JP2009160263A - Buttonhole sewing machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a buttonhole sewing machine capable of performing sewing while suppressing coming off of a core thread. <P>SOLUTION: The buttonhole sewing machine includes a vertical movement mechanism 20 which moves a needle bar vertically, a needle swing mechanism 30 which swings the needle bar, a looper mechanism 40 which forms stitches in a cloth to be processed in cooperation with the needle bar, a movement mechanism 70 which moves the cloth to be processed along a horizontal plane, a core thread guiding means 90 which guides the end of the core thread between zigzag stitches, storage means 107 which stores sewing data for forming buttonhole stitches, and control means 100 for controlling the formation of the buttonhole stitches around a button hole on the basis of the sewing data. The control means controlling the formation of a core thread holding section H where sewing is performed by reducing the width of at least one of the needle swing width of the needle bar or a stitch pitch along the button hole to be narrower than in the other sewing sections, at a sewing start end portion. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a buttonhole sewing machine which performs a hole stitching using a core thread.

A conventional buttonhole sewing machine includes a needle bar provided with a sewing needle, a needle swinging mechanism that swings the needle bar to the left and right, a looper mechanism that is arranged to face the lower side of the needle bar, and the needle bar is moved up and down. Vertical movement mechanism, cloth feed mechanism for holding the cloth and feeding it in the front / rear / left / right direction, a turning mechanism for turning the needle bar and the looper, a cloth cutting mechanism for forming a button hole in the cloth, a needle swinging mechanism and a looper A sewing machine motor that drives the mechanism and the vertical movement mechanism is provided.
Further, the cloth feed mechanism has an X-axis pulse motor that moves left and right and a Y-axis pulse motor that moves back and forth, and the turning mechanism has a turning pulse motor.
And, in order to control the cloth feed mechanism and the turning mechanism, it is possible to sew various shapes by setting the hole shape, the boring length, the number of stitches, etc. as pattern data for the sewing shape. Yes. At the time of sewing, the cloth feed mechanism and the turning mechanism are controlled by the stitch data for each stitch calculated from the setting contents of the pattern data.
In addition, a plurality of the above pattern data is stored, and if the pattern data is set in advance, it is possible to carry out the drilling of different shapes only by selecting the pattern No. (for example, patent document) 1).
In addition, when buttonhole sewing is performed, there is a case where a core thread is supplied between two stitches of needle swing and a core thread is sewn. In such sewing, a supply means for supplying the core thread is provided between the needle drop positions on both sides of the needle swing, and the needle thread is advanced zigzag while performing needle drop on both sides of the core thread. Sewing is performed so that the core thread is sandwiched between the seam of the upper thread and the cloth (for example, see Patent Document 2).
JP 2000-316171 A JP 2005-304620 A

However, there is a problem that the core thread is pulled out from the sewing start end due to the needle thread / looper thread, the material of the core string, and the overlock stitching width, and the sewing cannot be performed well. In particular, when the core thread or the upper thread is a slippery material, or when the overlock stitching width or the sewing pitch is wider than the thickness of the core thread, the problem is remarkable.
An object of the present invention is to appropriately sew a core thread.

  According to the first aspect of the present invention, there is provided a needle bar for holding a sewing needle in which an eye thread for inserting an upper thread is formed, a vertical movement mechanism for moving the needle bar up and down, and a length of a button hole formed in a work cloth. A needle swinging mechanism that swings the needle bar in a direction that intersects the direction, a looper mechanism that forms a seam on the work cloth in cooperation with the needle bar, and a direction perpendicular to the vertical direction of the sewing needle. A moving mechanism for moving the core thread, a core thread guide means for guiding the end of the core thread supplied from the core thread supply source between the needle swing seams formed by the needle swing of the needle swing mechanism, and a button hole Storage means for storing sewing data for forming buttonhole stitches having at least left and right side stitches around the periphery, and controlling each of the mechanisms based on the sewing data, so that the holes are formed around the buttonholes. Control means for forming seams; In the buttonhole sewing machine, the control means sews at the sewing start end with at least one of the needle swing width of the needle bar or the sewing pitch along the buttonhole being narrower than the other sewing sections. Control for forming a core yarn holding section is performed.

  The invention according to claim 2 has the same configuration as that of the invention according to claim 1, the sewing data includes position information indicating each needle drop position of the core thread holding section, and the control means The seam of the core thread holding section is formed according to the sewing data.

  The invention described in claim 3 has the same configuration as that of the invention described in claim 2, and further includes position setting means for setting position information indicating each needle drop position of the core yarn holding section.

  The invention according to claim 4 has the same configuration as that of the invention according to claim 1, and the control means applies to sewing data that does not include position information indicating each needle drop position of the core yarn holding section. Then, control is performed to perform sewing by converting to the sewing having the core thread holding section.

  Invention of Claim 5 is provided with the structure similar to the invention as described in any one of Claim 1 to 4, and the area setting means which sets the number of needles of the said core yarn holding | maintenance area, or area length. It is characterized by that.

  According to the first aspect of the invention, the edge stitching is performed around the button hole with the needle swing width and the sewing pitch determined according to the sewing data. In this case, the control means performs sewing at the sewing start end by narrowing at least one of the needle swing width of the needle bar or the sewing pitch along the button hole as compared with the other sewing sections. In addition, one or both of the needle swinging mechanism and the moving mechanism are controlled to form the core yarn holding section. As a result, it is possible to form a narrower needle swing seam and a plurality of needle swing seams formed more densely in the cloth feed direction at the sewing start end, and the sewing start end of the core thread is more It becomes possible to hold firmly and make it difficult to come off. For this reason, even if the core thread or upper thread is a slippery material, or even when the over-width stitching width or sewing pitch of the normal sewing section is wider than the thickness of the core thread, the core thread is removed. Can be more effectively reduced, and proper buttonhole sewing can be performed.

  According to the second aspect of the present invention, by including position information indicating each needle drop position in the core thread holding section in the sewing data, at least one of the needle swing width of the needle bar or the sewing pitch along the button hole is different. Narrower than the sewing section is realized. For this reason, the core thread can be prevented from being pulled out by software processing such as setting and correction of sewing data, and there is no need to change the design or add a new configuration to each mechanism of the sewing machine. Therefore, it is possible to easily realize proper buttonhole sewing with reduced stitches.

  Since the invention according to claim 3 includes position setting means for setting position information indicating each needle drop position in the core thread holding section, it is possible to arbitrarily set the overlock stitching width and the sewing pitch in the core thread holding section. . Accordingly, it is possible to set an appropriate core yarn holding section for various core yarns or for various hole stitching patterns.

According to a fourth aspect of the present invention, for the sewing data in which the setting of the core thread holding section is not performed, the control means automatically converts the sewing data to the sewing having the core thread holding section and performs the control for sewing. Therefore, it is possible to perform the sewing of the core yarn holding section while eliminating the need for setting the core yarn holding section and the data for performing the sewing of the core yarn holding section.
Note that “the control means automatically performs control to perform sewing by converting to sewing having a core thread holding section” means that, for example, the control means has a normal sewing section for a predetermined number of stitches to start sewing. For example, there is a control in which sewing is performed at a predetermined ratio with respect to the needle swing width or the sewing pitch, or sewing is performed with the needle swing width or the sewing pitch reduced by a predetermined width.

Since the invention according to claim 5 includes section setting means for setting the number of needles or section length of the core yarn holding section, the number of stitches of the core thread holding section can be arbitrarily determined, and as a result, the core It is possible to arbitrarily adjust the holding force of the yarn end portion, and it is possible to set an appropriate core yarn holding section when using various core yarns or various hole sewing patterns.
Here, the “section length” refers to the length of the core yarn holding section in the direction in which the sewing proceeds in a direction orthogonal to the needle swinging direction.
In the case of the invention according to claim 5 that depends on claim 2 or 3, the position information already included in the sewing data and the number of stitches or section length of the core yarn holding section set by the section setting means It is also possible to select one of these and make it possible to execute the sewing of the core yarn holding section.

(Overall configuration of the embodiment)
A buttonhole sewing machine 10 according to an embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a side sectional view of the buttonhole sewing machine 10, and FIG. 2 is a side view seen from the opposite side of FIG.
As shown in FIG. 1, the buttonhole sewing machine 10 includes a bed portion 2 a that is located at the lower part of the entire sewing machine and has a substantially rectangular box shape, and a vertical body portion 2 b that is provided at one end of the bed portion 2 a. The sewing machine frame 2 includes an arm portion 2c that extends from the vertical trunk portion 2b in the same direction as the bed portion 2a. In the following description, the direction in which the vertical body portion 2b is erected is the Z-axis direction, the longitudinal direction of the bed portion 2a and the arm portion 2c is the Y-axis direction, and the Y-axis direction is perpendicular to the Z-axis direction. The direction orthogonal to both the Z-axis directions is taken as the X-axis direction.

  The buttonhole sewing machine 10 intersects with the needle bar 12 that holds the sewing needle 11 through which the upper thread is passed, the vertical movement mechanism 20 that moves the needle bar 12 up and down, and the longitudinal direction of the buttonhole formed in the work cloth. A needle swinging mechanism 30 that swings the needle bar 12 in the direction, a looper mechanism 40 that forms a seam of over stitching on the work cloth in cooperation with the needle bar 12, and a looper base 47 of the needle bar 12 and the looper mechanism 40. A turning mechanism 60 for turning, a moving mechanism 70 for placing and holding the work cloth on the cloth base 71 and moving in the X and Y axis directions, a cloth cutting mechanism (not shown) for forming a button hole in the work cloth, a core Core thread guide means 90 for guiding the thread from a needle thread supply source (not shown) to a needle drop position divided on both sides by swinging of the sewing needle 11, a thread cutting mechanism (not shown) for cutting each thread after completion of sewing, and sewing Data as data Based on Ndeta and an operation control unit 100 (see FIG. 4) as a control means for forming a darning stitches around the buttonhole by controlling the respective mechanisms.

(Needle bar)
As shown in FIG. 1, the needle bar 12 is supported by a metal 14 held by a thin disc-shaped plate spring 13 provided at the upper end of the arm 2c. The plate spring 13 is disc-shaped and its outer periphery is held by the arm portion 2c. A metal 14 is disposed at the center position of the leaf spring 13. The metal 14 has a cylindrical shape and is held by the leaf spring 13 with its center line oriented in the Z-axis direction when no external force is applied.
The needle bar 12 has a round bar shape and is inserted into the metal 14. The needle bar 12 is supported by the metal 14 so as to be slidable along the longitudinal direction and rotatable about an axis along the longitudinal direction. Further, since the metal 14 is held at the center of the plate spring 13 as described above, the needle bar 12 inserted into the metal 14 moves the position of the metal 14 within the range allowed for the bending of the plate spring 13. As a center, the lower end portion can be inclined in any direction perpendicular to the Z-axis direction.
Further, the needle bar 12 can hold the sewing needle 11 at the lower end portion thereof and can guide the upper thread by making the inside hollow from the upper end portion to the vicinity of the lower end portion. A stitch hole is formed in the sewing needle 11, and an end portion of the upper thread guided through the inside of the needle bar 12 is inserted.

(Vertical movement mechanism)
As shown in FIG. 1, the vertical movement mechanism 20 is rotated at an increased speed from the upper shaft 21 by an upper shaft 21 rotated by a timing belt (not shown) by a sewing machine motor 3 as a servo motor and large and small gear trains 22 and 23. , A rod 26 having one end connected to the needle bar drive shaft 24 via an eccentric cam 25, and a vertically moving arm 27 having one end connected to the other end of the rod 26. A bifurcated member 28 provided at the other end of the vertically moving arm 27 and a ring 29 for connecting the bifurcated member 28 and the needle bar 12 are provided.

  Both the upper shaft 21 and the needle bar drive shaft 24 are disposed along the X-axis direction and are rotatably supported within the sewing machine frame 2. A rotational force is transmitted from the upper shaft 21 to the needle bar drive shaft 24 at twice the rotational speed by the gear trains 22 and 23.

  The vertical movement arm 27 is pivotally supported in the sewing machine frame 2 by a support shaft along the X-axis direction at an intermediate position in the longitudinal direction. Then, the rotational motion of the needle bar drive shaft 24 is converted into a reciprocating motion by the rod 26 and the eccentric cam 25 and transmitted to one end portion of the vertical movement arm 27, and both end portions swing along the substantially Z-axis direction. It is possible to make it.

The other end of the vertical movement arm 27 is connected to the needle bar 12 by a bifurcated member 28 and a ring 29.
The bifurcated member 28 moves forward and backward along the extending direction (substantially Y-axis direction) of the other end of the vertical moving arm 27 with respect to the vertical moving arm 27 and the extending direction of the other end of the vertical moving arm 27. It is supported so as to be able to rotate around the axis.
The ring 29 moves linearly along the direction perpendicular to the extending direction (substantially Y-axis direction) of the other end of the vertical movement arm 27 with respect to the bifurcated member 28 and in the extending direction of the other end of the arm 27. It is supported so as to be able to rotate about an orthogonal direction as an axis.
The ring 29 is connected to the needle bar 12 while being sandwiched between two collars 29 a fixed to the needle bar 12 with the needle bar 12 inserted therethrough. Rotating around is possible.
With this configuration, even when the needle bar 12 is tilted in any direction allowed by the metal 14, or even when the needle bar 12 is rotated about its own longitudinal direction, It is possible to apply a reciprocating vertical movement force from the vertical movement arm 27.

(Needle swing mechanism)
As shown in FIG. 1, the needle swing mechanism 30 includes an outer peripheral cam 31 provided on the upper shaft 21, a rod 32 that swings in contact with the outer periphery of the outer peripheral cam 31, and the vicinity of the swing end of the rod 32. A link 33 that is connected and provided with a reciprocating motion, an L-shaped arm 34 that is connected to the link 33 and rotates, a link 35 that is connected to the L-shaped arm 34 and is provided with a reciprocating motion up and down, and a link 35, a slider 36 to which a reciprocating motion in the vertical direction is transmitted from 35, a slide guide shaft 37 that allows the slider 36 to reciprocate only along the Z-axis direction, and a swing that moves along the X-axis direction according to the height A stand 38 is provided.

The outer circumferential cam 31 gives the rod 32 a reciprocating rocking motion of one stroke along the Y-axis direction per one rotation of the upper shaft 21.
The rod 32 transmits the reciprocating motion along the Y-axis direction to the L-shaped arm 34 via the link 33, and the L-shaped arm 34 converts the reciprocating motion direction to the Z-axis direction to the slider 36 via the link 35. introduce.
The slider 36 supports a swing table 38 so as to be rotatable about the Z axis, and the swing table 38 also moves up and down as the slider 36 moves up and down.

The oscillating base 38 supports the needle bar 12 so that the needle bar 12 can be moved up and down with the vicinity of the lower end of the needle bar 12 inserted, and on both outer side surfaces between the Z-axis direction and the X-axis direction. An inclined guide groove is formed. The swing base 38 is sandwiched between convex portions (not shown) that fit into the guide grooves from both sides thereof. When the swing base 38 moves in the vertical direction, the swing base 38 is skewed along the guide grooves. No. 38 is moved in the X-axis direction to perform needle swing.
As described above, since the needle bar drive shaft 24 rotates at twice the speed of the upper shaft 21, the needle bar 12 moves up and down twice when the swing base 38 reciprocates once in the X-axis direction. In other words, the needle bar 12 performs needle dropping regardless of the direction in which the needle bar 12 swings in cooperation with the vertical movement mechanism 20 and the needle swing mechanism 30.
In addition, since the convex body (not shown) is supported by a turntable 61 of the turning mechanism 60 described later, the needle swinging direction is also turned at the same time when the needle bar 12 is turned.

(Looper mechanism)
As shown in FIGS. 1 and 2, the looper mechanism 40 oscillates by engaging with a lower shaft 41 rotated by the sewing machine motor 3, a groove cam 42 provided on the lower shaft 41, and the groove cam 42. A spreader swinging arm 43 and a looper swinging arm 44 for performing the above, a spreader driving shaft 45 for moving up and down by the spreader swinging arm 43, and a looper driving shaft 46 as a driving shaft for moving up and down by the looper swinging arm 44. The looper base 47 that is rotatably supported by the sewing machine frame 2 with the drive shafts 45 and 46 disposed at the center position, the needle plate 48 attached to the upper end of the looper base 47, and the lower thread A left looper 49 and a left spreader (not shown) that perform double chain stitching by tying a thread, a right looper 50 and right spreader (not shown) that perform single thread ring stitching with an upper thread, and just below the needle plate 48 At each roux And a mount 53 which supports the 49, 50 and the spreaders.

The groove cam 42 is formed with cam grooves on both surfaces, and each groove cam 42 is individually engaged with the spreader swing arm 43 and the looper swing arm 44 so as to swing at a predetermined timing. .
The spreader swinging arm 43 is pivotally supported by a support shaft facing in the X-axis direction at an intermediate position in the longitudinal direction. One end of the spreader swinging arm 43 is engaged with the groove cam 42 and the other end is engaged with the lower end of the spreader drive shaft 45. Match. That is, the spreader swing arm 43 swings at a predetermined timing determined by the cam groove shape of the groove cam 42 and moves the spreader drive shaft 45 up and down.
The looper swinging arm 44 is pivotally supported by a support shaft facing in the X-axis direction at an intermediate position in the longitudinal direction, with one end engaged with the groove cam 42 and the other end engaged with the lower end of the looper drive shaft 46. Match. That is, the looper swing arm 44 swings at a predetermined timing determined by the cam groove shape of the groove cam 42 and moves the looper drive shaft 46 up and down.

The looper drive shaft 46 is cylindrical, and the spreader drive shaft 45 can be inserted therein. Further, the looper drive shaft 46 is connected to the mounting base 53 via a link at the upper end portion thereof, and by moving up and down, the mounting base 53 is swung so that the loopers 49 and 50 and the spreaders are used. The stitch formation operation is performed.
The spreader drive shaft 45 is cylindrical and is formed so as to penetrate from the lower end portion to the upper end portion, and has a function of guiding the lower thread from the lower end portion to the upper end portion. Further, the spreader drive shaft 45 is connected to a cam (not shown) via a link at its upper end, and by moving up and down, each spreader is swung through the cam to widen the yarn loop. Make it.

The looper base 47 is rotatably supported by the sewing machine frame 2. The looper base 47 is formed in a cylindrical shape, and the spreader drive shaft 45 and the looper drive shaft 46 are inserted into the center thereof.
The upper end portion of the spreader drive shaft 46 extends to the vicinity of the lower part of the mount 53, and the lower thread passed through the spreader drive shaft 45 is guided to a threading hole (not shown) of the left looper 49 through a thread path (not shown). It has come to be.

The left looper 49 and the left spreader perform double chain stitching when the needle swing on the left side of the needle bar 12 is dropped, and the right looper 50 and the right spreader are the needle drop of the right needle swing on the needle bar 12. Perform single-thread ring stitching at the time of sewing.
Accordingly, the left looper 49 and the left spreader are moved in the sewing operation direction in accordance with the needle dropping timing of the left needle swing, and the right looper 50 and the right spreader are sewn in accordance with the needle drop timing of the right needle swing. The movement is applied from the looper drive shaft 46 so that the movement is performed in the movement direction. In addition, each spreader is moved from the spreader drive shaft 45 so that each of the spreaders 49 and 50 moves along with the loopers 49 and 50 so that each looper 49 and 50 expands the yarn loop at a predetermined timing. .

FIG. 3 is a plan view of the needle plate. The needle plate 48 is located at the upper end of the looper base 47 and rotates integrally with the looper base 47. As shown in FIG. 3, a needle hole 48 a is formed in the center portion of the needle plate 48. The sewing needle 11 is inserted into the needle hole 48a, and the loop of the upper thread is supplied to the lower side of the needle plate 48. The loop is entangled with the lower thread by the predetermined swinging operation of the loopers 49, 50 and the spreader, and sewing is performed. . The needle hole 48 a is formed in a long hole shape along the swinging direction of the needle bar 12. Further, since sewing is performed through the needle hole 48a, the lower thread passes through the needle hole 48a and is sewn to the work cloth.
At this time, the core thread is also guided between two needle drop points which are passed through a core thread through hole 48b provided through the side of the needle plate 48 from the side surface to the needle hole 48a and separated on both sides by needle swinging. Can be sewn on the work cloth. That is, the needle plate 48 serves as a part of the core yarn guiding means 90 for guiding the end portion of the core yarn supplied from the core yarn supply source between the needle swing seams formed by the needle swinging of the needle swinging mechanism 30. Also works.

(Swivel mechanism)
For example, when the buttonhole sewing machine 10 performs overlock sewing on a buttonhole having a straight line portion and a drop-like portion of a single character such as an eyelet hole, the buttonhole sewing machine 10 swings along the edge of the hole of the drop-like portion. It is necessary to sew by turning around the needle swinging direction while performing. Therefore, a turning mechanism 60 is provided for turning the needle swinging direction and turning the loopers 49 and 50 and the spreader.
The turning mechanism 60 includes a needle bar pulley 61 for turning the swing base 38 of the needle swing mechanism 30 around the needle bar 12, a looper pulley 62 for turning the looper base 47 of the looper mechanism 40, and these pulleys 61, 62. Is provided with a turning motor 63 (see FIG. 4) that is a pulse motor that is driven to rotate via a timing belt (not shown).

As described above, the swing base 38 is sandwiched between the guide grooves provided on both side surfaces thereof by the convex bodies from both sides, and each convex body is supported by the needle bar pulley 61. Therefore, by turning the needle bar pulley 61, the swinging table 38 is also turned through each convex body, and as a result, the needle swinging direction can be turned.
The needle bar pulley 61 has the swing base 38 loosely inserted into a central through portion whose inside diameter is set to be sufficiently larger than the swing base 38. Therefore, the swing base 38 and the needle bar 12 are prevented from swinging. It is not to become.

The looper pulley 62 is fixedly installed below the looper base 47 and rotates the loopers 49 and 50 and the spreader together with the looper base 47.
The needle bar pulley 61 and the looper pulley 62 are both concentric with the metal 14 and are arranged so as to turn around a common axis parallel to the Z-axis direction.
Then, the turning motor 63 rotates both the needle bar pulley 61 and the looper pulley 62 simultaneously and at the same rotation ratio.

(Movement mechanism)
As shown in FIGS. 1 and 2, the moving mechanism 70 is disposed immediately below the sewing needle 11, and includes a cloth base 71 having a sewing surface on which the work cloth is placed, and the work cloth on the cloth base 71. A cloth presser 76 that holds and presses, a presser cylinder 72 (see FIG. 4) that switches between holding and releasing the cloth presser 76, and an X-axis motor 73 (see FIG. 4) that is a pulse motor that moves and positions the cloth base 71 in the X-axis direction. And a Y-axis motor 74 (see FIG. 4) that is a pulse motor that moves and positions the cloth base 71 in the Y-axis direction.
In the cloth base 71, for example, when performing the stitching of the eyelet hole, the cloth is fed at a predetermined pitch by driving the Y-axis motor 74 at the straight part of the eyelet hole, and at the edge of the hole at the drop-like part. The cloth feed is performed while aligning the needle drop position by the cooperation of the X-axis motor 73 and the Y-axis motor 74 so that the needle drop is performed.

(Thread cutting mechanism)
The thread cutting mechanism includes a movable knife that operates on the upper surface of the bed portion 2a, a fixed knife that slides on the movable knife and is slidably contacted with the movable knife to cut the upper thread, the lower thread, and the core thread. A scalpel cylinder 81 (see FIG. 4), which is an air cylinder for applying a cutting operation to the scalpel, is provided.

(Core yarn guiding means)
The core yarn guiding means 90 is provided near the upper portion of the vertical body portion 2b, and the core yarn fed from a yarn stand portion as a core yarn supply source (not shown) that holds a yarn spool around which the core yarn is wound is used as a cloth. Supply is made between the needle drop positions divided on both sides by the swing of the work cloth C on the table 71.
The core yarn guiding means 90 includes a guide member 91 that guides the core yarn fed from the yarn stand portion from the upper surface to the side surface of the longitudinal body portion 2b, and the core yarn guided by the guide member 91 to the longitudinal body portion 2b. A guide tube 92 is provided for guiding from the base to the vicinity of the looper base 47 in the bed portion 2a. Further, the portion of the core thread passage hole 48b of the needle plate 48 described above also functions as a part of the core thread guide means 90.

The guide member 91 is a bracket provided with a through hole through which the core yarn is inserted, and is fixedly mounted on the side surface of the vertical body portion 2b.
The guide tube 92 is a tubular body having one end opened upward from the vicinity of the longitudinal body 2b on the upper surface of the bed 2a and the other end opened near the looper base 47 in the bed 2a. The guide tube 92 guides by inserting a core thread inside thereof.

(Cloth cutting mechanism)
The cloth cutting mechanism is for forming a button hole in a work cloth, and places a cloth cutting knife for forming a water drop-like cut, a cloth cutting knife for forming a straight cut, and a work cloth. A knife base on which each cloth cutting knife is pressed from above and a cloth cutting motor 83 (see FIG. 4) which is a stepping motor for raising and lowering each cloth cutting knife are provided.
In the above-described cloth cutting mechanism, a drop-shaped cloth cutting knife and a straight cloth cutting knife are used in combination when performing eyelet hole stitching, and a simple buttonhole sewing without a eyelet portion is performed. When performing, only a straight cloth cutting knife is used.

(Buttonhole sewing machine control system)
FIG. 4 is a block diagram showing a control system of the buttonhole sewing machine 10.
The operation control unit 100 stores a ROM 102 that stores programs for executing various kinds of control or processing of the sewing machine, a CPU 101 that executes various programs and performs predetermined processing and control, and stores various types of data when the processing of the CPU 101 is executed. RAM 103 to be used, EEPROM 107 as storage means in which various setting data required for sewing such as pattern data as sewing data are recorded, interface 3b for connecting drive circuit 3a of sewing machine motor 3 to CPU 101, and X-axis motor 73 An interface 73b for connecting the drive circuit 73a to the CPU 101, an interface 74b for connecting the drive circuit 74a for the Y-axis motor 74 to the CPU 101, an interface 63b for connecting the drive circuit 63a for the turning motor 63 to the CPU 101, and a cloth cutting module. An interface 83b for connecting the drive circuit 83a of the printer 83 to the CPU 101, an interface 82b for connecting the solenoid valve drive circuit 82a of the solenoid valve 82 for driving the knife cylinder 81 that is the power of the movable knife for thread trimming to the CPU 101, and a presser. An interface 75b for connecting the solenoid valve drive circuit 75a of the solenoid valve 75 for switching the operation of the cylinder 72 to the CPU 101, and an interface 106 for connecting the operation panel 104, the start switch 105, and the press switch 108 to the CPU 101 are provided.
Further, since the turning motor 63, the X-axis motor 73, the Y-axis motor 74, and the cloth cutting motor 83 are all stepping motors, it is necessary to search for the origin. For this reason, each of the motors 63, 73, 74, 83 is provided with an origin sensor (not shown), and each origin sensor is connected to the CPU 101 via an interface.

The start switch 105 is a switch for executing the start of sewing.
The cloth presser switch 108 is a switch that operates the presser cylinder 72 via the electromagnetic valve 75 so that the cloth presser 76 presses and holds the work cloth on the cloth base 71.

(Pattern data for eyelet hole stitching)
Next, pattern data stored in the EEPROM 107 will be described. The pattern data is sewing data including various kinds of setting information necessary for performing the hole stitching, and pattern data is prepared for each of the plurality of sewing patterns.
Here, based on FIG. 5, various parameters necessary for performing the eyelet hole stitching will be described first.
As shown in FIG. 5 (A), in eyelet stitching, the needle thread is swung so as to surround the button hole B composed of the drop part BT and the straight part BS extending from the tail part of the drop part. When a core thread is used, the core thread is supplied between the needle drop positions on both the left and right sides of the needle swing of the upper thread, and stitching is performed on the needle swing stitch.
Further, the sewing order is as follows. The sewing is started from one side (the right side in FIG. 5A) of the end portion of the straight portion BS of the button hole B opposite to the drop-like portion BT, and the right side of the straight portion BS. Along the right straight section where the sewing is performed along the right side of the tail of the drop-shaped part BT, and the right oblique section where the sewing is performed while being slanted along the right side of the tail of the drop-like part BT, and then along the semicircular shape of the drop-like part BT An arc section where sewing is performed, a left skew section where sewing is performed by skewing along the left side of the tail portion of the drop-like portion BT, and a left straight section where sewing is performed along the left side of the straight portion BS To complete.
Note that the right straight section, the right oblique section, the left straight section, and the left oblique section are all sewn with a uniform needle swing width and feed pitch.
Further, in the buttonhole sewing machine 10, when the operation control means 100 starts the eyelet stitching, at least the sewing swing width of the needle bar 12 or the stitching pitch along the buttonhole B at the sewing start end portion is selected. Either one (here, both) is made narrower than the other sewing sections, and control is performed to form a core thread holding section H in which sewing is performed. In other words, at the sewing start end of the right straight section, which is the start position of the eyelet stitching, the sewing of the core thread holding section H in which the needle swing width and the sewing pitch in the direction along the Y-axis direction are set smaller than each section. Is done.

  As shown in FIG. 5B, the parameters required for the above-described eyelet stitching are the circular side of the drop-shaped portion BT of the button hole B from the sewing start end portion of the first straight section not including the core thread holding section H. The total number of stitches in the total section of the right straight section and right skew section (or left straight section and left skew section) that is the length along the Y-axis direction to the end of The number of needles from the straight part BS of the button hole B in the total section of the right straight section (or left straight section) “Parallel female space ls” which is the distance to the needle drop position on the button hole side in swinging (the same value is adopted for each skew section), and half of the drop-like part BT of the button hole B in the arc section The distance from the circle to the needle drop position on the button hole side when swinging The "eyelet female space es", the "core thread locking stitch length bl" which is the length of the core thread holding section H, and the "number of core thread locking stitches bn" which is the total number of stitches of the core thread holding section H ”And“ core thread snap stitch swing width correction value bw ”which is a difference in needle swing width between the core thread holding section H and other sections. These parameters are determined by inputting numerical values from the operation panel 104.

Further, as shown in the drawing of the drop-like portion BT of the button hole B in FIG. 5C, the width ew and the length el of the drop-like portion are also necessary parameters. As shown in FIG. 5D, these parameters are pre-set with a combination of ew and el sizes. A drop-shaped cloth cutting knife corresponding to the combination is prepared, and a knife number is selected. Thus, the cloth cutting knife is selected and the cloth cutting is performed.
Note that the combination number 0 in FIG. 5D is selected at the time of buttonhole sewing where the width ew and the length el are both 0, that is, there is no drop-like portion BT.

FIG. 6 is an explanatory diagram showing the contents of pattern data stored in the EEPROM 107 described above. Each pattern data includes a knife number (data item 1), a hole length ml (data item 2), a parallel needle number ln (data item 3) and an eyelet needle number en (data item 4). ), Parallel part female space ls (data item 5), eyelet female space es (data item 6), whether or not to perform cloth cutting operation, or before or after sewing (data item 7) and core thread The backtack length bl (data item 8), the number of core thread lock stitches bn (data item 9), and the core thread lock stitch width correction value bw (data item 10) are recorded.
Thus, the pattern data includes, as position information indicating each needle drop position in the core thread holding section H, the core thread stop stitch length bl, the core thread stop stitch number bn, and the core thread stop stitch swing width correction value bw. Are recorded, and the operation control means 100 forms the core yarn holding section H according to these pieces of information.
The items 1 to 10 are individually set and input from the operation panel 104.

(control panel)
FIG. 7 is an explanatory diagram showing the configuration of the operation panel 104. The operation panel 104 displays a data setting switch 104a for switching to or from the input mode for new setting of pattern data or updating of setting contents, and a display for displaying the number of pattern data currently selected in the input mode. A panel 104b, an increase / decrease switch 104c for switching selected pattern data, a display panel 104d indicating the number of the currently selected setting item of the selected pattern data, an increase / decrease switch 104e for switching the setting item, and parameters in the setting item A display panel 104f for displaying the set numerical value, an increase / decrease switch 104g for switching the set numerical value, and a preparation switch 104h for switching from the input mode to the sewing mode in which sewing can be performed.
With the configuration of the operation panel 104, it is possible to input settings for each setting item of pattern data. Since the pattern data is converted into stitch data (described later) indicating each needle drop position for each stitch, the operation panel 104 sets the position information indicating the position information indicating each needle drop position in the core thread holding section H. It will function as a means.
In addition, since it is possible to set the core thread retaining stitch length and the number of core thread retaining stitches of the pattern data from the operation panel 104, the section setting for setting the number of stitches or the section length of the core thread retaining section H is possible. It will also function as a means.

(Seam data)
The stitch data creation process performed by the motion control means 100 will be described.
When pattern data to be sewn is selected by the operation panel 104 according to the processing program in the ROM 102, the CPU 101 expands the stitch data into the RAM 103 from the set contents. FIG. 8 is an explanatory diagram showing stitch data.
As described above, the pattern data is composed of parameters that can be set from the actual size of each part when performing eyelet hole stitching. On the other hand, the CPU 101 controls the drive of the X-axis motor 73, the Y-axis motor 74, the turning motor 63, and the sewing machine motor 3, and when the upper shaft 21 is at a predetermined angle, the CPU 101 controls the X-axis motor 73, the Y-axis motor 74, and the turning motor 63. By driving at a predetermined angle, the needle drop to each needle drop position shown in FIG. Therefore, the CPU 101 converts the pattern data into appropriate stitch data in order to more appropriately control the motors 73, 74, and 63.
That is, the stitch data includes information for determining the operation amounts of the motors 73, 74, and 63 for the total number of stitches for performing a series of eyelet stitches. In FIG. 8, the needle drop on both sides (inner needle and outer needle) in the needle swing is counted as one needle.

For example, as shown in FIG. 8, in a straight section (for example, a section having 3 to 4 stitches), sewing is performed with a fixed stitch swing width by the needle swing mechanism 30, so the drive amount of the X-axis motor 73 is 0, Y The shaft motor 74 is driven at a predetermined feed pitch for every two needles, and the turning amount of the turning motor 63 becomes zero. In this case, the feed pitch by the Y-axis motor 74 is
((Hole length ml)-((Drop width ew) ÷ 2)) ÷ (Number of parallel part needles ln)
Is calculated from

  Further, in the oblique section (for example, the section having 9 to 10 stitches), the X-axis motor 73 is driven every two stitches and the Y-axis motor 74 is driven every two stitches at the same feed pitch as the linear section. The turning amount of the turning motor 63 is zero. Note that the drive amount of the X-axis motor 73 is gradually reduced in accordance with the shape of the drop-shaped portion BT of the button hole B.

  Further, in the arc section (for example, the section of 11 to 18 stitches), the needle drop position on one side of the needle swing moves so as to follow the arc. The turning motor 63 turns by a substantially constant amount for each needle.

Furthermore, in the core yarn holding section (for example, the section having 1 to 2 stitches), the sewing is performed with a width smaller than the fixed needle swing width by the needle swing mechanism 30, so the X-axis motor 73 is set in the direction of canceling the needle swing (reverse) Direction). The drive amount of the X-axis motor 73 at this time is obtained from the core thread snap stitch swing width correction value bw. Further, the Y-axis motor 74 is driven so that a stitch having a predetermined feed pitch smaller than other sections is formed every two stitches. The drive amount of the Y-axis motor 73 at this time is
(Core thread lock stitch length bl) ÷ (Number of core thread lock stitches bn)
Is calculated by

(Explanation of the operation of the eyelet drilling machine)
FIG. 9 is a flowchart showing processing from data setting of the eyelet sewing machine 10 to completion of sewing, and FIG. 10 is a flowchart showing data setting work of the eyelet sewing machine 10 in more detail. The operation of the eyelet hole sewing machine 10 will now be described.
First, the CPU 101 determines whether or not the pattern number increase / decrease switch 104c on the operation panel 104 has been pressed with the main power turned on (step S1). If the switch is pressed, the selected pattern data is changed. Is also changed (step S2).

When the increase / decrease switch 104c is not pressed or when the change of the selected pattern data is completed, the CPU 101 determines whether or not the data setting switch 104a is pressed (step S3). (Step S4).
If not pressed or if the data setting process is completed, it is determined that the preparation switch 104h is pressed (step S5). If not pressed, the process returns to step S1 and is pressed. Then, the process proceeds to the stitch data calculation process (step S6).

Here, the contents of the data setting process will be described with reference to FIG.
When shifting to the data setting process, the CPU 101 first sets the data item number to 1 and displays “1” on the display panel 104d (step S21). In such a state, a female number whose setting item to be set is 1 is selected (see FIG. 6).
Next, the CPU 101 determines whether or not the data item increase / decrease switch 104e is pressed (step S22). If the data item increase / decrease switch 104e is pressed, the CPU 101 increases or decreases the data item number of the display panel 104d according to the increase / decrease input. The set numerical value of the parameter set corresponding to the data item number is displayed on the display panel 104f (step S23).
Then, when the data item increase / decrease switch 104e is not pressed or after the data item number is increased / decreased, the CPU 101 determines whether the increase / decrease switch 104g for increasing / decreasing the parameter setting value has been pressed (step S24). When the button is pressed, the setting value of the parameter displayed on the display panel 104f is increased or decreased according to the selected data item (step S25).
If the increase / decrease switch 104g is not pressed or the numerical value of the parameter is increased or decreased, the CPU 101 determines whether or not the data setting switch 104a is pressed (step S26).
If not pressed, the process returns to step S22. If the button is pressed, the setting content is confirmed and recorded as pattern data in the EEPROM 107, and the data setting process is terminated (step S27).

After the completion of the data setting process or when it is determined in step S3 that the data setting switch 104a has not been pressed, the CPU 101 determines whether or not the preparation switch 104h has been pressed (step S5).
If not pressed, the process returns to step S1, and if pressed, stitch data is created from the selected pattern data (step S6).
In addition, the CPU 101 performs an origin search by each origin sensor of the X-axis motor 73 and the Y-axis motor 74, and aligns the cloth base 71 of the moving mechanism 70 to a predetermined origin position. At the same time, an origin search is performed by the origin sensor of the turning motor 63, and the needle bar and the looper are aligned with a predetermined origin position (step S7). The cutting position by the cloth cutting mechanism and the sewing position by the needle bar are arranged apart from each other in the Y-axis direction. When the cloth base 71 is aligned with the origin position, the work cloth is cut by the cloth cutting mechanism. It is set to be located.

Next, the CPU 101 waits for input of the press switch 108 (step S8). That is, the determination in step S8 is repeated until the press switch 108 is input, and when there is an input, operation control for operating the press cylinder 72 and lowering the cloth presser is performed (step S9).
Further, the CPU 101 waits for input from the start switch 105 (step S10). That is, the determination in step S10 is repeated until the start switch 110 is input, and when there is an input, the knife operation selection setting set in the setting item 7 of the currently selected pattern data is read and the first knife setting ( It is determined whether or not it is set to execute cloth cutting before sewing (step S11).
In the case of setting the tip knife, the CPU 101 drives the cloth cutting motor 83 to execute the button hole formation by each cloth cutting knife (step S12).

  After the button hole is formed or when it is determined in step S11 that the front knife is not set, the Y-axis motor 74 of the moving mechanism 70 is driven to set the sewing start position on the work cloth on the cloth base 71 to the needle bar 12. Operation control for aligning with the needle entry position is performed (step S13).

Next, the CPU 101 drives the sewing machine motor 3 to execute needle dropping as well as needle swinging, and executes formation of a bouncing seam in accordance with the seam data while achieving synchronization (step S14). At this time, the core yarn is passed through the guide thread 91 of the needle plate through the core thread passage hole 48b of the needle plate through the guide member 91 and the guide tube 92, which are the core thread guide means 90, and reaches the needle hole 48a in advance. It is in a state of being guided between two needle drop points divided into two. Thus, when the formation of the seam is started, the core thread is sewn into the needle swing seam of the upper thread formed by the needle swing.
That is, the X-axis motor 73 and the Y-axis motor 74 are driven to form the core yarn holding section H, and subsequently, the right straight section and the right oblique section are formed in order, The X-axis motor 73, the Y-axis motor 74, and the turning motor 63 are driven to form an arc section, and finally, the X-axis motor 73 and the Y-axis motor 74 are driven to form a left oblique section and a left straight section. Form all the seams of the hole stitches.

Next, the CPU 101 searches for the origin by the origin sensors of the X-axis motor 73 and the Y-axis motor 74 again, and aligns the cloth base 71 of the moving mechanism 70 to the origin position. At the same time, an origin search is performed by the origin sensor of the turning motor 63, and the needle bar and the looper are aligned with a predetermined origin position (step S15).
Further, the CPU 101 again reads out the knife operation selection setting set in the setting item 7 of the currently selected pattern data, and determines whether or not it is the rear knife setting (setting to execute cloth cutting after sewing). (Step S16).
When the rear knife is set, the CPU 101 drives the cloth cutting motor 83 to execute button hole formation with each cloth cutting knife (step S17).
After the formation of the button hole or when it is determined in step S16 that the rear knife is not set, the sewing is completed and the process returns to step S8 to wait for execution of a new hole sewing.

(Effect of embodiment)
In the buttonhole sewing machine 10, the motion control means 100 performs sewing at the sewing start end so that the needle swing width and the sewing pitch of the needle bar 12 are narrower than those of other sewing sections. The core yarn holding section H is formed by controlling the motors 73 and 74. As a result, it is possible to form a needle swing seam having a narrower width and a plurality of needle swing seams formed more densely in the cloth feed direction at the sewing start end, and the sewing start end of the core thread is more It becomes possible to hold firmly and make it difficult to come off. For this reason, even if the core thread and upper thread are slippery materials, or even when the over-width stitching width and sewing pitch of the normal sewing section are wider than the thickness of the core thread, the core thread can be removed. Can be more effectively reduced, and proper buttonhole sewing can be performed.

  Furthermore, the pattern data indicates the position information indicating each needle drop position in the core thread holding section H, “core thread locking stitch length bl”, “number of core thread locking stitches bn”, “core thread locking stitch width correction value” In order to form the core yarn holding section H by including "bw", software processing such as setting and correction of pattern data without changing design or adding a new configuration to each mechanism of the sewing machine. Appropriate buttonhole sewing with reduced withdrawal can be easily realized.

  Further, the buttonhole sewing machine 10 includes an operation panel 104 for setting position information indicating each needle drop position for all sections including the core thread holding section H. The sewing pitch can be arbitrarily set, and an appropriate core thread holding section can be set when various core threads are used or various hole sewing patterns.

(Other)
For the pattern data, the core thread stop stitch length and the number of core thread stop stitches are set as the setting items. Instead, the core thread stop stitch length and the core thread stop stitch pitch (sewing pitch of the core thread retaining section H) are used instead. The set item may be set as a set item, or a combination of the core thread stop stitch pitch and the number of core thread stop stitches may be set as the set item.
The setting item for the core thread stop stitching swing width value is to input a correction value for the needle swing width of the other section, but the needle swing width value itself in the core thread holding section H is input. May be. In that case, it is necessary to set and input the fixed needle swing width in the needle swing mechanism 30 to the operation control means 100 in advance, and the value of the fixed needle swing width and the needle swing width in the core yarn holding section H must be set. The correction operation amount by the X-axis motor 73 in the needle swing is obtained from the value difference.

  Further, the needle swing mechanism 30 may be provided with a drive source (motor) that performs needle swing and a drive source (motor) that adjusts the needle swing width. In this case, the cloth base 71 by the X-axis motor 73 may be provided. It is possible to eliminate the need for operation control for correcting the needle swing width by movement.

  In button hole sewing, sewing that forms a core thread holding section H is additionally performed in front of the sewing start end of normal hole sewing, which has been conventionally performed, but conventional hole sewing is performed. Sewing may be performed so that the core yarn holding section H is included in the section. That is, it is possible to perform sewing with a narrower needle swing width or sewing pitch from the start of sewing to a predetermined number of stitches in the section of the conventional hole sewing.

Further, in the buttonhole sewing machine 10, data specifying the needle drop position for forming the core yarn holding section H is included in the pattern data, and the operation control means 100 controls each part according to the data, thereby the core yarn. Although the holding section H has been formed, it is not necessary to limit to such a method as long as similar sewing can be performed.
For example, the operation control means 100 performs sewing that has a core thread holding section with respect to pattern data for forming each sewing section of a normal hole stitching that has been conventionally performed and does not include the core thread holding section H. It may have a core thread holding section forming section that performs control for conversion and sewing, or may perform control as a core thread holding section forming section.
More specifically, the operation control means 100 determines the needle swing width and the sewing pitch for some sections from the start of sewing to the several stitches in the pattern data or stitch data that do not include the parameters related to the core yarn holding section H. For example, a process of converting the section into a core yarn holding section H may be performed by reducing the ratio or subtracting a predetermined value.
Further, the operation control means 100 reduces the needle swing width or sewing pitch by a predetermined ratio from the needle swing width or sewing pitch in any section of the pattern data or stitch data that does not include the parameter related to the core thread holding section H. Alternatively, a process of adding data of the core yarn holding section H obtained by reduction by subtracting a predetermined value to the pattern data or stitch data may be performed.
Further, in the above embodiment, when the operation control means 100 starts the eyelet stitching, the operation control means 100 changes both the needle swing width of the needle bar 12 and the sewing pitch along the button hole B at the sewing start end. The core thread holding section H is formed to be narrower than the sewing section of the sewing needle, but either one of the needle swing width of the needle bar 12 and the sewing pitch along the button hole B is set to be smaller than that of the other sewing sections. The core yarn holding section H may be formed narrowly.

Further, in the present embodiment, the sewing machine 10 is described by taking as an example an eyelet stitching, but it goes without saying that a core thread holding section may be provided for buttonhole stitching that is not a stitch.
In addition, as shown in FIG. 11, also in the case of performing the hole sewing having the flow tacking section K for performing the flow tacking, the core thread holding section Ha may be provided at the sewing start end portion and the sewing may be performed.

1 is a side sectional view of a buttonhole sewing machine according to an embodiment of the present invention with a part cut away. FIG. 2 is a side view of a buttonhole sewing machine viewed from the opposite side of FIG. 1. It is a top view of the throat plate mounted in the sewing machine. It is a block diagram which shows the control system of a buttonhole sewing machine. FIG. 5 (A) is an explanatory diagram showing various parameters to be set in eyelet stitching, and FIG. 5 (B) is a table listing various parameters excluding the dimensions of the drop-like portion. FIG. 5C is an explanatory diagram showing parameters for determining the size of the drop-like portion, and FIG. 5D is a chart listing combinations of the sizes of the drop-like portions. It is explanatory drawing which shows the data structure of pattern data. It is explanatory drawing which shows the structure of an operation panel. It is explanatory drawing which shows the data structure of stitch data. It is a flowchart which shows the process from the data setting of an eyelet hole sewing machine to the completion of sewing. It is the flowchart which showed the data setting operation | work of an eyelet hole sewing machine in detail. It is explanatory drawing which shows the state which added the core thread holding | maintenance area Ha to the hole stitching which performs a flow tack stop.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Buttonhole sewing machine 11 Sewing needle 12 Needle bar 20 Vertical movement mechanism 30 Needle swing mechanism 40 Looper mechanism 48 Needle plate 70 Movement mechanism 90 Core thread guide means 100 Operation control means 104 Operation panel (position setting means, section setting means)
107 EEPROM
H Core yarn holding section

Claims (5)

A needle bar for holding a sewing needle in which a hole for inserting an upper thread is formed;
A vertical movement mechanism for moving the needle bar up and down;
A needle swinging mechanism that swings the needle bar in a direction intersecting the longitudinal direction of the button hole formed in the work cloth;
A looper mechanism that forms a seam on the work cloth in cooperation with the needle bar;
A moving mechanism for moving the work cloth in a direction perpendicular to the vertical direction of the sewing needle;
A core yarn guide means for guiding an end portion of the core yarn supplied from the core yarn supply source between needle swing seams formed by needle swing of the needle swing mechanism;
Storage means for storing sewing data for forming buttonhole stitches having at least left and right side stitches around the buttonhole;
Control means for controlling the respective mechanisms based on the sewing data to form a looped seam around the button hole;
Buttonhole sewing machine with
The control means includes a core thread holding section at the sewing start end portion for performing sewing by narrowing at least one of the needle swing width of the needle bar or the sewing pitch along the button hole as compared with other sewing sections. A buttonhole sewing machine characterized by controlling the forming.   The sewing data includes position information indicating each needle drop position of the core thread holding section, and the control means forms a seam of the core thread holding section according to the sewing data. The buttonhole sewing machine according to 1.   3. The buttonhole sewing machine according to claim 2, further comprising position setting means for setting position information indicating each needle drop position in the core yarn holding section.   The control means performs control for performing sewing by converting the sewing data not including position information indicating each needle drop position in the core thread holding section into sewing having the core thread holding section. 2. The buttonhole sewing machine according to claim 1, wherein   The buttonhole sewing machine according to any one of claims 1 to 4, further comprising section setting means for setting the number of needles or section length of the core yarn holding section.

Images