JP4286037B2 - Thread trimming holding device for chain stitch machine - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a thread trimming holding device for cutting a sewing thread between a saddle needle and a looper after a sewing operation and holding a thread end of the cut sewing thread in a chain stitch sewing machine.
[0002]
[Prior art]
Patent Document 1 describes an apparatus for cutting a sewing thread between a saddle needle and a looper with a movable knife and a fixed knife in a chain stitch sewing machine. This thread trimming holding device is provided with a thread retaining member that retains the looper side thread end of the sewing thread immediately after thread trimming in order to reliably thread the heel needle at the time of sewing. The thread holding member includes a holding plate formed by bending a leaf spring, the base end of the holding plate is fixed to the lower support plate, the free end of the holding plate is elastically contacted with the upper support plate, and the upper support plate And the holding plate are configured to hold the yarn end.
[0003]
[Patent Document 1]
JP-A-8-103590 [0004]
[Problems to be solved by the invention]
However, according to the conventional thread trimming holding device, since the holding plate is covered with the upper support plate, it is necessary to remove the upper support plate when checking the operating condition of the holding plate. In addition, although the holding plate and its surroundings are likely to be clogged with fiber wastes of the sewing thread, it is necessary to remove the upper support plate when removing this, and there has been a problem that the maintenance is generally troublesome.
[0005]
An object of the present invention is to solve the above-described problems and provide a thread trimming holding device for a chain stitch sewing machine that can easily perform maintenance of a thread holding member.
[0006]
[Means for Solving the Problems]
In order to solve the above-described problems, the thread trimming holding device of the present invention is a device for cutting a sewing thread between a needle and a looper after sewing is completed and holding a thread end of the cut sewing thread in a chain stitch sewing machine. A board is installed on the bed so as to cover the upper surface, a guide plate is mounted on the board, and a movable knife capable of moving forward and backward relative to the looper is provided between the board and the guide plate in a horizontal plane. A driving means for reciprocating the movable knife after sewing is provided, and a gate-shaped mounting base having an opening through which the movable knife can pass is mounted on the upper surface of the board, and the front end portion is inclined obliquely forward. Attach the rear end of a fixed knife that is bent into a shape and engages with a movable knife that is moving backward at the lower edge of the front edge to cut the sewing thread, covers the periphery of the looper from above, and the looper appears and disappears Possible through hole The looper cover with the formed covering portion is provided, a thread holding member for holding the yarn end of the cut thread, is integrally formed on the rear edge of the cover portion, the position of the rear side of the blade portion of the movable knife, And a thread catcher that receives the thread end at a position below the movable knife, a thread retainer that faces the thread retainer from above , and a post that is erected on the thread retainer and supports the thread retainer so that the thread retainer can be opened and closed. And a spring that urges the thread presser in the closing direction, and a bed cover that covers each of the bed, the substrate, the guide plate, the movable knife, the fixed knife, and the thread holding member is removably attached to the table. When the bed cover is removed, the thread presser and the fixing knife exposed on the upper surface of the thread receiver appear .
[0007]
Here, in order to open and close the thread presser smoothly, the left and right struts are erected on the thread receiver with a space through which the movable knife can pass, and each spring is elastically brought into contact with the upper surface of the thread presser as the spring. It is preferable to insert a spring. In addition, it is preferable to provide an engagement portion that engages with the movable knife in the middle of the thread presser so that the thread end can be released from the thread holding member by the movable knife.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment in which the present invention is embodied in a chain stitch sewing machine for embroidery processing will be described with reference to the drawings. First, the overall configuration of the chain stitch sewing machine will be outlined. As shown in FIG. 1, the chain stitch sewing machine has a multi-head configuration in which a plurality of heads 2 are provided on the upper frame 1. A needle bar 3 is supported on each head 2 so as to be able to move up and down, and a needle 4 is attached to the lower end of the needle bar 3. The needle bar 3 is connected to a motor 6 through a main shaft 5 common to all heads 2, and the needle 4 is driven up and down as the motor 6 rotates. Further, the needle bar 3 is rotated around a lifting / lowering axis via a direction control shaft by a motor (not shown), and the direction of the heel needle 4 is controlled in accordance with the sewing direction.
[0009]
A table 8 is disposed below the head 2, and the same number of beds 10 as the head 2 are installed on an intermediate frame 9 below the table 8. A looper support 11 is provided on the front surface of each bed 10 so as to be movable in the left-right direction. Six loopers 12 (see FIG. 2) and a yarn feeding apron 13 are provided on the support 11. Each support body 11 is connected to a color changing mechanism 15 via a connecting shaft 14, and indexing means for selectively indexing one looper 12 to a sewing position facing the heel needle 4 by the color changing mechanism 15 is configured.
[0010]
A thread stand 18 is provided on the lower frame 17 below the bed 10, and the same number of thread windings 19 as the looper 12 are arranged on the thread stand 18. Each thread spool 19 is wound with a thread T of a different color and is supplied to the looper 12 via a thread guide 20 on the lower frame 17, a thread tension 21 on the yarn feeding apron 13, and thread guides 22 and 23. A multicolored embroidery pattern composed of an annular stitch is sewn on the work cloth on the table 8 by the cooperation of the looper 12 and the heel needle 4 that are indexed at the sewing position.
[0011]
Next, the configuration of the peripheral part of the bed 10 will be described. As shown in FIG. 3, a bed cover 30 that covers the upper surface of the bed 10 is attached to the table 8, and a needle plate 25 having a needle hole 24 (see FIG. 4) is provided on the cover 30. A looper support 11 is disposed on the lower side. A slider 26 is attached to the rear surface of the looper support 11, and a rail 27 on which the slider 26 is fitted is fixed to the front surface of the bed 10 so as to extend left and right. The yarn feeding apron 13 is attached to the lower part of the front surface of the looper support 11, and the connecting shaft 14 is coupled to the cylindrical portion 28 of the yarn feeding apron 13 with bolts 29.
[0012]
As shown in FIGS. 2 and 3, a looper drive motor (servo motor) 31 and a female drive motor (pulse motor) 32 are arranged side by side in the bed 10, and the front wall of the bed 10 is held by a holding plate 33. 34 and the inner wall 35. A drive gear 37 is supported on the holding plate 33 by a shaft 36 and is connected to an output shaft 39 of the looper drive motor 31 via a pinion 38. A looper elevating motor (pulse motor) 40 is installed inside the intermediate frame 9, and its output shaft 41 is connected to an elevating body 44 via an eccentric cam 42 and a lever 43.
[0013]
As shown in FIGS. 4 and 5, each of the six loopers 12 is fixed to the upper end of the looper shaft 47, and the looper shaft 47 is supported in a vertical hole 48 of the looper support 11 so as to be movable up and down. A horizontal U-shaped looper cover 46 is attached to the upper end of the looper support 11 with screws 45 at left and right leg portions 46a. The looper cover 46 is provided with a covering portion 46b that covers the periphery of each looper 12 from above, and six through holes 57 in which the looper 12 can protrude and retract are formed in the covering portion 46b. The covering portion 46 b is attached to the support 11 so as to be positioned at substantially the same height as the upper surface of the looper 12 in the lowered position, and the through hole 57 is closed by the looper 12.
[0014]
The looper 12 is provided with a needle drop hole 53, a thread feeding hole 54, a looper gear 55, and a notch 56. The looper shaft 47 is formed in a hollow shape, and the sewing thread T is inserted from the threading hole 58 of the yarn feeding apron 13 into the looper shaft 47, the thread feeding hole 54, and the through hole 57 and pulled out to the upper side of the covering portion 46b of the looper cover 46. It is. A rotating body 50 is supported at a lower end portion of the looper shaft 47 via a bearing 49, and a compression spring 51 for biasing the looper shaft 47 downward is interposed between the rotating body 50 and the looper support body 11. Yes.
[0015]
When the looper lifting / lowering motor 40 rotates, the lifting / lowering body 44 engages with the rotating body 50 on one looper shaft 47 indexed to the sewing position from below, and the looper shaft 47 resists the urging force of the compression spring 51. Then, the looper 12 on the looper shaft 47 is disposed at a raised position (a chain line position in FIG. 4) approaching the lower surface of the needle plate 25. Then, the looper gear 55 is engaged with the drive gear 37, the looper 12 is rotated by the drive motor 31, and the sewing thread T is hooked on the heel needle 4 that has entered the needle drop hole 53 (see FIG. 9).
[0016]
A long strip 59 is attached to the left and right on the front upper portion of the looper support 11, and six pins 60 are inserted into the strip 59 so as to protrude rearward along the upper end surface of the looper support 11. Yes. The five loopers 12 other than the sewing position are held at a lowered position (solid line position in FIG. 4) in contact with the upper end surface of the support 11 by the urging force of the compression spring 51. Then, the looper gear 55 is disconnected from the drive gear 37, and the rotation of the looper 12 is restricted by the fitting of the notch 56 and the pin 60.
[0017]
Next, the configuration of the thread trimming holding device will be described. As shown in FIGS. 2 and 5, the substrate 63 of the thread trimming holding device 62 is installed on the bed 10 so as to cover the upper surface thereof. A flexible plate 64 made of rubber, felt or the like is laid on the substrate 63 at the same height as the covering portion 46b of the looper cover 46, and a guide plate 65 is mounted on the flexible plate 64 in an overlapping manner. A guide groove 66 is recessed in the lower surface of the guide plate 65 so as to extend in the front-rear direction. A movable knife 67 can move forward and backward relative to the looper 12 at the sewing position on the flexible plate 64 inside the guide groove 66. Is provided.
[0018]
A pin 69 protrudes from the middle portion of the movable knife 67 in the longitudinal direction, and a slit 70 is formed in the guide plate 65 so as to expose the pin 69 upward. An arm 73 is coupled to the output shaft 71 of the knife drive motor 32 via a shaft holder 72, and a long hole 74 for connecting a pin 69 is formed at the tip of the arm 73. After the end of sewing, the movable knife 67 is reciprocated back and forth via the arm 73 by a knife drive motor 32 as a drive means. The bed 10 is provided with an origin sensor 75 for detecting the retracted end position of the movable knife 67, and a dog 76 for operating the sensor 75 is provided on the shaft holder 72.
[0019]
As shown in FIGS. 5 and 6, a fixed knife 78 is attached to the upper surface of the front end portion of the substrate 63 with a screw 80 via a mounting base 79. The mounting base 79 is formed in a gate shape and includes an opening 82 through which the movable knife 67 can pass. The fixed knife 78 is formed in a plane T shape, the rear end portion is fixed to the mounting base 79, and the front end portion is bent in a slanted shape with a front lowering. A blade portion 84 which is a cutting portion of the thread trimmer holding device 62 is formed on the lower edge of the front end of the fixed knife 78, and the movable knife 67 in the middle of retraction engages the blade portion 84 to cut the sewing thread T. On the upper surface of the covering portion 46 b of the looper cover 46, the same number of yarn guide grooves 85 as the looper 12 are formed so as to extend rearward from the through hole 57.
[0020]
Further, on the upper surface of the rear edge portion of the covering portion 46b , six thread holding members 87 for holding the thread end E of the cut sewing thread T on the looper 12 side are arranged in a row in the indexing direction (left-right direction) of the looper 12. Are arranged side by side. Each thread holding member 87 includes a thread receiver 86 as a fixed part that receives the thread end E at a position below the movable knife 67, a thread retainer 88 as a movable part facing the thread receiver 86 from above, and a thread retainer 88. Is composed of a support 89 that supports the thread receiver 86 so that it can be opened and closed up and down, and a compression spring 90 that urges the thread retainer 88 in the closing direction. The yarn receiver 86 is integrally formed on the rear edge of the covering portion 46b so as to be joined to the front end portion of the substrate 63 from above.
[0021]
Two struts 89 are erected on the left and right sides with an interval through which the movable knife 67 can pass through the thread receiver 86. The thread retainer 88 is made of a strip-shaped thin steel plate, and is provided with a hole 91 to be inserted into the support column 89 and an oblique engagement portion 92 that opens rearward toward the rear side. The compression spring 90 is fitted and inserted into each support 89 so as to elastically contact the upper surface of the thread retainer 88 and is prevented from coming off by a locking ring 93. Then, while the movable knife 67 is moving forward, the front end of the movable knife 67 engages with the engaging portion 92 to open the thread retainer 88. When the movable knife 67 is retracted, the thread retainer 88 is closed by the restoring force of the compression spring 90. ing. The thread guide groove 85 passes through the blade portion 84 and extends to the vicinity of the front edge of the thread presser 88.
[0022]
According to the above configuration, the thread retainer 88 is supported by the pair of left and right struts 89, and the compression springs 90 (compression coil springs in this example) are respectively inserted into the respective struts 89. Opening and closing smoothly, the yarn end E can be securely held and released. Further, since the thread retainer 88 is exposed on the upper surface of the looper cover 46, if the bed cover 30 is removed from the table 8, the operation state of the thread retainer 88 can be checked at a glance, and the fiber waste adhering to the thread retainer 88 is removed. The thread holding member 87 can be maintained in a short time because it can be easily cleaned.
[0023]
In addition, since the covering portion 46b of the looper cover 46 covers the six loopers 12 from above, and the through holes 57 of the covering portion 46b are closed by the looper 12, the fiber waste that comes out along with thread trimming is covered with the covering portion 46b. The parts on the looper support 11 such as the looper gear 55, the slider 26, the rotating body 50, the thread tension 21, and particularly the movable parts can be protected from fiber waste. In addition, since the yarn holding member 87 is arranged on the upper surface of the covering portion 46 b and a part of the covering portion 46 b is used as the yarn receiver 86, the looper cover 46 functions as a part of the yarn trimming holding device 62. There is also an advantage that the number of parts of the thread trimming holding device 62 can be reduced.
[0024]
As shown in FIG. 7, a blade 97 that engages with the blade 84 of the fixed knife 78 and cuts the sewing thread T while the movable knife 67 is retracted is formed at the center of the front end portion of the movable knife 67. . On the rear side of the blade portion 97, a capturing portion 96 that captures the sewing thread T when the movable knife 67 moves forward is provided. An arcuate guide portion 95 is provided at the front edge of the movable knife 67, and as the movable knife 67 advances, the sewing thread T is guided around the blade portion 97 to the catching portion 96. The blade portion 97 is formed in an acute angle at the front upper edge of the circular hole 94 inclined later, and a rearwardly inclined surface 98 is provided from the blade portion 97 to the capturing portion 96.
[0025]
On the upper surface of the front end of the movable knife 67, a slanting surface that is forwardly lowered is formed as a release portion 99 that releases the holding state of the yarn end E by the yarn presser 88 of the yarn holding member 87. In this example, since the slanted engaging portion 92 is provided on the thread retainer 88, the angular edge of the front upper end of the movable knife 67 may be used as the releasing portion. However, the slanted surface or the front-lowering rounded surface instead of the inclined surface is preferable in that it can be engaged smoothly. Further, the concave portion 100 is provided on the lower surface of the front end of the movable knife 67 so as to expand to the vicinity of the blade portion 97 except for a part overlapping the release portion 99. Then, at the initial stage of sewing, the knife drive motor 32 stops the movable knife 67 at a position in the middle of advancement (see FIG. 8 b), and engages the release portion 99 with the engagement portion 92. Thereby, the release part 99 opens the thread retainer 88 as a movable part, and at this time, the recessed part 100 is configured to escape the thread end E from the space between the thread receiver 86 (see FIG. 9b). According to this configuration, since the movable knife 67 has both the sewing thread cutting function and the thread end releasing function, a dedicated releasing member is not required, and the thread trimming holding device 62 can be easily configured with a small number of parts. .
[0026]
Next, the operation of the thread trimming holding device 62 configured as described above will be described. When the chain stitch machine is stopped, as shown in FIG. 9A, the movable knife 67 is disposed at the retracted end position (see FIG. 8A), and the release portion 99 is housed in the opening 82 of the mounting base 79. The sewing thread T is pulled out from the thread feeding hole 54 of each looper 12 to the upper surface of the looper cover 46, and the thread end E is held between the thread receiver 86 and the thread presser 88 of the thread holding member 87. In this state, one looper 12 is indexed to the sewing position by the color changing mechanism 15, and then raised by the looper lifting / lowering motor 40 via the lever 43 and the lifting / lowering body 44.
[0027]
When the sewing starts, the looper 12 rotates and the sewing thread T is applied to the sewing needle 4 in a state where the sewing needle 4 is lowered into the needle drop hole 53, and the sewing needle 4 pulls up the sewing thread T as shown in FIG. An annular seam is formed on the work cloth W. When, for example, two or three stitches are formed at the initial stage of sewing, the knife drive motor 32 rotates forward, the arm 73 swings, and the movable knife 67 moves forward. Then, at the midway position of the movable knife 67 (see FIG. 8b), the release portion 99 at the front end engages with the engagement portion 92 to open the thread retainer 88, and then the knife drive motor 32 stops. Thereby, the holding state of the yarn end E by the yarn holding member 87 is released.
[0028]
Sewing is continued in this state, and the thread end E escapes forward from the thread retainer 88 as the work cloth W is fed, as shown in FIG. At this time, since the recess 100 is formed on the lower surface of the front end of the movable knife 67, the thread end E is smoothly pulled out from the thread holding member 87 without being compressed between the thread receiver 86 and the thread presser 88. Therefore, there is no possibility that the seam is tightened in the initial stage of sewing, and a clean embroidery pattern with a uniform seam size can be processed. When the thread end E comes off, the knife drive motor 32 rotates in the reverse direction, the movable knife 67 returns to the retracted end position, and the thread presser 88 closes.
[0029]
When the sewing is finished, as shown in FIG. 10A, the looper 12 stops at a phase where the upper end of the thread feeding hole 54 faces the blade portion 84 of the fixed knife 78, and then the height of the looper cover 46 is substantially the same as the upper surface. Descend to In this state, the knife drive motor 32 rotates forward, the movable knife 67 moves forward, the release part 99 opens the thread retainer 88, and the guide part 95 sends the sewing thread T between the saddle needle 4 and the looper 12 to the blade part 97. Detour to the side and guide to the capture unit 96 side. When the pin 69 of the movable knife 67 contacts the front end of the slit 70 of the guide plate 65, the movable knife 67 stops at the forward end position (see FIG. 8c), the knife drive motor 32 rotates in the reverse direction, and the movable knife 67 Retreats.
[0030]
When the movable knife 67 is retracted, as shown in FIG. 10B, the catching portion 96 catches the sewing thread T and pulls it backward from the blade portion 84 of the fixed knife 78 along the thread guide groove 85 of the looper cover 46. The blade portion 97 of the movable knife 67 engages with the blade portion 84 of the fixed knife 78 to cut the sewing thread T. At this time, since the thread guide groove 85 extends from the through hole 57 of the looper cover 46 toward the blade portion 84 of the fixed knife 78, the sewing thread T can be reliably cut without being removed from the blade portions 84 and 97. . Thereafter, as shown in FIG. 10C, the release portion 99 passes through the thread holding member 87, the thread retainer 88 is closed by the spring force of the compression spring 90, and the thread end E on the looper 12 side of the cut sewing thread T. Hold. Then, at the initial stage of the next sewing, the holding state of the thread end E is released as described above.
[0031]
In addition, this invention is not limited to the said embodiment, For example, it can also be suitably changed and embodied as follows, for example in the range which does not deviate from the meaning of invention.
(1) Use a sector knife capable of reciprocating rotation as the movable knife.
(2) The movable knife is linearly moved by a motor via a rack and pinion.
(3) The thread retainer of the thread holding member is supported by a single support so that it can be opened and closed in a cantilevered state.
(4) Provide both a thread retainer and a thread receiver for the thread holding member so as to be movable up and down.
(5) The thread trimmer holding device of the present invention is applied to a single-head chain stitch machine.
(6) The thread trimmer holding device of the present invention is applied to a single looper sewing machine that does not have a color changing function.
[0032]
【The invention's effect】
As described above in detail, according to the thread trimming holding device of the chain stitch sewing machine according to the present invention, the thread presser is provided so as to face the thread receiver from above, so that the thread holding member can be easily maintained. There is an excellent effect.
[Brief description of the drawings]
FIG. 1 is a front view of a multi-headed chain stitch sewing machine showing an embodiment of the present invention.
2 is a plan view of a bed portion of the chain stitch sewing machine of FIG. 1; FIG.
3 is a cross-sectional view taken along line III-III in FIG.
4 is a cross-sectional view taken along line IV-IV in FIG.
5 is a perspective view showing a thread trimming holding device of the chain stitch sewing machine of FIG. 1; FIG.
6 is an exploded perspective view showing a yarn holding member of the yarn trimming holding device of FIG. 5. FIG.
7 is an explanatory view of the shape of the front end portion of the movable knife in the thread trimming holding device of FIG. 5. FIG.
FIG. 8 is a plan view of the thread trimming holding device showing the operation of the movable knife.
9 is a cross-sectional view of a principal part showing an operation of the thread trimming holding device of FIG. 5 in an initial stage of sewing.
10 is a cross-sectional view of the main part showing the operation of the thread trimmer holding device of FIG. 5 after completion of sewing.
[Explanation of symbols]
2 Head 4 Acupuncture needle 8 Table 10 Bed 11 Looper support 12 Looper 31 Looper drive motor 32 Female drive motor 37 Drive gear 40 Looper lifting motor 43 Lever 44 Lifting body 46 Looper cover 47 Looper shaft 55 Looper gear 62 Thread trimmer holding device 63 Substrate 67 Movable knife 73 Arm 78 Fixed knife 79 Mounting base 84 Blade part 85 Thread guide groove 86 Thread receiver 87 Thread holding member 88 Thread presser 89 Strut 90 Compression spring 92 Engagement part 97 Blade part 99 Release part E Thread end T Sewing thread

Claims (3)

In a chain stitch sewing machine, a device that cuts the sewing thread (T) between the saddle needle (4) and the looper (12) after the end of sewing and holds the thread end (E) of the cut sewing thread,
A substrate (63) is installed on the bed (10) so as to cover the upper surface thereof,
A guide plate (65) is mounted on the substrate (63),
A movable knife (67) is provided between the substrate (63) and the guide plate (65) that can move forward and backward with respect to the looper (12) in a horizontal plane.
Drive means (32) for reciprocating the movable knife (67) after the end of sewing is provided,
A gate-shaped mounting base (79) having an opening (82) through which the movable knife (67) can pass is attached to the upper surface of the substrate (63) .
A blade portion (84) for cutting the sewing thread (T) by engaging the movable knife (67) in the middle of retreating at the front end lower edge, with the front end portion being bent in a slanted shape with the front end lowered on the mounting base (79). Attach the rear end portion of the formed fixed knife (78),
A looper cover (46) provided with a covering portion (46b) that covers the periphery of the looper (12) from above, and has a through hole (57) in which the looper (12) can protrude and retract, is provided.
A thread holding member (87) for holding the thread end (E) of the cut sewing thread (T) is integrally formed on the rear edge of the covering part (46b), and the blade part (84) of the movable knife (67). A thread catcher (86) that receives the thread end (E) at a rear position and a position below the movable knife (67); a thread retainer (88) that faces the thread catcher (86) from above; and a thread receiving (86) to be erected, thread presser (88) receiving the thread (86) and struts (89) which openably supported with respect, thread presser (88) spring biasing the closing direction (90) And consisting of
A bed cover (30) which covers each member of the bed (10), the substrate (63), the guide plate (65), the movable knife (67), the fixed knife (78) and the thread holding member (87) on the table (8). The thread trimmer of the chain stitch sewing machine is characterized in that the thread presser (88) exposed to the upper surface of the thread receiver (86) and the fixed knife (78) appear when the bed cover is removed and the bed cover is removed. Holding device. The left and right struts (89) are erected on the thread receiver (86) with an interval through which the movable knife (67) can pass, and each strut (89) serves as the spring (90) as a thread presser (88). The thread trimming holding device for a chain stitch sewing machine according to claim 1 , wherein a compression spring (90) elastically contacting the upper surface of the sewing machine is inserted. 3. The chain stitch sewing machine according to claim 1, wherein the thread retainer (88) is provided with an engaging portion (92) engaged with a movable knife (67) in the middle of advancement in a slanted shape that opens rearward toward the rear side. Thread trimmer holding device.

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