JP4686025B2 - Sewing machine thread trimmer - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a thread trimming device for a boring machine for automatically performing boring sewing such as button holes.
[0002]
[Prior art]
For example, a perforated hole sewing machine that applies a seam stitch around the eyelet hole to the sewing product generally has the following configuration.
In other words, the presser foot device is attached to a feed stand provided on the bed portion of the sewing machine, and the workpiece is held on the feed stand by the presser foot device. The feed table is fed with a feed drive along the cut-out shape of the eyelet hole by the feed device.
Further, the needle bar provided on the arm portion of the sewing machine is moved up and down by a needle bar up-and-down driving mechanism, and the sewing needle is swung from side to side by the needle swinging mechanism provided in the arm portion.
Along with the vertical movement and needle swing of the needle bar, the looper driving mechanism provided in the bed unit operates the looper, and over stitching is performed along the eyelet hole by the cooperation of both.
In addition, the cloth cutting device which consists of a knife and a hammer is provided, and an eyelet hole is cut into a to-be-sewn material at a desired timing.
[0003]
In such an eyelet sewing machine, a core thread guide mechanism is provided in the vicinity of the looper, and the core thread drawn from the supply source is led out between the left and right needle swing positions so that the core thread is within the seam. It is designed to reinforce the seam. In addition, the sewing machine feed base is provided with a thread trimming device that cuts the lower thread and the core thread after the overlock stitching is completed.
[0004]
Hereinafter, a conventional thread trimming device and mechanisms disposed in the vicinity thereof will be described with reference to the drawings.
As shown in FIG. 16, a left presser vertical movement mechanism 504 that moves the left presser 506 up and down is provided at the rear end of the left feed base 502. Further, a left receiving plate 508 that supports the sewing product at the lower part of the sewing product is provided at the right end of the left feed base 502. Then, the left presser 506 is lowered, and the left presser 506 and the left receiving plate 508 hold the workpiece to be sewn on the left side of the eyelet hole.
Left and right feed bases 501 and 502 are arranged facing left and right. A right presser vertical movement mechanism 503 that moves the right presser 505 up and down is provided at the rear end of the right feed base 501. Further, a right support plate 507 that supports the sewing product at the lower part of the sewing product is provided at the left end of the right feed base 501, and the right presser 505 is lowered so that the right presser 505 and the right support plate 507 The workpiece to be sewn in the vicinity of the right side of the eyelet hole is clamped. In addition, between the right receiving plate 507 and the left receiving plate 508, hole sewing is performed on the clamped workpiece, and the eyelet hole is cut.
[0005]
The thread trimming device includes an upper knife 509, a lower knife 510, a cam plate 512 that operates the upper knife 509 and the lower knife 510, and a link mechanism 513 that transmits the power of the driving means 514 to the cam plate 512. Has been.
The upper and lower knives 509 and 510 are supported by the right feed base 501 so that their intermediate portions can be rotated by step screws 511, the upper knife 509 is positioned above the lower knife 510, and the lower knife 510 is received by the right from the upper knife 509. It is arranged in front of the plate 507.
The tip of the lower knife 510 is positioned at the lower part of the sewing product, and the sewing product is clamped by the right presser 505 on the right side of the eyelet hole. In addition, a cam contact portion 510 b is formed at the base end portion of the lower knife 510, and the cam contact portion 510 b comes into contact with the cam surface 512 a of the cam plate 512. The cam plate 512 is rotatably supported on the right feed base 501 by a step screw 515.
[0006]
Further, a cam contact portion 509b is formed at the base end portion of the upper knife 509 whose side edge is the blade 509a, and the cam portion 512b of the cam plate 512 is configured to contact the cam contact portion 509b. ing.
[0007]
When the blade 509a of the upper knife 509 and the blade 510a of the lower knife 510 are opened, the cam plate 512 is fitted between the cam contact portion 509b of the upper knife 509 and the cam contact portion 510b of the lower knife 510. ing. At this time, the lower thread and the core thread facing the looper and the core thread guide mechanism are sandwiched at the end of the seam formed along the eyelet hole in the sewing product, and the blades of the upper knife 509 are disposed on both sides thereof. 509a and the blade 510a of the lower knife 510 are arranged.
[0008]
When the link mechanism 513 is actuated by the driving means 514 and the cam plate 512 is rotated, the cam contact portion 509b of the upper knife 509 and the cam contact portion 510b of the lower knife 510 are expanded, and the upper knife 509 and the lower knife 509 are pushed downward. The knife 510 is rotated around the step screw 511. As a result, the blade 509a of the upper knife 509 and the blade 510a of the lower knife 510 are engaged in the vicinity of the end of the seam, and the lower thread and the core thread are cut. By cutting in this way, it is possible to cut the lower thread and the core thread by shortening the length (remaining thread) from the end of the seam to the lower thread cutting part and the core thread cutting part.
[0009]
[Problems to be solved by the invention]
By the way, the eyelet stitching is composed of the eyelet part and the left and right straight parts connected to the eyelet part, but the length of the straight part may be changed depending on the length of the straight part of the eyelet hole. The front and back positions of the seam end are different. That is, the end position of the seam is rearward (upward in FIG. 16) as the length of the straight part of the eyelet hole is shortened, and the end position of the seam is forward (downward in FIG. 16) as the length of the straight part of the eyelet hole is increased. )become.
Therefore, in order to cut so that the remaining thread is shortened when the length of the straight portion of the eyelet hole changes, the blade 509a and the lower knife 509a of the upper knife 509 are arranged near the end in accordance with the position of the end of the seam. It is necessary to engage the blade 510a of the knife 510.
[0010]
Since the lower knife 510 in the conventional thread trimming device is arranged along the straight part side of the eyelet when the upper and lower knifes are expanded, by making the blade 510a of the lower knife 510 longer along the straight part, Even if the length of the straight portion changes, it can be positioned near the end of sewing.
However, as shown in FIG. 16, the upper knife 509 has a stepped screw on the right receiving plate 507 from the expanded position positioned on the extended line of the straight part of the eyelet hole to the cutting position engaged with the lower knife 510. Since the upper knife 509 is lengthened, the distal end of the upper knife 509 is engaged with the front end of the left receiving plate 508 because the upper knife 509 is lengthened.
That is, it is very difficult to widen the front-rear range in which the blade 509a of the upper knife 509 and the blade 510a of the lower knife 510 can be engaged with each other, and the corresponding length of the eyelet hole that can be cut by the conventional thread trimmer is very large. The range was narrow.
[0011]
Accordingly, an object of the present invention is to solve the above-mentioned problems, widen the front and rear range in which the thread can be cut, and cut the thread by shortening the remaining thread according to the position of the end of the seam. It is to provide a thread trimming device.
[0012]
[Means for Solving the Problems]
In order to solve the above problems, the invention described in claim 1
A thread of a sewing machine having an upper knife and a lower knife for cutting the thread forming the stitch from the left and right at the sewing end position, and wherein the sewing end position of the thread to be cut can be displaced over a predetermined range in a straight line direction In the cutting device,
A lower knife which is supported so as to be able to rotate in a direction close to the upper knife across a sewing thread with respect to one fixed axis, and which can face the entire displacement range of the sewing end position;
An upper knife which is supported so as to be rotatable in a direction approaching a lower knife with a sewing thread interposed while moving along the straight line direction, and the movement along the straight line direction corresponds to a displacement range of the sewing end position; Prepared.
[0013]
Thereby, the thread trimming device can be made compact and the thread trimming range can be expanded.
[0014]
The invention according to claim 2
A thread of a sewing machine having an upper knife and a lower knife for cutting the thread forming the stitch from the left and right at the sewing end position, and wherein the sewing end position of the thread to be cut can be displaced over a predetermined range in a straight line direction In the cutting device,
A lower knife which is supported so as to be able to rotate in a direction close to the upper knife across a sewing thread with respect to one fixed axis, and which can face the entire displacement range of the sewing end position;
And an upper knife which is supported so as to be rotatable in a direction close to the lower knife with the sewing thread interposed therebetween while moving along the straight line direction, and capable of adjusting a moving range along the straight line direction.
[0015]
Thereby, similarly to claim 1, the thread trimming device can be made compact and the thread trimming range can be expanded.
[0016]
The invention according to claim 3
A presser (for example, the left and right pressers 112) that presses the vicinity of the sewing position of the sewing product,
It has a receiving part (for example, the left receiving plate 113, the right receiving plate 213) which puts the sewing product between the presser and moves the sewing product in the sewing direction by placing the sewing product. A feeding base
A thread trimming device (37) having an upper knife (301) and a lower knife (302) provided on the feed base side and cutting the thread extending from the sewing end position in the vicinity of the sewing end position after the end of the hole sewing. ), And a thread trimming device (37) for a sewing machine comprising:
When moving the blade of the upper knife and the blade of the lower knife from the open state to the position where the upper knife is vertically overlapped and closed at the cutting position of the thread, the sewing machine passes the needle position in the locus drawn by the tip of the upper knife. In the axial direction of Along Direction travel distance D1 and the axial direction Orthogonal The ratio D1 / D2 with the moving distance D2 in the direction is
A knife moving means for moving the upper knife so that the trajectory drawn by the tip of the upper knife becomes larger by rotating the upper knife about the rotation fulcrum of the lower knife as compared to a case where the locus drawn by the arc is an arc. For example, guide grooves 340, 341, step screws 316, and support shafts 318) are provided.
[0017]
In this case, the axial direction of the sewing machine means the front-rear direction in which the sewing machine arm portion extends.
The moving distance of the sewing machine in the axial direction (front-rear direction of the sewing machine) passing through the needle position in the locus drawn by the upper knife tip is D1, and in this axial direction Orthogonal The moving distance in the direction is D2, and the ratio of the moving distance D1 and the moving distance D2 is D1 / D2.
Then, by rotating the upper knife about the rotation fulcrum of the lower knife, the ratio D1 / D2 becomes larger than when the locus drawn by the tip of the upper knife is an arc, and the knife moving means is moved upward. The knife is moved.
The lower knife may be rotated by a knife moving means, or the lower knife may be rotated by another moving means.
[0018]
Since the upper knife moves as described above, for example, when the upper knife blade and the lower knife blade are closed than when the upper knife rotates around the same fulcrum as the pivot of the lower knife. The tip of the upper knife is located further rearward from the position corresponding to, for example, the front and rear of the front end of the left receiving portion.
That is, when the upper knife moves to the cutting position so that the tip of the upper knife does not contact the left receiving portion, the movement distance D1 is larger than the movement distance D2, and therefore the upper knife is centered on the same fulcrum as the rotation fulcrum of the lower knife. Thus, the position of the tip of the upper knife is rearward than when the left backing plate is rotated.
[0019]
Therefore, for example, an upper knife blade longer than the conventional example can be used. Thereby, the range before and behind which can be cut | disconnected with the blade of an upper knife and the blade of a lower knife becomes wide. Then, the thread can be cut by shortening the remaining thread corresponding to the longer sewing length.
In the above description, the arrangement of the upper knife and the lower knife is the right feed base, but the left and right arrangement relationship of the upper knife and the lower knife may be reversed. Further, the range before and after cutting with the blade of the upper knife and the blade of the lower knife is the front and rear distance from the front end of the left receiving plate to the tip of the upper knife when the upper knife and the lower knife are closed to each other.
[0020]
According to a fourth aspect of the present invention, in the yarn cutting device according to the third aspect,
The receiving portion is provided in a state of being divided into left and right receiving plates (for example, a left receiving plate 113 and a right receiving plate 213) with a sewing machine axis passing through the needle position as a boundary,
With the upper knife and the lower knife open, the lower knife moves the blade of the lower knife near the axis on the front side of one of the left and right receiving plates of the receiving portion. Arranged so as to be substantially along the axis, and the upper knife is arranged so as to extend from the front of one backing plate to the front of the other backing plate,
At the time of cutting the thread, the knife moving means rotates the lower knife so that the blade approaches the axis, and the upper knife moves the blade closer to the axis, and the other of the receiving portions. The tip extending toward the receiving plate is moved along the locus so as to avoid the other receiving plate.
[0021]
According to the fourth aspect of the invention, when the upper knife and the lower knife move from the open state to the closed state, the tip of the upper knife moves along the locus from the front of the other receiving plate. In order to move away from the other receiving plate, the upper knife moves to the cutting position.
At this time, since the tip of the upper knife draws the locus, for example, as in the invention according to claim 3, for example, the upper knife moves above and moves around the same fulcrum as the rotation fulcrum of the lower knife. When the blade of the knife and the blade of the lower knife are closed, the tip of the upper knife is positioned further rearward from the position corresponding to the front and rear of the front end of the other receiving plate. Therefore, the front / rear range in which the thread can be cut with the blade of the upper knife and the blade of the lower knife is expanded, and the thread is cut in the vicinity of the sewing end in accordance with the length of the parallel part of the button hole. Can do.
Further, since the lower knife is also rotated by the knife moving means, it is not necessary to provide another rotating means for rotating the lower knife, and the thread trimming device can be provided with a simple structure.
[0022]
The invention according to claim 5 is the thread trimming device according to claim 3 or 4,
The upper knife is provided with guide grooves (340, 341) having longitudinal directions in two different directions, and two guide grooves inserted into the two guide grooves at the attachment position of the upper knife of the feed base, respectively. Fulcrum shafts (for example, stepped screws 316, support shafts 318) are provided, and two guide grooves into which the fulcrum shafts are inserted move along the locus along the locus when the yarn is cut. It is characterized by having a shape that guides to.
[0023]
The invention according to claim 5 is a desirable specific configuration of the yarn cutting device according to claim 3 or 4. According to the third aspect of the invention, since the upper knife is provided with a guide groove shaped to guide the tip of the upper knife along the locus, the structure of the thread trimming device is simplified. Further, since the upper knife is moved along the locus only with two guide grooves and two support shafts, the structure of the thread trimming device is simplified.
[0024]
In addition, since the tip of the upper knife draws the locus as in the third aspect of the invention, for example, the upper knife moves more about the same fulcrum as the rotation fulcrum of the lower knife. When the blade and the blade of the lower knife are closed, the tip of the upper knife is positioned further rearward from the position corresponding to the front and rear of the front end of the other receiving plate. Therefore, the front / rear range in which the thread can be cut with the blade of the upper knife and the blade of the lower knife is expanded, and the thread is cut in the vicinity of the sewing end in accordance with the length of the parallel part of the button hole. Can do.
[0025]
A sixth aspect of the present invention is the yarn cutting device according to the fifth aspect,
One fulcrum shaft (for example, a step screw 316) of the two fulcrum shafts also serves as a fulcrum for the rotational movement of the lower knife.
[0026]
According to the sixth aspect of the present invention, the upper knife and the lower knife are substantially scissors, and in order to reliably cut the thread between the upper knife and the lower knife, the upper knife and the lower knife However, since the pivot point of the lower knife also serves as one of the two fulcrum shafts, the adjustment of the knife pressure is simplified. In addition, when the upper knife blade and the lower knife blade are closed, for example, as in the case of the first aspect of the invention, for example, when the upper knife rotates around the same fulcrum as the lower fulcrum. Further, the tip of the upper knife is located further rearward from the position corresponding to the front and rear positions of the front end of the other receiving plate. Therefore, the front / rear range in which the thread can be cut with the blade of the upper knife and the blade of the lower knife is expanded, and the thread is cut in the vicinity of the sewing end in accordance with the length of the parallel part of the button hole. Can do.
[0027]
The invention according to claim 7 is provided on the feed base side under the sewing product of a buttonhole sewing machine having a feed base on which the sewing product is placed and the sewing product is moved in the sewing direction. A thread trimming device comprising an upper knife and a lower knife for cutting a thread extending from the sewing end position of the sewing of the workpiece after the end of the hole sewing, in the vicinity of the sewing end position;
A female fulcrum member (for example, a female attachment 303) having an operation fulcrum between the upper knife and the lower knife, and the female fulcrum member attached to the feed base and attaching the female fulcrum member A fixed base portion (for example, the right feed plate 201) whose position can be changed along the axial direction of the sewing machine is provided.
As described above, according to the seventh aspect of the invention, since the attachment position of the female fulcrum member can be changed along the sewing machine shaft direction with respect to the fixed base provided on the feed base, the sewing end position (sewing) The cutting range that can be cut by the blade of the upper knife and the blade of the lower knife can be changed along the sewing machine axis in accordance with the length). In addition, when changing the mounting position of the upper knife and lower knife, the upper knife and lower knife remain in the shape of scissors and change in the axial direction of the sewing machine together with the knife fulcrum member. No need to readjust.
[0028]
The invention according to claim 8 is the yarn cutting device according to claim 7,
When cutting the thread, the upper knife blade and the lower knife blade are moved from a mutually open state to a position where they are overlapped and closed at the thread cutting position (for example, a driving mechanism 31). ), An upper knife link (304) rotatably connected to the upper knife, a lower knife link (305) rotatably connected to the lower knife, and the upper source link A connecting link (306) connected to the female link and the lower female link and transmitting a driving force to the upper female link and the lower female link and operating substantially linearly during transmission; The connection position of at least one of the connection portion between the link and the lower female link and the connection portion with the drive source can be changed substantially along the axial direction of the sewing machine. Is shall.
As described above, according to the eighth aspect of the present invention, the connection position of at least one of the connecting portions with the upper female link and the lower female link and the connecting portion with the drive source is in the axial direction of the sewing machine. The position of the upper knife and the lower knife along the upper knife link and the lower knife link along the axial direction of the sewing machine with the upper knife link and the lower knife link can be changed. Can be changed.
That is, the positions of the upper knife and the lower knife can be changed along the axial direction of the sewing machine while being scissors-like. Accordingly, the same function and effect as those of the invention of claim 7 can be obtained, and the cutting range of the upper knife and the lower knife can be changed along the sewing machine shaft in accordance with the sewing end position, and the upper knife and the lower knife can be changed. No need to adjust the knife pressure.
[0029]
The invention according to claim 9 is the yarn cutting device according to claim 8,
One of the fixed base portion and the female fulcrum member has a plurality of first engaging portions (for example, mounting holes 322, 322,...) For positioning the other along the axial direction of the sewing machine. The second engaging portion (for example, the engaging portion 303b) that engages with the first engaging portion is provided on the other side, and the connection link includes the upper female link and the upper female link. At least one of the connecting portions to the lower female link and the connecting portion to the drive source (for example, the attaching portions 306a, 306a,...) Corresponds to the plurality of first engaging portions. A plurality of the sewing machines are arranged along the axis of the sewing machine.
[0030]
As described above, according to the ninth aspect of the invention, the position of the female fulcrum member in the axial direction of the female fulcrum member relative to the fixed base is obtained by engaging the second engaging portion with the plurality of first engaging portions. Can be changed. Accordingly, the position of the upper knife and the lower knife in the axial direction of the sewing machine can be changed in the form of scissors, so that the cutting range of the upper knife and the lower knife can be changed along the axis of the sewing machine in accordance with the sewing end position. Adjustment of the knife pressure between the upper knife and the lower knife becomes unnecessary.
Further, the connecting link includes at least one of a connecting portion with the upper female link and the lower female link and a connecting portion with the driving source, and a plurality of first engaging portions along the axial direction of the sewing machine. Therefore, it is not necessary to change the arrangement position of the drive source along the axial direction of the sewing machine.
The positions of the upper knife and the lower knife can be changed along the axial direction of the sewing machine with a simple configuration of the first engagement portion, the second engagement portion, and the connection portion, and the drive source There is no need to change the arrangement position along the axis of the sewing machine.
[0031]
A tenth aspect of the present invention is the yarn cutting device according to any one of the seventh, eighth, and ninth aspects,
In a state where it is arranged at the standby position before cutting, the side edge serving as the blade of the lower knife is arranged in a direction substantially along the axis of the sewing machine, and the side opposite to the side edge serving as the blade of the lower knife An edge (302c) is formed so as to be parallel to a side edge serving as a blade, and the lower knife is stopped so as not to move to the right of the standby position, and a stopper (movable in a direction crossing the axis of the sewing machine) For example, a stopper screw 326) is provided.
[0032]
As described above, according to the tenth aspect of the present invention, the stopper that stops the lower knife from moving to the right of the standby position is movable in the direction intersecting the axis of the sewing machine. Can be adjusted. In addition, since the side edge that becomes the blade of the lower knife and the side edge opposite to the side edge are parallel, the position of the lower knife is adjusted in advance, and then the upper knife and the lower knife are There is no need to adjust the position of the lower knife when the front / rear position is changed.
[0033]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of a thread trimming device for a sewing machine according to the present invention will be described below with reference to FIGS.
In FIG. 1, an eyelet sewing machine 1 includes a sewing machine frame 10 and has the following configuration. That is, the sewing machine frame 10 includes a bed portion 11 having a substantially rectangular box shape, a vertical trunk portion 20 standing at the rear portion of the bed portion 11, and an upper portion of the vertical trunk portion 20 so as to be substantially parallel to the bed portion 11. And an arm portion 12 extending forward, and is placed on a sewing machine table (not shown) via a bottom cover 13. In the following description, the axial direction of the sewing machine means the front-rear direction.
A needle bar 15 having a sewing needle 14 at the lower end is disposed on the head (front end) of the arm 12 so as to be movable up and down and to be able to swing left and right for each stitch.
[0034]
The bed portion 11 is provided with two loopers (not shown) located immediately below the needle bar 15. These loopers operate in synchronism with the vertical movement and needle swinging movement of the needle bar 15, thereby forming a seam on the workpiece to be laid on the feed base 16 in cooperation with the sewing needle 14. A core yarn guide mechanism (not shown) is disposed in the vicinity of the looper. The core thread guide mechanism is for guiding the core thread 52 (shown in FIG. 5 and the like) drawn from the thread supply source between the left and right needle swing positions of the sewing needle 14, and the core thread 52 is placed in the seam. It is configured to reinforce the seam by sewing.
Further, a cloth cutting knife 17 (shown in FIG. 4 and the like) positioned on the depth side (rear side) of the looper is brought into contact with and separated from the bed cutting knife 17 from above the cloth cutting knife 17. A cloth cutting device 19 (shown in FIG. 4 and the like) provided with a hammer 18 is disposed, and the cloth cutting device 19 is operated at a required timing, whereby a workpiece includes a round hole portion and a straight portion. The eyelet can be cut.
[0035]
On the upper surface of the bed portion 11, a feed base 16 on which a workpiece is placed is disposed. A left feed plate 101 and a right feed plate 201 constituting the upper surface of the feed table 16 are provided on the feed table 16. The left feed plate 101 and the right feed plate 201 are opposed to each other on the left and right, with the axis of the sewing machine extending in the front-rear direction (the front-rear direction line passing through the vertical trajectory of the sewing needle 14) as the center. The left feed plate 101 and the right feed plate 201 are respectively provided with a left-hand presser device 102 and a right-hand presser device 202 (shown in FIG. 2 and the like), which will be described later. To hold the workpiece on both sides of the notch (eyelet hole).
The feed base 16 has a thin rectangular box as a whole, and is driven by a feed device including two pulse motors (not shown) so as to be movable in the left-right direction and the front-rear direction. The feed base 16 is moved to the sewing start position ahead of the origin position by the operation of a start switch (not shown) while being positioned at the origin position, and is moved along the eyelet hole to be formed on the sewing product. Is set. As a result, the workpiece placed on the feed base 16 can be moved to a required position directly below the sewing needle 14 and the stitches can be sequentially stitched along the eyelet holes.
Then, after the hole stitching is formed on the sewing product along the eyelet hole, the feed base 16 returns to the origin position, and above and below the eyelet hole sewing position on the sewing product placed on the upper surface thereof, The cloth cutting knife 17 and the hammer 18 are set to face each other. At this position (cloth cutting position), the hammer 18 descends to form a cut along the eyelet hole.
[0036]
Further, a thread trimming device 27 is provided on the right feed plate 201 of the feed base 16. The thread trimming device 27 has a lower thread 51 (illustrated in FIG. 5 or the like) extending from the end of the seam formed along the eyelet hole of the sewing product to the needle plate 21 (illustrated in FIG. 4 or the like) after the overlock stitching is finished. ) And a core thread 52 (shown in FIG. 5 and the like) extending from the end of the seam to the core thread guide mechanism.
[0037]
Details will be described with reference to the drawings.
First, the left and right left presser devices 102 and 202 will be described. In FIG. 2, a presser arm mounting base 103 is attached to the upper surface of the rear end portion of the left feed plate 101 with a screw 104. A fulcrum shaft 105 extending to the left and right is attached to the presser arm mounting base 103 so as to be rotatable by C-rings 106 and 106. The fulcrum shaft 105 is inserted into the presser arm base 107 and fixedly fastened by a screw 108. A rear end portion of the presser arm 109 extending in the front-rear direction is held by the presser arm base 107 and fixedly fastened by a screw 110. A presser 112 is swingably attached to the front end portion of the presser arm 109 by a step screw 111. In the left cloth presser device 102, when the presser arm base 107 is rotated, the presser arm 109 is raised and lowered, and the presser 112 is moved up and down. In the presser arm base 107, an urging means (not shown) urges the presser 112 downward, and a driving means (not shown) moves the presser 112 upward.
[0038]
The right presser device 202 is provided at the rear end portion of the right feed plate 201 and is opposed to the left presser device 102 around the axis of the sewing machine. The configuration of the right presser device 202 is the same as that of the left presser device 102, and the same configuration as the left presser device 102 is denoted by the same reference numeral, and the description thereof is omitted.
[0039]
On the other hand, a left receiving plate 113 is attached to the right edge of the upper surface of the left feed plate 101 with screws 114. The left receiving plate 113 has a longitudinal direction in the axial direction of the sewing machine. Then, when the left presser 112 is lowered, the workpiece is held between the left presser 112 and the left receiving plate 113. A right receiving plate 213 is attached to the left edge of the upper surface of the right feed plate 201 with screws 214. The right receiving plate 213 is disposed opposite to the left receiving plate 113. Then, when the right presser 112 is lowered, the workpiece is held between the right presser 112 and the right receiving plate 213. In this manner, the left side of the eyelet to be sewn is pressed by the left presser 112 and the left receiving plate 113, and the right side of the eyelet to be sewn is pressed by the right presser 112 and the right receiving plate 213.
[0040]
Next, the thread trimming device 37 will be described with reference to FIGS.
This thread trimming device 37 includes a thread trimming body 30 that cuts the lower thread 51 and the core thread 52 extending from the end of the eyelet stitching, a drive mechanism 31 that drives the thread trimming body 30, and a right feed plate 201. And is composed mainly.
[0041]
First, the drive mechanism 31 will be described.
[0042]
As shown in FIG. 3, the bracket 308 is attached to the inside of the front end portion of the feed base 16 by screws 309, and the cylinder 307 is fixed to the inside of the feed base 16 by the bracket 308. The cylinder 307 is disposed below the left feed plate 101 and the right feed plate 201. A pawl 310 is attached to the drive output which is the tip of the cylinder 307. A roller 311 a is attached to one end of the thread trimming link arm 311, and the roller 311 a is engaged with the pawl 310. A shaft portion 312 a is formed at one end of the thread trimming drive arm 312, and the shaft portion 312 a is rotatably inserted into the hole of the right feed plate 201. The shaft portion 312 a is held on the other end of the thread trimming link arm 311, and the shaft portion 312 a is fixedly connected to the thread trimming link arm 311 by a screw 313. An end portion different from the end portion where the shaft portion 312a of the thread trimming drive arm 312 is formed serves as a connecting portion with the thread trimming body 30 described later. A spring 328 is attached to the thread trimming link arm 311 so as to urge the upper knife 301 and the lower knife 302, which will be described later, to open.
[0043]
Next, the thread trimming body 30 will be described.
[0044]
The thread trimming body 30 includes a scissors-like upper knife 301 and lower knife 302 that cut the lower thread 51 and the core thread 52 extending from the end of the eyelet stitching in the vicinity of the end of the stitch, and the upper knife 301. A female attachment portion 303 to which the lower knife 302 is attached, an upper knife link 304 rotatably connected to the upper knife 301, a lower knife link 305 rotatably connected to the lower knife 302, an upper knife link 304, and The connecting link 306 connected to the lower female link 305 is mainly configured.
[0045]
At the front portion of the connecting link 306 having a longitudinal direction in the axial direction of the sewing machine, attachment portions 306a, 306a,... Arranged in the axial direction of the sewing machine at predetermined intervals are formed. A protruding portion 306 b is formed at the rear end portion of the connecting link 306. Further, one end portion of the upper female link 304 and one end portion of the lower female link 305 are rotatably attached to a substantially middle portion of the connecting link 306 by a step screw 314. A base end portion of the upper knife 301 is rotatably connected to the other end portion of the upper knife link 304. A base end portion of the lower knife 302 is rotatably connected to the other end portion of the lower knife link 305.
[0046]
An engaging portion 303 b is formed on the lower surface of the female attachment portion 303, and a concave portion 303 a is formed on the upper surface of the female attachment portion 303. A leaf spring washer 315 is fitted into the recess 303a. A lower knife 302 is attached to the upper surface of the knife attachment portion 303 by a step screw 316 so as to be rotatable. A step screw 316 is inserted into the leaf spring washer 315. A blade 302 b is formed on the left edge of the lower knife 302.
[0047]
The upper knife 301 is provided on the upper surface of the lower knife 302. The upper knife 301 is provided with guide grooves 340 and 341 having longitudinal directions in different directions. A support shaft 318 provided in the female attachment portion 303 is slidably inserted into one guide groove 340. The step screw 316 is slidably inserted into the other guide groove 341, and the upper knife 301 is attached to the knife attachment portion 303 by this step screw 316. A blade 301 c is formed on the right edge of the tip of the upper knife 301. Further, on the upper surface of the upper knife 301, a cloth thread 319 is attached in the vicinity of the blade 301c with a screw 320.
[0048]
As described above, the thread trimming body 30 includes the upper knife 301, the lower knife 302, the knife mounting portion 303, the upper knife link 304, the lower knife link 305, and the connecting link 306 that are integrated.
[0049]
Next, adjustment of the knife pressure of the upper knife 301 and the lower knife 302 will be described.
As shown in FIG. 6, when an operator or the like tightens the step screw 316, the leaf spring washer 315 is compressed and pressure is applied to the upper knife 301 and the lower knife 302. That is, the operator can adjust the knife pressure of the upper knife 301 and the lower knife 302 by adjusting the tightening of the step screw 316.
[0050]
Next, attachment of the thread trimming body 30 to the right feed plate 201 will be described.
3 and 4, a groove 201a having a longitudinal direction in the axial direction of the sewing machine is formed in the right feed plate 201, and an insertion hole 201b having a longitudinal direction in the axial direction of the sewing machine is formed in the groove 201a. Is formed. The right feed plate 201 is provided with mounting holes 322, 322,... Arranged in the axial direction of the sewing machine at a predetermined interval. The right feed plate 201 is provided with a stopper screw 326 slidable in a direction substantially perpendicular to the axial direction of the sewing machine. The stopper screw 326 is fixed at a predetermined position on the right feed plate 201 by being screwed and tightened to the screw fixing member 327.
[0051]
An operator or the like fits the connecting link 306 into the groove 201 a, so that the thread trimming main body 30 is attached to the right feed plate 201. That is, when the connecting link 306 is fitted in the groove 201a so as to be slidable in the axial direction of the sewing machine, the protrusion 306b of the connecting link 306 is inserted into the insertion hole 201b so as to be slidable in the axial direction of the sewing machine. . In addition, when the engagement portion 303b of the female attachment portion 303 is inserted into any one of the attachment holes 322, 322,..., The engagement portion 303b engages with the attachment hole 322. Then, an operator or the like fixes the female attachment portion 303 to the right feed plate 201 with screws 325 and 325. Then, an operator or the like attaches an end 312b opposite to the end provided with the shaft 312a of the thread trimming drive arm 312 with a step screw 329 corresponding to the attachment hole 322 into which the engaging portion 303b is inserted. .. Are attached to any one of the attachment portions 306a of the portions 306a, 306a,. In this way, the front and rear positioning of the knife attachment portion 303 with respect to the right feed plate 201 is performed.
[0052]
An operator or the like covers the thread trimming body 30 with the knife cover 321 in a state where the thread trimming body 30 is attached to the right feed plate 201. Thereby, when the thread trimming device 37 is operated, the sewing product is prevented from being caught in the thread trimming device 37.
[0053]
As described above, FIG. 4 shows a state in which the blade 301c of the upper knife 301 and the blade 302b of the lower knife 302 are opened to each other with the thread trimming body 30 attached to the right feed plate 201.
As shown in FIG. 4, in the state where the lower knife 302 is disposed at the standby position before the lower thread 51 and the core thread 52 are cut, the side edge serving as the blade 302b of the lower knife 302 is substantially along the axial direction of the sewing machine. Arranged in the direction. Further, the blade 302b faces the left receiving plate 113. And the side edge 302c on the opposite side to the blade 302b is arrange | positioned substantially in parallel with the side edge used as the blade 302b. When the stopper screw 326 is tightened, the stopper screw 326 is fixed, and the lower knife 302 is positioned in a state where the upper knife 301 and the lower knife 302 are opened to each other. More specifically, as shown in FIG. 7, the side edge that becomes the blade 302 b of the lower knife 302 is opposite to the side edge that becomes the blade 302 b of the lower knife 302 so that the side edge becomes continuous with the left edge of the right backing plate 213. The stopper screw 326 contacts the side edge 302c on the side.
[0054]
Referring to FIG. 4, in this open state, the side edge that is the tip of lower knife 302 is disposed adjacent to the front end of right receiving plate 213. And the side edge used as the front-end | tip of the lower knife 302 is arrange | positioned in the back side rather than the front end of the said left receiving plate 113. FIG. Further, the thickness of the lower knife 302 is substantially equal to the thickness of the right backing plate 213, and the right presser 112 is lowered so that the sewing product is clamped by the right presser 112 and the lower knife 302. It has become. As a result, the right side of the eyelet to be sewn is pressed.
[0055]
As described above, by arranging the side edge to be the blade 302b of the lower knife 302 continuously with the left edge of the right backing plate 213, the lower knife 302 and the right presser 112 securely hold the workpiece. be able to. Therefore, the occurrence of sewing defects such as stitch skipping during sewing is prevented.
[0056]
In a state where the upper knife 301 is disposed at the standby position before cutting, the upper knife 301 is disposed so as to extend from the front of the right receiving plate 213 to the front of the left receiving plate 113. In this state, the blade 301c of the upper knife 301 faces the eyelet hole to be sewn. The spring 328 urges the connecting link 306 forward via the thread trimmer link arm 311 and the thread trimmer drive arm 312 so that the upper knife 301 and the lower knife 302 are opened to each other as described above. In the standby position before cutting.
[0057]
FIG. 5 shows a closed state in which the blade 301c of the upper knife 301 and the blade 302b of the lower knife 302 overlap each other at the cutting position.
When the blade 301c of the upper knife 301 and the blade 302b of the lower knife 302 are opened from each other, the connecting link 306 slides backward against the biasing force of the spring 328, so that the lower knife link 305 is connected to the connecting link 306. It rotates around the front end. As a result, the lower knife 302 rotates around the step screw 316, and the blade 302b of the lower knife 302 moves to the left toward the cutting position.
Similarly, when the connecting link 306 slides backward, the upper female link 304 rotates about the tip of the connecting link 306. Thereby, since the upper knife link 304 is rotatably connected to the base end portion of the upper knife 301, the upper knife 301 is moved. As a result, the stepped screw 316 inserted in the guide groove 341 slides along the guide groove 341 relative to the upper knife 301. Further, the support shaft 318 inserted into the guide groove 340 moves relative to the upper knife 301. Since the step screw 316 and the support shaft 318 are fixed to the knife mounting portion 303, the tip of the upper knife 301 draws a predetermined locus L so that the blade 301c of the upper knife 301 moves to the cutting position. It has become.
[0058]
The locus L will be described with reference to FIG.
As shown in FIG. 8, with the blade 301c of the upper knife 301 and the blade 302b of the lower knife 302 opened, the position of the tip of the upper knife 301 when the upper knife 301 is in the standby position is defined as position O. An arbitrary point on the locus L is set as a point P. A distance in the axial direction of the sewing machine from the position O to the point P is defined as a distance D1 (movement distance D1), and a distance from the position O to the point P in a direction substantially orthogonal to the axis of the sewing machine is a distance D2 (movement distance D2). And A ratio between the distance D1 and the distance D2 is set as a ratio D1 / D2. At this time, the relationship between D1 and D2 is D1> D2. The axial direction of the sewing machine when the upper knife 509 rotates and moves around the rotation fulcrum (that is, the step screw 511) of the lower knife 510 as in the conventional example, and the locus drawn by the tip of the upper knife 509 becomes an arc. The ratio D1 / D2 of the present embodiment is increased compared to the ratio of the movement distance between and the movement distance in the direction orthogonal to the axial direction.
The guide grooves 340 and 341 have a shape and a direction in which the upper knife 301 is moved so that the tip of the upper knife 301 draws a locus L. Further, when the upper knife 301 moves from the standby position (open state) to the cutting position, the tip of the upper knife 301 moves away from the left receiving plate 113.
[0059]
Next, the operation of the thread trimming device 37 will be described.
First, an operator or the like sets a workpiece on the feed base 16 facing the origin position and operates a start switch of the sewing machine. Thus, after the feed base 16 has advanced to the sewing start position, it moves along the shape of the eyelet hole to be cut, and the sewing needle 14 and the looper are used to overlock the workpiece. Overlock stitching starts from the front of the left parallel part (the left parallel part of the straight line part) that becomes the eyelet hole, and turns to the rear part of the left parallel part, the round hole part, and the rear part of the right parallel part of the straight part (clockwise) ) Finish sewing at the front of the right parallel part. That is, the front portion of the straight line portion is the sewing end position. It is also possible to carry out over stitching counterclockwise.
[0060]
When the overlock stitching is finished, the feed base 16 moves backward to the cloth cutting position, and then the cloth cutting device 19 is operated to cut and form the eyelet hole composed of the round hole portion and the straight portion in the sewing product.
When the cutting is finished, the left cloth presser device 102 and the right cloth presser device 202 are operated to release the workpiece from being clamped.
In this state, the lower thread 51 and the core thread 52 face each other between the sewing end and the needle plate 21 or the core thread guide mechanism in a state of being stretched substantially in the axial direction of the sewing machine. At this time, as shown in FIGS. 4 and 11, the blade 301 c of the upper knife 301 of the thread trimmer 37 faces the standby position opposite to the blade 302 b of the lower knife 302 with the lower thread 51 and the core thread 52 interposed therebetween. It is out.
[0061]
Next, the cylinder 307 of the thread trimming device 37 is urged in a predetermined direction, and the pawl 310 moves to the left. When the pawl 310 moves to the left, the thread trimmer link arm 311 and the thread trimmer drive arm 312 rotate against the spring 328, and the connecting link 306 slides backward. As the connecting link 306 slides backward, the lower knife link 305 swings and the lower knife 302 rotates. At the same time, the upper knife link 304 swings, and the upper knife 301 moves so that the tip of the upper knife 301 draws a locus L. At this time, as shown in FIG. 12, in the upper knife 301, the blade 301 c approaches the axis of the sewing machine, and the tip of the upper knife 301 avoids the left receiving plate 113 and passes near the left receiving plate 113.
[0062]
At this time, when the connecting link 306 further slides backward, the cloth thread 319 provided at the tip of the upper knife 301 assists in catching the lower thread 51 and the core thread 52 (FIG. 13), and the workpiece is sewn. It is caught in the blade 301c of the upper knife 301 and is prevented from being cut. When the connecting link 306 is further slid rearward, the blade 301c of the upper knife 301 and the blade 302b of the lower knife 302 begin to engage (FIG. 14), and finally the blade 301c and the blade 302b are aligned at the cutting position. The yarn 51 and the core yarn 52 are cut (FIG. 15).
[0063]
The effect of the above thread trimming device 37 is demonstrated.
[0064]
When the upper knife 301 moves from the standby position to the cutting position (matching position), the step screw 316 slides relative to the upper knife 301 along the guide groove 341 and the support shaft 318 moves up the guide groove 340. It slides relative to the knife 301. More specifically, as shown in FIG. 9, when the upper knife 301 moves from the standby position to the cutting position, the step screw 316 moves from one end 341 a side of the guide groove 341 to the other end 341 b side. It moves relative to the upper knife 301. Further, when the upper knife 301 moves from the standby position to the cutting position, the support shaft 318 moves relative to the upper knife 301 from the one end 340a side of the guide groove 340 to the other end 340b side. To do. The step screw 316 and the support shaft 318 are fixed to the right feed plate 201. Therefore, the tip of the upper knife 301 can move so as to draw the locus L. That is, the blade 301c of the upper knife 301 turns while moving backward toward the cutting position and moves toward the cutting position.
[0065]
Therefore, for example, when the upper knife 301 is moved to the cutting position, the tip of the upper knife 301 is moved more than when the upper knife is rotated about the same fulcrum as the rotation fulcrum of the lower knife as in the conventional example. Is positioned more rearward than the front end of the left receiving plate 113. Therefore, the front-rear range (range in the axial direction of the sewing machine) of the engagement between the blade 301c of the upper knife 301 and the blade 302b of the lower knife 302 between the front end and the rear end of the left receiving plate 113 is greater than that of the conventional example. Expanding.
On the other hand, the blade 302b of the lower knife 302 is set to a length that opposes the entire length of the front-rear range.
[0066]
By the way, the end position of the sewing varies depending on the length (sewing length) of the straight portion (parallel portion) of the eyelet hole. If the length of the straight line portion is shortened, the end position of the sewing is further rearward, and if the length of the straight line portion is longer, the end position of the sewing is further forward. In other words, in the eyelet sewing machine 1, the end position of the sewing can be displaced in the axial direction of the sewing machine depending on the length of the straight line portion. In the thread trimming device 37, the front / rear range of the engagement between the blade 301c of the upper knife 301 and the blade 302b of the lower knife 302 is larger than that of the conventional example, so that the lower thread 51 and the core thread 52 are removed from the end of the sewing. The range (cutting range) that can be cut by shortening the length of the extending yarn (the length of the remaining yarn) is expanded before and after the conventional example. Therefore, the corresponding sewing length by which the lower thread 51 and the core thread 52 can be cut by the thread trimming device 37 is widened. The range before and after cutting with the blade 301c of the upper knife 301 and the blade of the lower knife 302b is from the front end of the left receiving plate 113 to the tip of the upper knife 301 when the upper knife 301 and the lower knife 302 are closed to each other. It is the distance before and after.
[0067]
Further, for example, even when the sewing length is increased or decreased and the end position of the sewing is outside the cutting range, the thread trimming device 37 has the lower thread 51 and the core thread 52. Can be cut off. That is, as shown in FIG. 10, in this thread trimming device 37, the right feed plate 201 is formed with mounting holes 322, 322,... Arranged in the front-rear direction (axial direction of the sewing machine). The attachment hole 322 with which the joint portion 303b engages can be changed back and forth, and the attachment position of the thread trimming main body 30 (the upper knife 301 and the lower knife 302) with respect to the right feed plate 201 can be changed. Thereby, the cutting | disconnection range which the thread trimming device 37 can cut | disconnect can be changed back and forth. That is, the lower thread 51 and the core thread 52 are extended from the end of sewing if the front and rear attachment positions of the thread trimming body 30 are changed to the front and rear in accordance with the stitch length of the eyelet hole to be sewn. The yarn can be cut by shortening the length of the yarn (the length of the remaining yarn). In addition, when the attachment hole 322 engaged with the engaging part 303b is changed, the attachment part 306a to which the thread trimming drive arm 312 is attached is changed correspondingly.
[0068]
In addition, since the side edge serving as the blade 302b of the lower knife 302 and the side edge 302c on the opposite side are parallel and the stopper screw 326 is fixed to the right feed plate 201, the thread trimming body as described above. When the attachment position of 30 is changed, it is not necessary to adjust the side edge to be the blade 302b of the lower knife 302 so as to be continuously arranged with the left side edge of the right receiving plate 213.
[0069]
Further, for example, when the blade 302b of the lower knife 302 is sharpened and the distance between the side edge that becomes the blade 302b of the lower knife 302 and the side edge 302c on the opposite side is shortened, the upper knife 301 and the lower knife 302 are When the blade 302b is opened, the blade 302b cannot be disposed continuously with the left edge of the right backing plate 213, and sewing failure occurs during sewing. However, since the stopper screw 326 is slidable to the right and left with respect to the right feed plate 201, the stopper screw 326 can be fixed so that the blade 302b can be continuously arranged with the left edge of the right receiving plate 213.
[0070]
Further, since the upper knife 301 and the lower knife 302 are integrated with the knife mounting portion 303, the upper knife 301 and the lower knife 302 are changed when the mounting positions of the upper knife 301 and the lower knife 302 with respect to the right receiving plate 213 are changed. It is not necessary to adjust the knife pressure between 301 and the lower knife 302.
[0071]
It should be noted that the present invention is not limited to the embodiment described above, and can be variously modified without departing from the scope of the invention. For example, the guide grooves 340 and 341 provided in the upper knife 301 may have a curved shape or a linear shape, and the guide grooves 340 and 341 guide the tip of the upper knife 301 so as to draw a locus L. The shape may be used.
Further, the connecting portions of the upper female link 304, the lower female link 305 and the connecting link 306 may be provided on the connecting link 306 so as to be arranged in the axial direction of the sewing machine at a predetermined interval. This changes the attachment positions of the connecting link 306, the upper female link 304, and the lower female link 305 in accordance with the attachment position of the female attachment portion 303.
The upper knife 301 and the lower knife 302 are moved by the cylinder 307, but may be moved by an actuator such as a solenoid or a motor.
In the above-described embodiment, the thread trimming device 37 of the present invention is applied to the eyelet sewing machine 1, but other buttonhole sewing machines or the thread forming the stitches are sandwiched from the left and right at the sewing end position. The thread trimming device of the present invention can be applied to a sewing machine having an upper knife and a lower knife for cutting and capable of displacing the sewing end position of the thread to be cut over a predetermined range with respect to a straight line direction.
In the above-described embodiment, the thread trimming device 37 is provided on the right feed plate 201. However, a structure may be provided on the left feed plate 101.
[0072]
【The invention's effect】
As described above, according to the first and second aspects of the invention, the thread trimming device can be made compact to expand the thread trimming range.
According to the invention described in claim 3, since the upper knife moves so that the tip of the upper knife draws a locus as described above, for example, the upper knife has the same fulcrum as the pivot point of the lower knife. When the upper knife blade and the lower knife blade are closed, the tip of the upper knife is positioned more rearward than the position corresponding to the front and rear of the front end of the left receiving part, for example. . And the range which can be cut | disconnected with the blade of an upper knife and the blade of a lower knife spreads. Thereby, the remaining thread can be shortened and the thread can be cut corresponding to the longer sewing length.
[0073]
According to the thread trimming apparatus of the invention described in claim 4, when the upper knife moves from the open position to the cutting position, the upper knife is moved along the locus as described above so as to avoid the other backing plate. Since the knife moves, the cutting range that can be cut by the upper knife and the lower knife is expanded backward. Thereby, the remaining thread can be shortened and the thread can be cut corresponding to the longer sewing length.
[0074]
According to the thread trimming device of the fifth aspect of the present invention, since the upper knife is provided with a guide groove having a shape that guides the tip of the upper knife along the locus, the structure of the thread trimming device is as follows. Simplify. Further, since the upper knife is moved along the locus only with two guide grooves and two support shafts, the structure of the thread trimming device is simplified. In addition, similarly to the invention described in claim 3, the upper knife and the lower knife can be used for cutting, and the cutting range is expanded rearward. Thereby, the remaining thread can be shortened and the thread can be cut corresponding to the longer sewing length.
Further, according to the thread trimmer according to the sixth aspect of the invention, since the rotation fulcrum of the lower knife also serves as one of the two fulcrum shafts, the adjustment of the knife pressure is simplified. In addition, similarly to the invention described in claim 3, the upper knife and the lower knife can be used for cutting, and the cutting range is expanded rearward. Thereby, the remaining thread can be shortened and the thread can be cut corresponding to the longer sewing length.
[0075]
According to the thread trimming device of the seventh aspect of the invention, since the attachment position of the female fulcrum member can be changed along the sewing machine shaft direction with respect to the fixed base provided on the feed base, the sewing end point Corresponding to the position (sewing length), the cutting range that can be cut by the blade of the upper knife and the blade of the lower knife can be changed along the sewing machine axis. In addition, when changing the mounting position of the upper knife and lower knife, the upper knife and lower knife remain in the shape of scissors and change in the axial direction of the sewing machine together with the knife fulcrum member. No need to readjust.
[0076]
According to the thread cutting device of the eighth aspect of the present invention, the connection position of at least one of the connecting portion with the upper knife link and the lower knife link and the connecting portion with the drive source is the position of the sewing machine. Because it can be changed along the axial direction, the position of the upper knife and the lower knife can be moved with the upper knife link and the lower knife link in the axial direction of the sewing machine without changing the position of the drive source in the machine axis direction. Can be changed along. That is, the attachment positions of the upper knife and the lower knife can be changed along the axial direction of the sewing machine while maintaining the scissors shape. Accordingly, the cutting range of the upper knife and the lower knife can be changed along the sewing machine shaft in accordance with the sewing end position, and the knife pressure between the upper knife and the lower knife need not be readjusted.
[0077]
According to the thread trimming device of the ninth aspect of the present invention, the second engaging portion is engaged with the plurality of first engaging portions, whereby the female fulcrum member with respect to the fixed base can be configured with a simple configuration. The position of the sewing machine in the axial direction can be changed. Therefore, the axial attachment positions of the upper knife and the lower knife can be changed while being scissors. Accordingly, the cutting range of the upper knife and the lower knife can be changed along the axis of the sewing machine corresponding to the sewing end position, and adjustment of the knife pressure between the upper knife and the lower knife becomes unnecessary. Further, the connecting link includes at least one of a connecting portion with the upper female link and the lower female link and a connecting portion with the driving source, and a plurality of first engaging portions along the axial direction of the sewing machine. Therefore, it is not necessary to change the arrangement position of the drive source along the axial direction of the sewing machine with a simple configuration.
[0078]
According to the thread trimming device of the tenth aspect of the invention, since the stopper that stops the lower knife from moving to the right of the standby position is movable in the direction intersecting the axis of the sewing machine, the lower knife The standby position can be adjusted. In addition, since the side edge that becomes the blade of the lower knife and the side edge opposite to the side edge are parallel, the position of the lower knife is adjusted in advance, and then the upper knife and the lower knife are There is no need to adjust the position of the lower knife when the front / rear position is changed.
[Brief description of the drawings]
FIG. 1 is an overall perspective view showing a schematic configuration of an eyelet hole sewing machine as an example to which the present invention is applied.
FIG. 2 is an exploded perspective view showing a left presser device and a right presser device of the eyelet hole sewing machine.
FIG. 3 is an exploded perspective view showing an example of a thread trimming device according to the present invention.
FIG. 4 is a plan view showing a state in which an upper knife and a lower knife of the thread trimming device are opened from each other.
FIG. 5 is a plan view showing a state in which an upper knife and a lower knife of the thread trimming apparatus are moved to a cutting position.
FIG. 6 is a cross-sectional view showing a main part of the thread trimming device.
FIG. 7 is a view showing a main part of the thread trimming device.
FIG. 8 is a drawing for explaining the locus of the tip of the upper knife of the thread trimming device.
FIG. 9 is a plan view showing a main part of the thread trimming device.
FIG. 10 is a plan view showing a main part of the thread trimming device.
FIG. 11 is a drawing for explaining the operation of the thread trimming device.
FIG. 12 is a drawing for explaining the operation of the thread trimming device.
FIG. 13 is a drawing for explaining the operation of the thread trimming device.
FIG. 14 is a drawing for explaining the operation of the thread trimming device.
FIG. 15 is a view for explaining the operation of the thread trimming device.
FIG. 16 is a plan view showing an example of a conventional thread trimming device.
[Explanation of symbols]
1 Eyelet-cutter sewing machine (button-cutter sewing machine)
16 Feeding base
30 Thread trimming body
31 Drive mechanism (drive source)
51 Lower thread (thread)
52 Core thread (thread)
101 Left feed plate (included in feed base)
112 Presser foot
113 Left receiving plate (receiving portion, other receiving plate)
201 Right feed plate (included in feed base)
213 Right receiving plate (receiving portion, one receiving plate)
301 Upper knife
301c blade (blade of upper knife)
302 Lower knife
302b blade (lower knife blade)
302c Side edge of lower knife (side edge opposite to side edge of lower knife)
303 Female mounting part (Female fulcrum member)
303b engaging portion (second engaging portion)
304 Upper knife link (female moving means)
305 Lower knife link (female moving means)
306 Link (female moving means)
306a Mounting portion (connecting portion with drive source)
307 cylinder
316 step screw (female moving means, support shaft)
318 Support shaft (female moving means, support shaft)
322 mounting hole (first engaging portion)
326 Stopper screw (stopper)
340 Guide groove (female moving means)
341 Guide groove (female moving means)

Claims (10)

A thread of a sewing machine having an upper knife and a lower knife for cutting the thread forming the stitch from the left and right at the sewing end position, and wherein the sewing end position of the thread to be cut can be displaced over a predetermined range in a straight line direction In the cutting device,
A lower knife which is supported so as to be able to rotate in a direction close to the upper knife across a sewing thread with respect to one fixed axis, and which can face the entire displacement range of the sewing end position;
An upper knife which is supported so as to be rotatable in a direction approaching a lower knife with a sewing thread interposed while moving along the straight line direction, and the movement along the straight line direction corresponds to a displacement range of the sewing end position; The sewing machine's thread trimming device. A thread of a sewing machine having an upper knife and a lower knife for cutting the thread forming the stitch from the left and right at the sewing end position, and wherein the sewing end position of the thread to be cut can be displaced over a predetermined range in a straight line direction In the cutting device,
A lower knife which is supported so as to be able to rotate in a direction close to the upper knife across a sewing thread with respect to one fixed axis, and which can face the entire displacement range of the sewing end position;
A thread of a sewing machine comprising: an upper knife supported so as to be capable of rotating in a direction close to a lower knife with a sewing thread interposed while moving along the straight line direction, and an adjustable range of movement along the straight line direction Cutting device. A presser that holds the vicinity of the sewing position of the workpiece,
A feed base that has a receiving portion that sandwiches the sewing product between the presser and moves the sewing product in a sewing direction by placing the sewing product;
A thread of a sewing machine provided with a thread trimmer having an upper knife and a lower knife, which is provided on the feed base side and cuts the thread extending from the sewing end position in the vicinity of the sewing end position after the end of the hole sewing. In the cutting device,
When moving the blade of the upper knife and the blade of the lower knife from the open state to the position where the upper knife is vertically overlapped and closed at the cutting position of the thread, the sewing machine passes the needle position in the locus drawn by the tip of the upper knife. The ratio D1 / D2 of the movement distance D1 in the direction along the axial direction and the movement distance D2 in the direction orthogonal to the axial direction is
A knife moving means for moving the upper knife so that the locus drawn by the tip of the upper knife is larger than that when the upper knife is rotated and moved about the rotation fulcrum of the lower knife as compared to a case where the locus is a circular arc. A thread trimming device for a sewing machine, comprising: In the thread trimming device according to claim 3,
The receiving part is provided in a state divided into left and right receiving plates with the axis of the sewing machine passing through the needle position as a boundary,
With the upper knife and the lower knife open, the lower knife moves the blade of the lower knife near the axis on the front side of one of the left and right receiving plates of the receiving portion. Arranged so as to be substantially along the axis, and the upper knife is arranged so as to extend from the front of one backing plate to the front of the other backing plate,
At the time of cutting the thread, the knife moving means rotates the lower knife so that the blade approaches the axis, and the upper knife moves the blade closer to the axis, and the other of the receiving portions. A thread trimming apparatus for a sewing machine, wherein a tip extending toward the receiving plate is moved along the locus so as to avoid the other receiving plate. In the thread trimming device according to claim 3 or 4,
The upper knife is provided with a guide groove having a longitudinal direction in two different directions,
Two fulcrum shafts inserted respectively into the two guide grooves are provided at the attachment position of the upper knife of the feed base, and the two guide grooves into which the fulcrum shafts are inserted are used when the yarn is cut. A thread trimming device for a sewing machine having a shape for guiding the tip of an upper knife so as to move along the locus. In the thread trimming device according to claim 5,
A thread trimming apparatus for a sewing machine, wherein one of the two fulcrum shafts also serves as a fulcrum for the rotational movement of the lower knife. A button hole sewing machine provided with a feed base for placing the work to be sewn and moving the work in the sewing direction is provided on the feed base side under the work to be sewn. A thread trimming device including an upper knife and a lower knife for cutting a thread extending from a sewing end position of a hole sewing of a sewing product in the vicinity of the sewing end position,
A female fulcrum member having an operating fulcrum between the upper knife and the lower knife;
A sewing machine comprising: a fixing base provided on the feed base, wherein the female fulcrum member is attached, and the attachment position of the female fulcrum member can be changed along the axial direction of the sewing machine. Thread trimming device. The thread trimming device according to claim 7,
A drive source for moving the blade of the upper knife and the blade of the lower knife from a mutually open state to a position where they are overlapped and closed at the cutting position of the thread when cutting the thread;
An upper knife link rotatably connected to the upper knife;
A lower knife link rotatably connected to the lower knife;
A connection link connected to the drive source, connected to the upper female link and the lower female link, and transmitting a driving force to the upper female link and the lower female link, and operating substantially linearly during transmission,
In the connection link, at least one of the connection part between the upper female link and the lower female link and the connection part with the driving source can be changed in the connection position substantially along the axial direction of the sewing machine. A thread trimming device for a sewing machine, characterized in that The thread trimming device according to claim 8,
One of the fixed base portion and the female fulcrum member is provided with a plurality of first engaging portions for positioning the other side by side along the axial direction of the sewing machine. A second engagement portion is provided to engage with the engagement portion,
In the connection link, at least one of a connection portion between the upper female link and the lower female link and a connection portion with the drive source corresponds to the plurality of first engagement portions. A plurality of thread trimming devices for a sewing machine, wherein a plurality of the thread trimming devices are arranged along the axis of the sewing machine. In the thread trimming device according to any one of claims 7, 8, and 9,
In a state where it is arranged at the standby position before cutting, the side edge serving as the blade of the lower knife is arranged in a direction substantially along the axis of the sewing machine, and the side opposite to the side edge serving as the blade of the lower knife Formed so that the edge is parallel to the side edge of the blade,
A sewing machine thread trimming apparatus comprising: a stopper that stops the lower knife from moving to the right of the standby position and is movable in a direction that intersects the axis of the sewing machine.

Images