following the sewing material on the transfer stage is also consumed. According to the invention described in claim 2, it is possible to select whether the lower thread is pulled or loosened by the lower thread pulling device before the lower thread cutting by the selecting means. Therefore, when the lower thread consumption is large, by selecting the lower thread pull by the selection means it is possible to prevent the excessive tension on the lower thread when moving the conveyer. In addition, when the movement amount is short and the consumption of the bobbin thread is small, if it is selected so as not to be pulled by the selection means, unnecessary bobbin pulling is not performed and the bobbin thread can be prevented from loosening more than necessary.

The invention described in claim 3 is the knitting machine according to claim 1,

The transfer table is to move from the sewing position to the home position after the end of sewing and before cutting the lower thread.

It is characterized by automatically determining whether the lower thread is pulled or loosened by the lower thread pulling device immediately before cutting the lower thread according to the moving length from the sewing position to the origin position.

According to the invention described in claim 3, the same effects as in claim 2 can be obtained, and the automatic determination is more convenient.

According to the invention described in claim 4, in the knitting machine according to claim 1, for example, as shown in Figs.

Selection means for selecting whether to pull or loosen the lower thread by the lower thread pulling device for the movement of the transporting point at the next sewing start after cutting the lower thread after starting cutting the lower thread. It is characterized in that the operation panel 150, 200) is arranged.

According to the invention described in claim 4, when the amount of movement of the conveyance table from the home position at the start of sewing to the sewing position is long, the lower thread held by the fixing means of the lower thread cutting device to be transported is also consumed a lot. According to the invention described in claim 4, by means of the selection means, it is possible to select whether the lower thread is pulled or loosened by the lower thread pulling device for the next sewing. Therefore, when the amount of lower thread consumption due to the movement at the start of the next sewing is large, selecting the lower thread pull by the selecting means can prevent the tension from being applied to the lower thread during the transfer of the next sewing feed table. The fact that the excessive force is not applied to the lower thread may be a weak clamp force by the holding member, and miniaturization of each member constituting the holding member is possible.

When the amount of movement is short and the consumption of the lower thread is small, if it is selected not to be pulled by the selecting means, unnecessary lower thread pulling is not performed and the lower thread can be prevented from loosening more than necessary.

The invention described in claim 5 is the knitting machine according to claim 1,

At the start of sewing, the transfer table is moved from the origin position to the sewing position, and at the next sewing start after cutting the lower thread, the origin of the next sewing is pulled or loosened by the lower thread pulling device for the movement of the carriage. It is characterized by automatically determining according to the length of movement from the position to the sewing position.

According to the invention described in claim 5, the same effects as in claim 4 can be obtained, and the convenience is further improved from automatic determination.

In claim 3 or 5, "depending on the moving length" may be determined based on the actual moving length, or may be determined based on the sewing length related to the moving length and the like.

EMBODIMENT OF THE INVENTION Embodiment of this invention is described in detail based on following drawing.

The sewing machine 10, which is an example of the present invention shown in Figs. 1 (a) and (b), forms a buttonhole H formed of the eyelet part h1 and the parallel part h2 shown in Fig. 9; At the same time, the overlock W is provided around the button hole H. The overlock W consists of a right sewing part w1, an eyelet sewing part w2, a left sewing part w3, and a straight-sewn sewing part w4.

The sewing machine 10 is composed of a bed portion 12, which is a substantially rectangular box body, and an arm portion 14 placed on the bed portion 12, and a bottom cover 16 on a sewing machine table (not shown). Is put on). At the front of the arm 14, the needle bar 11 having the sewing needle 18 at the lower end thereof is disposed so as to be able to move in the shank and to move the needle in the left and right direction (vertical direction in the ground of FIG. 1 (b)). .

In addition, the bed portion 12 is provided with a looper support portion 70 having an upper portion of the looper portion 20 opposite to the needle bar 11. The needle bar 11 and the looper part 20 operate in synchronism to form a sewing stitch by cooperation of both. In addition, the needle bar 11 and the looper support part 70 are made to rotate synchronously when sewing the eyelet part h1 of the button hole H in the shape of a yarn. The looper portion 20 and the looper support portion 70 will be described later.

In addition, the examination (not shown) which draws out the examination 34 (FIG. 2, FIG. 3) drawn out from the thread supply source (not shown) in the vicinity of the looper part 20 between the needle vibration positions on the left and right sides of the sewing needle 18. FIG. The guide mechanism is arranged and configured to reinforce the seam by enclosing the screening 34 in the seam.

In addition, a cloth cutting device comprising a cloth cutting blade (not shown) positioned behind the looper portion 20 and a measuring stand 33 (Fig. 1 (b)) that is folded above the cloth cutting blade is disposed. By operating the cloth cutting device at the required timing, the button hole H is formed in the sewing material F (FIG. 3).

On the upper surface of the bed portion 12, a conveyance table 13 on which the sewing material F is placed is disposed, and the cloth pressing portion 36 for pressing the sewing material F from both sides of the button hole is placed on the conveying table 13. ) Is placed.

The conveyance table 13 forms a thin rectangular box as a whole, and is driven by the X-axis pulse motor 119 and the Y-axis pulse motor 123 (Fig. 7), and the left and right (X) direction and the front and rear (Y) directions. It is possible to move to.

The transfer table 13 has the cloth cutting scalpel and the receiving base 33 above and below a position where the button hole is to be formed in the sewing material F placed on the upper surface in a state of being positioned at a predetermined origin position. Is set to face. During sewing, a button hole is first formed in this position.

Then, the transfer table 13 moves to the sewing start position ahead of the home position by the operation of the start switch 134, and the sewing material F placed on the transfer table 13 is immediately below the sewing needle 18. It is driven to move relative to the required position of. Sewing sewing around the buttonhole H starts from the lower end of the right sewing part w1 in Fig. 9 (a), and is sewn to the left sewing part w3 via the eyelet sewing part w2, and is finally straight-lined. Sewing is performed in the order of sewing (w4). In order to sew in this order, the transfer table 13 starts to move from the sewing start position in the Y direction so that the apex of the button hole H (the tip of the eyelet hole h1) corresponds to the sewing needle 18. It moves to the front until it is in a state of being made, and then it returns to the sewing end position which is almost the same as the sewing start position toward the rear.

The moving distance from the origin position of the conveyance stand 13 to the position (called the end position) of the conveyance stand 13 when the peak of the button hole H is in a state corresponding to the sewing needle 18 is a constant value. For example, 64mm. Therefore, the moving distance to the sewing start (end) position varies depending on the sewing length (m1 value in Fig. 9 (a)) of the buttonhole H, and is shorter by longer and longer by shorter.

When sewing is finished, the transfer table 13 is controlled to return to the home position from the sewing end position. In addition, in this embodiment, when the sewing material F is set, the feed table 13 is moved to a predetermined set position.

Knit sewing machine 10 is arranged the same lower thread cutting device as shown in FIG. Next, the lower thread cutting device 37 disposed on the sewing machine 10 will be described based on FIGS. 2 to 4.

That is, the attachment guide 40 for attaching the fixed blade to the transfer table 13 is fixed, and the fixed blade attachment plate 42 is disposed at the left end of the attachment guide 40. At the rear end of the fixed blade attaching plate 42, the fixed blade 44 is screwed and its free end extends toward the lower thread 38 and the screen 34. The lower arm 38 and the screen 34 are fitted to support the fixing arm 48 freely horizontally swinging through the shaft pin 46 on the feed table 13.

The movable arm 50 is screwed to the fixed arm 48 so as to face the fixed blade 44, and its free end extends toward the lower thread 38 and the screen 34. Two concave portions 50a and 50b are formed at the free end of the movable scalpel 50, and the upper side of the movable scalpel 50 moves upward toward the fixed scalpel 44 by the rocking of the fixed arm 48. The screen 34 is formed in the recess 50a, and the lower thread 38 is captured in the lower recess 50b so as to reliably separate the lower thread 38 and the screen 34 from each other.

The fixed shaft 48 is driven by the lower thread cutting cylinder 30 (FIG. 7) disposed on the underside of the feed table 13, and is shown in the standby position and in FIG. 3 with the shaft pin 46 as the center. It is configured to swing between the cutting position.

Then, the moving blade 50 captures the screen 34 and the lower thread 38 by the recesses 50a and 50b while the fixed arm 48 swings from the standby position to the cutting position. The side surface (backward facing surface) of the moving blade 50 is in contact with the free end to cut the lower thread 38 and the screen 34.

In addition, the attachment guide 40 is provided with a fixing means 55 composed of a fixing plate (lower thread clamp fixing plate) 56 or the like. That is, the fixing guide 56, which is an elongated plate, is disposed on the attachment guide 40 so as to lengthen in the front-rear direction.

On the upper surface of this fixing plate 56, the screen grabbing plate 58 is screwed, and the screen 34 is elastically fixed to the fixing plate 56. As shown in FIG. The lower thread holding plate 56 is screwed to the bottom of the fixing plate 56, and the lower thread 38 is elastically fixed between the fixing plates 56.

The lower thread catching plate 60 is provided with a thread catching pin 62 extending upward through the fixing plate 56 and the screen catching plate 58, and the fixing plate 56 is pushed down by pushing the thread catching pin 62. The rear end of the lower thread holding plate 60 is opened.

The holding member is constituted by the above-mentioned fixing plate 56, the examination grabbing plate 58, and the lower thread grabbing plate 60.

In addition, the fixing arm 48 is provided with a thread catching opener (release member) 64 which engages and disengages the thread catching pin 62 of the lower thread catching plate 60 immediately before cutting to open and close the lower thread catching plate 60. . The threading opener 64 is supported at the same time the base 66 is supported by the fixing arm 48 at the upper portion of the shaft pin 46 by the fixing screws 68 and 68 at the middle hole 67 and 67. The operating portion 65 extends from the 66 in the direction in which the movable blade 50 extends.

The bottom level of the operating part 65 is set to be lower than the upper end of the thread catching pin 62 in the state where the lower thread catching plate 60 is closed, and the pin 62 catching on the bottom of the operating part 65 The lower thread holding plate 60 is to be opened while the upper end is in contact (Fig. 4). By this opening, the lower thread 38 is smoothly inserted between the fixing plate 60 and the lower thread holding plate 60, and conversely, when the lower thread 38 is released while the lower thread 38 is clamped, the lower thread 38 is freed. do.

On the side facing the moving blade 50 of the operating portion 65, a recess 65a facing the pin 62 is formed when the moving blade 50 reaches the position just before reaching the cutting position. do. That is, the thread catching pin 62, which is pushed by the operating section 65 to open the lower thread catching plate 60, is brought to the position corresponding to the recess 65a by the movement of the thread catching opener 64. 64, the bottom thread holding plate 60 is closed by disengaging from the bottom surface. Thereby, the lower thread 38 is firmly fixed before cutting between the fixing plate 56 and the lower thread holding plate 60.

Next, the looper part 20 and the looper support part 70 which comprise the looper apparatus of this invention are demonstrated based on FIG. The looper support part 70 is comprised by arranging each member in the base 71 in which the round ring part 71a, the attachment plate 71b, the support frame 71c, and the shaft part 71d are comprised integrally. do.

In the bed portion 12, a support portion 12a having a circular hole is disposed, and the circular ring portion 71a is fitted in the circular hole so as to rotate freely, and the looper support portion 70 is supported so as to rotate freely. The attachment plate 71b is arrange | positioned at the upper part of the round ring part 71a, and the support frame 71c of the substantially rectangular frame shape which is vertically long up and down is arrange | positioned at the lower part of the round ring part 71a. The shaft part 71d is arrange | positioned under the support frame 71c. A pleat and the like are disposed on the shaft portion 71d, and a timing belt (not shown) is hung on the pliers to rotate the looper supporting portion 70 in the vertical axis direction in synchronization with the needle bar 25. The looper support part 70 and the looper part 20 rotate from 0 degree to 180 degree when the initial rotation position is 0 degree at the time of sewing.

The looper part 20 is arrange | positioned at the attachment plate 71b. The looper portion 20 includes a looper 26 and 26, a spreader 27 and 27 to assist the looper 26 and 26, a tongue portion 22 having a needle hole, and an upper thread cutting blade 28. ) And the like.

The looper spreader drive means which consists of the looper drive shaft 23, the spreader drive shaft 24, etc. is arrange | positioned inside the support frame 71c. That is, the tubular looper drive shaft 23 is disposed along the center of rotation of the looper support portion 70, and the tubular spreader drive shaft 24 is disposed in the looper drive shaft 23. In addition, the spreader drive shaft 24 extends above the looper drive shaft 23.

In the spreader drive shaft 24, a lower thread 38 (indicated by a thick dotted line) from the thread supply source (not shown) toward the needle hole of the tongue portion 22 passes from the lower end of the spreader drive shaft 24 toward the upper end. The lower portion of the looper drive shaft 23 and the spreader drive shaft 24 pass through the shaft portion 71d and protrudes below the looper support portion 70 and is connected to a lower shaft (not shown) via an electric mechanism not shown.

The lower end of the looper driving rod 23b is connected to the looper driving shaft 23 through the looper driving shaft guide 23a. The upper end of the looper drive rod 23b is connected to the looper mount 23c and is connected to the looper mount 23c, and the looper mount 23c is attached. Accordingly, the shanghai motion of the looper driving shaft 23 is converted into a predetermined reciprocating swing motion and transmitted to the looper 26 and 26.

The lower end of the spreader drive rod 24b is connected to the upper end of the spreader drive shaft 24 via the spreader drive shaft guide 24a. The upper end of the spreader drive rod 24b is connected with a spreader actuating cam 24c for operating the spreaders 27 and 27 so that the shank movement of the spreader drive shaft 24 is converted into a predetermined reciprocating swing motion so that the spreader 27 Is passed to (27).

Moreover, in the support frame 71c, in between the lower thread path part 76 and the lower thread path part 76 which extend out of the upper end of the spreader drive shaft 24 and lead the lower thread 38 toward the needle hole side of the tongue-shaped part 22. A lower thread pulling device 80 for pulling the lower thread 38 is disposed.

The lower thread path part 76 includes a frame part 76a attached to the front side of the support frame 71c, each member attached to the frame part 76a, a lower thread catching spring 76b which is a torsion spring, and a tension disk method. The tension tension part 76c, the 1st silage part 76d, the 2nd silage part 76e, etc. are comprised.

The lower thread catching spring 76b is supported by the frame portion 76a so that the coil portion is rotatable so that one end thereof is fixed to the frame portion 76a, the other end of which is extended upward and is extended by the restricting member 76g in the middle. At the same time, the tip is formed in a ring shape at the same time as the movement in the bias direction (right direction in FIG. 5) is regulated.

The lower thread 38 extends from the upper end of the spreader drive shaft 24, and the first thread is caught by the outer portion of the portion 76d and faces downward. Subsequently, the lower thread 38 is caught between the two tension plates constituting the seal tension portion 76c after the second thread is caught by the outer portion of the portion 76e and rotates. Subsequently, the lower thread 38 is caught by the inner part of the part 76e and the first thread is caught by the inner part of the part 76d. Then, the lower thread 38 passes through the ring portion of the lower thread catching spring 76b and passes through a threaded through tube 76f attached to the rounded ring portion 71a, and faces upwards of the looper support portion 70 and passes through the looper 26. It passes through the needle hole of the tongue portion 22, and is directed toward the object to be sealed on the needle plate 19.

In addition, the seal tension portion 76c is tensioned to the lower thread 38 in a closed state, and the lift piece 74b of the lift plate 74 fixed to the lower thread pulling plate 84 to be described later enters between the tension plates ( 38) to open.

The lower thread pulling device 80 includes a lower thread pulling means 80a made of a lower thread pulling plate 84, an operation looper 85, and an air cylinder 92 for cutting the upper thread which is the lower thread pulling driving means (to be described later). It consists of. The lower thread pulling device 80 loosens the lower thread 3 in advance when the lower thread 38 is consumed in addition to sewing, and before the lower thread 38 is consumed in the movement of the transfer table 13 or the lower thread cutting operation. 38). The timing of thread pulling is mentioned later.

The lower thread pulling plate 84 is composed of a base portion 84a, a directing portion 84c extending upward of the base portion 84a, and a lower thread pulling portion 84b to which the lower thread 38 is caught.

The base portion 84a is engaged with the rotating shaft 86 which is supported to rotate freely by a bearing portion (not shown) of the lower end portion of the support frame 71c, and freely rotates together. An arc-shaped long hole 84e is disposed in the base portion 84a, and an operating lever 85 through which the rotating shaft 86 passes through the fixing screw 87 is fastened in the long hole 84e. The operation lever 85 is fixed to the 84a. That is, the lower thread pulling plate 84 and the operating lever 85 are rotated in a plane parallel to the ground of FIG. 5 integrally with the rotation shaft 86 about the rotation shaft 86.

The tip portion 85a of the actuating lever 85 protrudes outward and is positioned outside the rotational track of the looper support portion 70.

The other end of the return spring (lower thread return spring) 81 whose one end is caught by the upper thread cutting operation arm 28a is caught by the operation lever 85. The return spring 81 urges the lower thread pulling plate 84 and the operation lever 85 to rotate back in the counterclockwise direction in the ground of FIG. 5.

In addition, the lower thread pulling portion 84b is provided with a long hole 84d through which the lower thread 38 that is opened through the spring 76b that catches the lower thread passes between the portion 76d of the first threaded portion and the thread through tube 76f. .

The base plate 74 is rotatably attached to the rotation shaft 86 and is fixed to the base portion 84a of the lower thread pulling plate 84 through the long hole 74c, and the base ( It consists of a dish offset piece 74b extending from 74a). The dish piece 74b is disposed so that its tip portion is located directly below the tension portion 76c.

Then, when the lower thread pulling plate 84 rotates clockwise against the return spring 81, the counterpart piece 74b moves upward, and the counterpart piece 74b is the lower thread 38 of the seal tension part 76c. It is inserted between the two plates that sandwich the plate. As a result, the tension applied to the lower thread 38 is released.

When the tip portion 85a of the actuating lever 85 is pushed downward by the drive transmission 99 from the initial state of FIG. 5, the lower thread pulling plate 84 rotates clockwise with the actuating lever 85. . As a result, the lower thread 38 caught in the long hole 84d of the lower thread pulling portion 84b is pulled to the right. At this time, since the tension by the seal tension portion 76c is released as described above, the lower thread 38 is pulled out from the thread supply source side. In this state, when the force pushing the front end portion 85a of the actuating lever 85 downward is released, the lower thread pulling plate 84 and the actuating lever 85 return to the original state by the return spring 81, and the lower thread 38 is returned. This becomes loose.

Next, the upper thread cutting device 90 will be described. The upper thread cutting device 90 is the upper thread cutting blade 28 disposed on the looper portion 20, the upper thread cutting operation arm 28a, and the like, and the upper thread cutting drive formed by arranging each member in the front and rear direction in the bed 12. Means 91.

5, the upper thread cutting operation arm 28a is attached to rotate freely with respect to the attachment plate 71b, and the upper thread cutting blade 28 is attached to the upper portion of the upper thread cutting operation arm 28a. 5, a part of upper thread cutting device 90 is abbreviate | omitted. In FIG. 6, the looper support part 70 etc. are simplified and shown, and the bed part 12 is shown by the dashed-dotted line.

One end of the lower thread pulling return spring 81 is caught by the upper thread cutting operation arm 28a, and is urged to rotate clockwise by the return spring 81, and the upper thread cutting blade 28 is positioned at a predetermined cutting standby position. It is supposed to.

A protrusion 28c is disposed on the upper thread cutting operating arm 28a, and the protrusion 28c is pushed downward by the upper thread cutting driving means 91 so that the upper thread cutting operating arm 28a rotates in a counterclockwise direction. (28) is for performing the upper thread cutting operation.

The upper thread cutting driving means 91 is composed of an air cylinder (upper thread cutting air cylinder) 92 for upper thread cutting, an upper thread cutting link 93, an upper thread cutting drive shaft 94, a crimping part 95, and the like. .

The return spring 92 is supported to freely rotate to the cylinder bracket 96 which is fixed to the bed portion 12 by the fixing screws 96a and 96a at its proximal end. In addition, the return spring 92 advances and retracts the rod portion 92a attached to the front thereof, and the extraction amount of the rod 92a is always constant.

One end of the upper thread cutting link 93 formed in a substantially T-shape is connected to the distal end of the rod 92a so as to be rotatable through the cylinder knuckle 97. The middle part of the upper thread cutting link 93 is supported to rotate freely to the bed part 12 by the rotating shaft 93a. On the other hand, the upper part of the upper thread cutting drive shaft 94 extending in the up-and-down direction is fixed to the sealing portion 94a in the state in which the driving shaft 94 is inserted, and the other end of the upper thread cutting link 93 is the sealing portion ( The upper thread cutting link 93 supports the upper thread cutting drive shaft 94 at the rear in FIG. 6 by being rotatably connected with respect to 94a). A crimping portion 95 is disposed at the upper end of the upper thread cutting drive shaft 94. In addition, when the looper support part 70 is located at a rotational angle of 180 degrees, the crimping part 95 is disposed so that the crimping part 95 and the protrusion 28c of the upper thread cutting blade 28 overlap with each other.

The shaft fixing member 98 is fixed to the lower part of the upper thread cutting drive shaft 94 by the screw 98a, 98a in the state which inserted the upper thread cutting drive shaft 94, and plate-shaped with respect to the shaft fixing member 98. The drive transmission part 99 which is a member is fixed in the state which inserted the upper thread cutting drive shaft 94. As shown in FIG.

According to the upper thread cutting drive means 91, the crimping portion 95 is operated together with the shanghai movement of the upper thread cutting drive shaft 94 by the driving force of the return spring 92.

That is, as shown in FIG. 6, when the return spring 92 is in the off state, the rod 92a is pushed out, and at this time, the crimp portion 95 is stopped at the top dead center. On the other hand, when the return spring 92 is turned on, the rod 92a is retracted, and the crimping portion 95 moves downward by the counterclockwise rotation of the upper thread cutting link 93 to stop at the bottom dead center. . At this time, if the looper support part 70 is in the rotational position of 180 degrees, the upper thread cutting knife 28 located at the cutting standby position is operated by pushing the protrusion 28c downward by the pressing part 95 to cut the upper thread. . When the return spring 92 is turned off again, the crimping unit 95 moves to the top dead center and the upper thread cutting blade 28 moves to the cutting standby position by the force of the return spring of the upper thread cutting blade 28. It is supposed to return.

The drive transmission 99 is disposed above the tip portion 85a of the operating lever 85 as a plate-shaped member almost perpendicular to the axis of rotation of the looper support portion 70. The bottom surface of the drive transmission portion 99 and the tip portion 85a of the operation lever 85 face each other at a predetermined interval in the vertical direction.

The drive transmission portion 99 has a shape of an approximately crescent shape (approximately C-shaped) centered on the axis of rotation of the looper support portion 70 as viewed in the vertical direction, and the looper support portion is formed by an inner arc-shaped edge portion thereof. It is arranged to surround 70. And the center of the circular arc which the inner edge part makes, and the center of rotation of the looper support part 70 are made to correspond substantially. Further, the rotational trajectory of the tip portion 85a of the actuating lever 85 according to the rotation of the looper support portion 70 is located outside the inner edge portion of the drive transmission portion 99 and follows an arc inside the outer edge portion. It is.

The looper supporting portion 70 is in a rotational position of about 0 degrees when sewing starts, and becomes about 180 degrees when finishing sewing. In the meantime, the tip portion 85a of the actuating lever 85 and the drive transmission portion 99 overlap each other in the vertical direction.

When the upper thread cutting drive shaft 94 moves up and down, the drive transmission unit 99 also moves up and down together, folds with respect to the front end portion 85a of the operation lever 85, and the drive transmission unit 99 returns to the spring. When it moves downward at the time of 92, the tip part 85a will be pushed. That is, regardless of the rotational angle of the looper support part 70, when the drive transmission part 99 moves downward, the tip portion 85a of the operation lever 85 is pushed. When the tip portion 85a is pushed downward, the lower thread pulling is performed as described above. In other words, the air cylinder 92 also serves as the lower thread pulling drive in the present invention.

7 shows the control circuit 110 of the sewing machine 10. The control circuit 110 includes the CPU 111, the ROM 112, the RAM 113, and the interface 114, 15. , Various driving circuits, an operation panel 150, a start switch 134, and the like.

The ROM (Read Only Memory) 112 writes a control program and control data for sewing sewing.

The RAM (Random Access Memory) 113 stores a plurality of pattern data (print control data) and at the same time stores one pattern data selected through the operation panel 150, and changes the value of the data item in the pattern data. In that case, the value is also remembered. The RAM 113 also functions as a memory area that is temporarily used in various processes during sewing. It also stores the seam data (described later) generated from the pattern data.

The CPU (Central Processing Unit) 111 controls a series of processes related to sewing sewing in accordance with the control program and control data of the ROM 112.

The CPU 111 is connected to the operation panel 150 through the interface 114, controls the display on the operation panel 150, and receives input signals input through the operation panel 150 to select and select various settings. Changes are to be made. The operator can select the pattern data shown in FIG. 8 through the operation panel 150 or change the number of each data item of the selected pattern data. The operation panel 150 will be described later.

In addition, the CPU 111 is connected to the main shaft servomotor driving circuit 116 via the interface 115, and controls the rotation of the main shaft servomotor 117. The main shaft servomotor 117 drives the upper shaft (not shown) which drives the sewing needle 18 up and down, and the lower shaft (not shown) which operates a looper spreader drive means.

In addition, the CPU 111 is connected to the X-axis pulse motor driving circuit 120 through the interface 118 and is connected to the Y-axis pulse motor driving circuit 122 through the interface 121 to the X-axis pulse motor 119. And drive the feed table 13 in a predetermined direction while controlling the drive of the Y-axis pulse motor 123.

The CPU 111 is connected to the Z-axis pulse motor driving circuit 125 via the interface 124 and controls and drives the Z-axis pulse motor 126.

In the sewing machine 10, the rotation of the spindle servomotor 117 is transmitted to the needle bar 18 and the looper / spreader driving means, so that the looper is synchronized with the shank movement and the needle vibration motion of the needle bar 11. 26) 26 and spreaders 27 and 27 are operated, thereby forming a seam on the sewing material F placed on the feed table 13.

The needle bar 11 and the looper supporting portion 70 are connected to a rotating mechanism including a Z-axis pulse motor 126, a timing belt 31, a transmission shaft 32 (FIG. 1B), and the like. When spinning around the eyelet sewing portion w2 in a radial shape, it is driven by this rotating mechanism, and the sewing needle 18 and the looper portion 20 are rotated in synchronization.

The CPU 111 is connected to the lower thread cutting cylinder drive circuit 128 through the interface 127 to control and drive the lower thread cutting cylinder 30. In addition, the upper thread cutting cylinder drive circuit 130 is connected to the upper thread cutting cylinder driving circuit 130 through the interface 129 to perform the upper thread cutting or the lower thread pulling as described above.

The CPU 111 is connected to the cloth cutting motor driving circuit 132 through the interface 131 and controls and drives the cloth cutting motor 133.

In addition, the CPU 111 is connected to the start switch 134 via the interface 114, and when the start signal is input from the start switch 134, the main shaft servomotor 117 or the like is driven at a predetermined timing, and the sewing is performed. The cloth cutting process and the upper thread and the lower thread cutting process are performed.

Data stored in the RAM 113 will be described based on FIGS. 8 and 9. FIG. 8A shows a table t1 showing the pattern data when the button is sewn on. Here, nine kinds of pattern data can be stored, and one pattern data has 1 to 9 data items.

Data item 1 is to set the shape of the eyelet portion h1. As shown in Fig. 9B, the size of the eyelet portion h1 is defined by the width width ew and the length length el, and the combination of these ew and el is previously described as shown in Fig. 8B. I remember as. In data item 1, No.1 to No. Select a number from 5 and set it.

Data items 2 to 6 of FIG. 8A show data about the number and length of needles of the parts constituting the button trimming as shown in FIG. 9A. That is, data item 2 is the total length of the sewing thread (m1), data item 3 is the number of needles (ln) on both sides of the parallel part (h2), data item 4 is the number of needles (en) around the eyelet part (h1), Data item 5 is a mes space of the parallel part h2 (ls of FIG. 9), and data item 6 is a mes space of the eyelet part h1 (es of FIG. 9).

Data item 7 relates to the size of the straight latch sewing (w4). The size of the straight bar sewing w4 is defined by the horizontal width cl and the vertical length cw, and the combination of cl and cw is previously stored as the table t3 as shown in Fig. 8 (c). In data item 7, a number is selected from No. 1 to No. n in the table t3.

Data item 8 sets whether or not to perform the second bobbin thread shown in Fig. 11 to be described later. Data item 9 sets whether or not to perform the fourth bobbin thread. These are described later in detail.

In the sewing machine 10, the size or shape of the sewing to be formed can be called out on the operation panel 150 and set.

The operation panel 150, which is a selecting means of the present invention, has a preparation key 151, a pattern number selecting portion 152, a data item selecting portion 153, a data value setting portion 154, and a data setting switch (Fig. 10). 155).

The pattern number selector 152 is for selecting a pattern number, and the pattern number currently selected is displayed on the pattern display unit 152a ("1" in FIG. 10). Other pattern data can be selected by changing the numbers one by one within the range of 1 to 9 by the + key 152b and the-key 152c under the pattern display unit 152a.

The data item selector 153 selects data items in the pattern data selected by the pattern number selector 152. The data item currently selected is displayed on the item display unit 153a ("1" in Fig. 10). Other data items can be selected by changing the numbers one by one within the range of 1 to 9 by the + key 153b and the-key 153c under the item display unit 153a.

When a data item is selected in the data item selection unit 153, a number set in advance for the data item is displayed on the value display unit 154a of the data value setting unit 154. The value can be changed by increasing or decreasing the number of the value display unit 154a by a predetermined interval within a predetermined range by the + key 154b and the-key 154c under the value display unit 154a.

The data setting switch 155 is a switch to operate when performing data setting work. In other words, when the data setting switch 155 is pressed, it is possible to change the data value. The selection or change of each item or number is determined by pressing the data setting switch 155 again.

The preparation key 151 is a switch for creating seam data corresponding to the data value set after completion of the setting operation.

Next, the operation of the knitting machine 10 having the above configuration will be described based on the flowchart of FIG.

This general flow starts, for example, when the main power supply (not shown) of the sewing machine 10 is turned ON. In addition, it is assumed that the sewing material F is previously set at a predetermined set position.

First, in step S1, it is determined whether the preparation key 151 has been operated. If it is not operated, this determination is repeated, and if it is operated, seam data is created in step S2. The creation of the seam data is data generated for driving a drive source such as the main shaft servomotor 117 based on the data contents of the selected pattern data, such as needle drop data for determining the needle drop position of the sewing needle 18. It contains data.

Next, in step S3, the transfer table 13 is moved from the set position to the home position.

Next, in step S4, it is monitored whether the start switch 134 is in the ON state, and when it is turned on, the process proceeds to step S5. In step S5, the cloth cutting motor 133 drives the receiving tray 33 to form the buttonhole H, and then moves the feed table 13 to the sewing start position in step S6. A process is performed.

Subsequently, in step S7, the main shaft servo motor 117, the X-axis pulse motor 119, the Y-axis pulse motor 123, and the Z-axis pulse motor 126 are driven to sew a button on the basis of the seam data. In step S8, trimming ends. At this time, the transfer table 13 is in the sewing end position almost the same as the sewing start position.

At the end of the sewing, the return spring 92 is turned off and the looper supporting portion 70 rotates 180 degrees from the origin position, and the crimping portion (c) with respect to the protrusion 28c of the upper thread cutting blade 28 is used. 95) overlap in the vertical direction.

Subsequently, the return spring 92 is turned on in step S9, and the crimping portion 95 pushes the protrusion 28c downward through the upper thread cutting link 93 and the upper thread cutting drive shaft 94 so that the upper thread cutting blade 28 The upper thread is cut by At the same time, the operating lever 85 is pushed by the driving force of the return spring 92 as described above, and the lower thread pulling plate 84 rotates. As a result, the plate offset plate 74 moves upward, and the plate offset piece 74b enters between two plates of the seal tension portion 76c, and the lower thread 38 is not tensioned, and the lower thread pull plate 84 The lower thread 38 is pulled from the side where the thread is felt by the lower thread pulling portion 84b (first pull).

After the lower thread 38 is pulled out, the return spring is turned off, and the upper thread cutting blade 28 returns to the cutting standby position by the force of the return spring 81, and the drive transmission member 99 is in the initial state. It returns to the top dead center of, and the lower thread pulling device 80 returns to the initial state by the negative force of the return spring 81.

Next, in step S10, the transfer table 13 starts to move to return to the home position from the sewing end position. The movement of this feed table 13 takes time until immediately before the lower thread cutting operation of step S15 described later.

In addition, in step S11, the looper support part 70 located in the rotational position of 180 degrees returns 45 degrees in the origin direction. Accordingly, the lower thread 38 and the examination 34 are divided up and down by the ends (not shown) of the needle plate 19 to cut the lower thread.

Subsequently, in step S12, it is determined whether or not a second bobbin thread is pulled before the bobbin thread cutting according to the setting of data item 8 of the table t1.

Data item 8 can be set for the following reasons. As described above, the amount of movement of the feed table 13 from the home position to the sewing end position varies depending on the length of the buttonhole H (the ml value), and is shorter by longer and longer by shorter. Therefore, the distance for returning to the origin position of the conveyance stand 13 starting from step S10 changes with the length of the button | hole hole H (the said ml value). Moreover, the lower thread 38 is also tensioned with the sewing material F in the state fixed to the cloth press part 36 by the movement of the conveyance stand 13. However, since the lower thread 38 is released in step S9, when the amount of movement of the transfer table 13 is not so long, even if the sewing material F to which the lower thread 38 is connected is moved by the lower thread 38, There is no case. In addition, if the movement amount is short, the consumption amount of the lower thread 38 at the time of cutting the lower thread in step S15 is also supplied, and there is no strong tension or the cloth side being tensioned on the lower thread 38 after cutting.

However, when the amount of movement of the transfer table 13 is large, that is, when the ml value in sewing of step S7 is short, the movement amount of the transfer table 13 starting from step S10 becomes long, and the amount of pulling of step S9 is insufficient. . Therefore, when the sewing length is short, the worker sets "Yes" for the lower thread pulling of the data item 8. If "YES" is present for the data item 8 in step S12, the return spring 92 is turned ON in step S13, and the lower thread 38 is attracted by the lower thread pulling device 80, and then it is loosened by turning OFF continuously. Go to S14. Thus, by pulling the lower thread 38 in step S13, it becomes possible to cope with the consumption at the time of conveyance of the transfer table 13 and the cutting of the lower thread in the next step.

If the movement amount of the conveyance table 13 is not so large and "none" is set for the data item 8, the process does not proceed from step S12 to step S13, that is, the process proceeds to step S14 without pulling the lower thread.

In step S14, the return spring 92 is turned on, and the lower thread pulling plate 84 is rotated in a clockwise direction in Fig. 5, whereby the lower thread 38 is pulled and tensioned. In this stretched state, the process proceeds to step S15.

In step S15, the lower thread cutting cylinder 30 is turned on in the lower thread cutting device 37 in the standby state of FIG. 2, whereby the movable blade 50 is examined by the recesses 50a and 50b, respectively. ), And rotates counterclockwise while capturing the lower thread 38. When the moving blade 50 approaches the fixed blade 44, the operating portion 65 of the thread holder opener 64, which has been rotated together with the movable blade 50, pushes down the thread holding pin 62 downward. The fixing means 55 clamps the screen 34 and the lower thread 38, respectively. Immediately after the clamp, the moving blade 50 contacts the fixed blade 44, and the screen 34 and the lower thread 38 are cut.

Subsequently, at step S16, the return spring 92 is turned off, and the lower thread pulling plate 84 which has tensioned the lower thread 38 returns to the standby position, whereby the lower thread 38 is loosened (third). . Thereafter, the lower thread cutting cylinder 30 is turned OFF in step S17, and the movable knife 50 and the thread holder opener 64 are rotated clockwise to return to their original positions. While the thread catching pin 62 is pushed down, the fixing means 55 (a clamping member) is in a state capable of releasing the lower thread 38 for a moment, but the lower thread 38 is loosened and thus does not come out of the fixing means 55.

Next, in step S18, the cloth pressing portion 36 which pushes the sewing material F to the feed table 13 is raised, and the rotation angle is reversed by turning the looper supporting portion 70 by approximately 135 degrees. Return to.

In addition, the transfer table 13 is moved to a set position for the next sewing in step S19. At this time, the lower thread 38 is moved together with the feeder 13 by being clamped to the fixing means 55 fixed on the feeder 13, and the lower thread 38 is tensioned from the looper part 20 side at this time. However, since it becomes loose at step S16, the lower thread 38 is not excessively tensioned or released from the fixing means 55.

In step S20, it is determined whether the fourth bobbin thread is to be pulled in accordance with the setting contents of the data item 9. If the data item 9 is "YES", the process proceeds to Step S21, where the return spring 92 is driven to pull the bobbin thread, and then the process ends. If it is determined in step S20 that the data item 9 is set to "none", this process is terminated as it is.

This data item 9 sets whether or not to pull the lower thread in consideration of the movement amount of the feed table 13 during the next sewing. That is, at the start of sewing, it moves from the set position to the origin position, and then from the origin position to the sewing start position (steps S3, S6 in Fig. 11). The amount of movement from the set position to the origin position is basically constant, but the movement from the origin position to the sewing start position is changed by the sewing length (ml value) as described in data item 8, and the fixing means 55 on the feed table 13 ), The degree of tension of the lower thread 38 clamped in the) is also changed. Therefore, the worker considers the next process to be "Yes" for the data item 9 if the sewing length is short and the moving amount is long. do.

In addition, in step S13, S14, S21, the return spring 92 is turned ON and the lower thread is pulled, but in step S11, the looper support part 70 rotates by 45 degrees, after which the looper support part 70 rotates by 180 degrees. Since the upper thread cutting blade 28 does not perform the upper thread cutting operation.

The determination in step S12 is a value that is the source of the movement amount of the feed table 13 in step S10, not according to the setting contents of data item 8, and is automatically determined by the CPU 111 based on the sewing length (ml) value. You may also In this case, the reference value A is set in advance, and the second lower thread pulling is performed when ml <A compared to the sewing length ml value.

The determination in step S20 is not based on the setting contents of the data item 9, but the sewing length (ml) value is used as a source of the amount of movement from the origin position of the transfer table 13 to the sewing start position at the start of the next process. The CPU 111 may automatically discriminate the basis. Also in this case, the reference value B is set in advance, and the fourth lower thread pulling is performed when ml <B compared with the sewing length (ml) value.

In this way, it is convenient to configure automatic discrimination.

According to the above-mentioned sewing machine 10, first, as shown in FIG. 11, the lower thread 38 is dragged by the lower thread pulling plate 84 at step S14, and the lower thread 38 is removed by the lower thread cutting device 37 in this state. After cutting, the lower thread pulling plate 84 is returned to its original state, the lower thread 38 is loosened, the lower thread cutting device 37 is turned off, and the movable scalpel 50 and the thread holder opener 64 are rotated to their original positions. At this time, the clamp of the lower thread 38 is released by the operating part 65 for a moment. However, since the lower thread 38 is loosened, it does not escape from the fixing means 55.

In other words, the lower thread 38 is loosened before the clamp is released after cutting the lower thread, so that the lower thread 38 is not released from the fixing means 55 (the pinching member) even when the type of the lower thread or the load on the thread supply side becomes large, This does not bounce and can form a smooth and good seam seam.

In addition, since the lower thread 38 is in a tensioned state by the lower thread pulling plate 84, the lower thread 38 may be easily tensioned to some extent. In addition, the lower thread pulling of steps S13 and S21 is performed based on the contents of data item 8 and data item 9 set through the operation panel 150 in consideration of the movement amount of the transfer table 13, so that the lower thread 38 is sufficiently dependent on the movement amount. This tension can be prevented from being applied to the lower thread 38 when the transfer table 13 moves.

In particular, if excessive tension is not applied before cutting the lower thread 38 by step S13, the lower thread 38 can be reliably loosened even when the fixing means 55 after cutting is released. In addition, the fact that excessive force is not applied to the lower thread 38 clamped by the fixing means 55 in step S21 means that the clamping force of the fixing means 55 may be weak and the size of each member constituting the fixing means 55 is reduced. Is possible.

<Example>

In the above embodiment, one of the pattern data is selected for the data items 8 and 9 and set and selected as the data in the selected pattern data. However, as shown in Figs. 12 and 13, the memory switch is set as the sewing condition irrespective of the pattern. It may be set.

FIG. 12A shows an operation panel (selection means) 200 as another example of the operation panel of the knitting machine according to the present invention. FIG. 12B shows a table t4 indicating the contents of the memory switch number set by the operation panel 200. This table t4 is stored in the ROM 112, for example.

The operation panel 200 is composed of a preparation key 201, a memory switch number selection unit 202, and a data value setting unit 203.

The preparation key 201 is a switch for entering the memory switch setting mode and a memory for storing contents set in the memory switch setting mode.

The memory switch number selection unit 202 selects a memory switch number, and the memory switch number currently selected is displayed on the memory switch number display unit 202a. Another memory switch number can be selected by changing the numbers one by one within the range of 1 to 8 by the + key 202b and the-key 202c under the memory switch number display section 202a.

The data value setting section 203 is for setting the memory switch value selected by the memory switch number 202, and the data value currently set on the value display section 203a is displayed. By operating the + key 203b and the-key 203c under the value display unit 203a, the value can be changed by increasing or decreasing the number of the value display unit 203a at predetermined intervals within a predetermined range.

The contents of the memory switch are, for example, related to the speed and the amount of movement in the Y feed direction at the time of thread cutting. 1 ~ No. Since 6 is conventionally known, description is omitted in the present invention.

Memory switch No. 7 sets whether or not to perform the second bobbin pull (FIG. 11, step S13) similarly to the data item 8 of the table t1. It is to set whether or not to pull the lower thread (FIG. 11, step S21). In either case, "1" is set. If not, "0" is set.

13 is a flowchart of the setting processing in the memory switch setting mode. This processing starts by turning on the power while pressing the preparation key 201.

When this processing starts, in step J1, "1" is displayed in the memory switch number display section 202a. Subsequently, in step J2, it is determined whether the + key 202b and the -key 202c have been operated. In operation J3, the display contents of the memory switch number display section 202a are updated one by one according to the operation, and the process proceeds to step J4. do. If it is determined in step J2 that no operation has been made, the process proceeds to step J4. In addition, in accordance with the display of the memory switch number display section 202a, the standard value for each number is displayed on the value display section 203a of the data value setting section 203.

In step J4, it is determined whether the + key 203b and the-key 203c of the data value setting unit 203 have been operated. In operation J5, the display content of the value display section 203a is updated for each predetermined unit in accordance with the operation of step J4, and the process proceeds to step J6. If it is determined in step J4 that no operation has been performed, the process proceeds to step J6.

In step J6, it is determined whether the preparation key 201 has been operated. If it is not operated, the process returns to step J2. If so, EEPROM (Electrically Erasable Read) not showing the contents of the memory switch set in steps J2 to J5 in step J7. Only Memory) to complete this process.

In addition, this invention is not limited to the said embodiment, A concrete shape, a structure, etc. can be changed suitably.

For example, the seal tension portion 76c may be configured as a so-called active tension electrically controlled by using a solenoid or the like, and in that case, the next sewing may be made open at the end of sewing in step S8 shown in the flowchart of FIG. You may leave it open until it starts.

According to the invention of claim 1, the lower thread pulling means first performs the predetermined operation from the initial state and pulls the lower thread, and in this state, the lower thread is clamped by the clamping member, and the lower thread is cut by the lower thread cutting device. Subsequently, the lower thread pulling means is returned to its original state, and the lower thread is loosened, and then the clamping member is brought into a state where the lower thread can be released by the release member. At this point, the lower thread is loosened and is not loosened by the clamping member.

In other words, the lower thread is loosened before the fixing means is released, so even if the type of the lower thread or the load on the thread supply side is large, the lower thread is not released from the clamping member, and in the next fixed sewing, a smooth good overlock seam is formed because the oar does not bounce. can do.

In addition, the lower thread is pulled by the lower thread pulling device before cutting, so that the lower thread has a certain amount of tension and can be easily cut.

According to the invention described in claim 2, it is possible to select whether the lower thread is pulled or loosened by the lower thread pulling device before the lower thread cutting by the selecting means. Therefore, when the lower thread consumption is large, by selecting the lower thread pull by the selection means it is possible to prevent the excessive tension on the lower thread when moving the conveyer. In addition, when the amount of movement of the bobbin thread is small and the consumption of the bobbin thread is small, if it is selected so as not to be pulled by the selecting means, unnecessary bobbin pulling is not performed and the bobbin thread can be prevented from loosening more than necessary.

According to the invention described in claim 3, the same effects as in claim 2 can be obtained, and the automatic determination is more convenient.

According to the invention set forth in claim 4, when the amount of movement of the conveyance from the origin position to the sewing position at the start of sewing is long, the lower thread held by the fixing means of the lower thread cutting device on the conveyance is also consumed. According to the invention described in claim 4, it is possible to select whether the lower thread is pulled or loosened by the lower thread pulling device for the next sewing by the selecting means. Therefore, when the amount of lower thread consumption due to the movement at the next sewing start is large, the thread is pulled in advance by selecting the lower thread pull by the selection means, and it is possible to prevent excessive tension on the lower thread during the movement of the next sewing carriage. have. The fact that the excessive force is not applied to the lower thread may be a weak clamp force by the clamping member, and miniaturization of each member constituting the clamping member is possible.

When the amount of movement is short and the consumption of the bobbin thread is small, if it is selected so as not to be pulled by the selecting means, unnecessary bobbin pulling is not performed and the bobbin thread can be prevented from loosening more than necessary.

According to the invention described in claim 5, the same effects as in claim 4 can be obtained, and the convenience is further improved from automatic determination.

Claims (5)

A looper device disposed in the bed so as to face the needle rod disposed on the arm of the sewing machine frame, the looper device operating in synchronization with the needle rod; A lower thread pulling device comprising a lower thread pulling means for loosening the lower thread by returning to the original state after pulling the lower thread, and a lower thread pulling driving means for driving the lower thread pulling means; A transfer table which is disposed on the upper surface of the bed part and which the sewing material is placed to move at least between the origin position and the sewing position; A mobile thread disposed on the transfer table for cutting the bobbin thread, a bobbin member for pinching the bobbin thread from the bobbin cutting to the cutting of the bobbin thread, and a bobbin thread for the clamping member to be inserted into or pulled out of the bobbin member before or after bobbin cutting. Equipped with a cutting device, In a sewing machine for sewing a sewing thread by cooperation of a needle bar and a looper device, and then cutting the lower thread by a lower thread cutting device, When the lower thread is cut, the lower thread is cut by the lower thread cutting device in a state where the lower thread is clamped by the clamping member, and then the lower thread is cut by the release member. A sewing machine, characterized in that for returning the lower thread pulling means to the original state through the lower thread pulling drive means before being released. The method of claim 1, The transfer table is to move from the sewing position to the home position after the end of sewing and before cutting the lower thread. A sewing machine for knitting, characterized in that a selection means for selecting whether to pull or loosen the lower thread by the lower thread pulling device is arranged before cutting the lower thread. The method of claim 1, The transfer table is to move from the sewing position to the home position after the end of sewing and before cutting the lower thread. A sewing machine for sewing, characterized in that it is determined automatically according to the length of movement from the sewing position to the origin position, whether the lower thread is pulled or loosened by the lower thread pulling device immediately before cutting the lower thread. The method of claim 1, At the start of sewing, the transfer table is moved from the origin position to the sewing position, and after selecting the means for selecting whether to pull or loose the lower thread by the lower thread pulling device for the movement of the transfer table at the next sewing start after cutting the lower thread. Crochet sewing machine characterized by the arrangement. The method of claim 1, At the start of sewing, the transfer table is moved from the origin position to the sewing position, and at the next sewing start after cutting the lower thread, the origin of the next sewing is pulled or loosened by the lower thread pulling device for the movement of the carriage. Sewing machine, characterized in that automatically determined according to the moving length from the position to the sewing position.