JP2009095616A - Thread chain sewing method and thread chain sewing device of sewing machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a thread chain sewing method and a thread chain sewing device of a sewing machine by which the structure can be simplified and obstruction of operations, hindrance to vision and the like can be eliminated, and, in addition to this, the thread chains can be sewn into a seam of the sewing start edge of a next material to be sewn reliably and smoothly. <P>SOLUTION: The thread chains 12 which are sucked into a suction pipe 11 of the thread chain sewing device 10 and are cut are blown back and moved through between a needle 15 and a trimmer 2 for cutting the cloth end. At the same time, the end of the thread chains 12 which are blown back and moved is moved toward the side of a thread chain holding device 16 which is arranged before the needle location 14 by an auxiliary airflow which is spewed out from the back and lateral position toward the front and lateral position with respect to the blowing back movement trajectory of the thread chains 12 and is held by the device 16. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a sewing machine and a sewing machine for sewing, such as a knit T-shirt, outwear, and underwear. Specifically, at the end of sewing of the sewing fabric, the empty ring formed continuously with the stitch forming claw portion of the needle plate is drawn into the stitches at the sewing start end of the sewing fabric as the next sewing fabric starts sewing. The present invention relates to an empty ring stitching method and an empty ring stitching device for a sewing machine which are designed to prevent fraying at the sewing start end by performing so-called back tack sewing.

  As this kind of empty ring stitching device, conventionally, an empty ring connected to the stitch forming claw portion of the needle plate at the end of sewing of the sewing fabric is connected to an air source such as a vacuum pump (not shown) rather than the needle drop portion. Suction into a suction pipe of an empty ring cutting device provided on the rear side in the sewing progress direction, cut from the sewing fabric in the suction pipe, and the cut empty ring is generated in the suction pipe via the air source. The air ring suction nozzle that receives and sucks back the air ring that is blown back from the suction port at the tip in the direction opposite to the sewing progress direction is used as a fulcrum on the right side of the needle plate The reciprocating drive is swingable back and forth in the front-rear direction, and this blank ring suction nozzle is cut from the end of the cloth provided at the front (front) part of the needle plate near the base end of the stitch forming seam from the position where the blown back ring ring is received. Retreats to the position near the scalpel After moving through an intermediate stop position, the reverse movement of the intermediate stop position is further reversed in the direction opposite to the sewing progress direction, so that the empty ring sucked and held by the empty ring suction nozzle is placed in front of the needle drop portion. There is known a structure that is held in a tensioned state on the side and pulled into a seam at a sewing start end portion of the next sewing fabric (for example, see Patent Document 1).

  Further, as shown in FIG. 11, the empty ring 12 that is sucked into the empty ring suction pipe 11 of the empty ring cutting device 10 and cut from the sewing fabric is reversed from the suction port 11 a at the tip of the suction pipe 11 in the direction of the sewing progress. The needle 15 is caused by an air flow (airflow) ejected toward the left side of a needle 15 (shown by two needles but may be a single needle) that moves up and down with respect to the needle drop portion 14 of the needle plate 13 in the direction. The air pipe provided on the left side of the needle drop portion 14 toward the end of the empty ring 12 that has been blown back is blown back and moved to the upper surface portion of the needle plate 13 diagonally to the left of the needle 15. By blowing an auxiliary air flow (auxiliary air flow) ejected from a nozzle (not shown) or the like, the end of the empty ring 12 blown back through a trajectory as shown by the thick arrow A is located in front of the needle drop portion 14. An empty space provided on the right side of the needle plate 13 Some are configured to move toward the holding device 16 to be held by the holding device 16 and to be pulled into the stitches at the sewing start end of the sewing fabric when the next sewing fabric is sewn. Known (see, for example, Patent Documents 2 and 3).

  Japanese Patent No. 3567274   Japanese Patent Publication No. 5-28160   Japanese Utility Model Publication No. 5-40877

  Among the above-described conventional empty ring stitching devices, in the case of the former device known from Patent Document 1 etc., the sewing progress is made on the right side portion of the needle plate more than the above-mentioned empty ring receiving advance position and needle dropping portion. Since a movable idle ring suction nozzle that can swing back and forth between the retreat position forward in the direction is installed, it is not only structurally complicated but also reciprocating drive swing at the right side of the needle plate. There is a problem that the movable idle ring suction nozzle that moves easily disturbs the sewing work, and also that it easily becomes a visual obstacle when the operator performs the sewing work while looking at the sewing condition.

  On the other hand, in the case of the latter device known from Patent Documents 2 and 3, etc., the empty ring is blown back from the suction / cutting of the empty ring in the direction opposite to the sewing progress direction, and the empty ring holding device at the end of the empty ring All the air ring movement processing is performed by air flow until moving and holding to the side, and it is not necessary to install a movable air ring suction nozzle, so it is structurally simple, obstructing work and visually disturbing However, while the latter apparatus can solve the problems of the former apparatus, the following problems remain unsolved.

  That is, in the latter device, as clearly shown in FIG. 12, the empty ring 12 formed continuously with the stitch forming claw portion 13a of the needle plate 13 passes through the left side of the needle 15 and before the needle drop portion 14. Since it is held by the empty ring holding device 16 provided on the right side portion of the side needle plate 13, the needle thread 17 located at the needle drop portion 13 a is pushed and bent by the empty ring 12 in a reverse letter shape. It will be. Therefore, when the needle 15 moves up and down at the start of the next sewing, a tension is generated in the needle thread 17, and the portion 12 a of the empty ring 12 that has moved to the right side of the needle drop portion 14 due to the tension is the needle drop portion 14. When the needle 15 is lowered in this state, the needle 15 passes through the empty ring portion 12a in the retracted state to form a seam. As shown in FIG. 13, there is a problem in that it is not sewn into the seam 19 of the sewing fabric 18, and causes a sewing failure such that the sewing fabric 18 protrudes and remains in a dumpling shape at the front edge portion 18 e of the sewing start end portion. It was.

  The present invention has been made in view of the above-described circumstances. In addition to simplifying the structure and eliminating the hindrance to the work and the visual obstacle, the empty ring is inserted into the seam at the sewing start end of the next sewing fabric. It is an object of the present invention to provide an empty ring stitching method and an empty ring stitching device for a sewing machine that can be securely and smoothly sewn.

  In order to achieve the above-described object, the sewing machine according to the present invention includes a sewing method for sewing an empty ring formed continuously to a stitch forming claw portion of a needle plate at the end of sewing of a sewing fabric rather than a needle drop portion. The needle is sucked into a suction pipe of an empty ring cutting device provided on the rear side in the advancing direction and cut from the sewing fabric, and the end of the cut empty ring is blown in a direction opposite to the sewing advancing direction. Blow back to the front side of the drop part, and hold the end of the idle ring moved back by the empty ring holding device provided on the front side of the needle drop part, along with the start of sewing of the next sewing fabric, The sewing machine is a method for empty-ring stitching of a sewing machine that is pulled into a seam at a sewing start end portion of the sewing fabric, and sews the end portion of the empty ring that is sucked into the suction pipe of the idle-cutting device and cut. Needle that moves up and down with respect to needle entry point and front Blows back toward the front side of the needle drop part along the upper surface of the needle plate between the knife for cutting the fabric edge and provided near the base end of the nails for forming the seam. The end of the air ring that has been moved back and moved is retained by the auxiliary air current that is blown out from the rear side position in the direction of sewing with respect to the air ring rewind movement trajectory and crossed obliquely to the front side. The apparatus is characterized in that it is moved to a holding position by the apparatus and held (claim 1).

  In addition, the sewing machine of the present invention includes an empty ring stitching device connected to the stitch forming claw portion of the needle plate at the end of the sewing of the sewing fabric, and a rear side of the sewing advance direction from the needle drop portion. Suction into the suction pipe of the empty ring cutting device provided on the sewing machine and cut from the sewing fabric, and the end of the cut empty ring is on the front side of the needle drop part by an air flow blown in the direction opposite to the sewing progressing direction. The end of the empty ring that has been moved back is held by an empty ring holding device provided on the front side of the needle drop portion, and the sewing of the sewing fabric is started as the next sewing fabric starts sewing. A hollow ring stitching device for a sewing machine configured to be pulled into a seam at a start end portion and to be sewn, wherein the leading end portion of the suction pipe of the blank ring cutting device is sucked into the suction pipe and cut. The end of the hollow ring Then, along the needle plate upper surface portion between the needle that moves up and down and the cloth edge cutting knife that is provided near the base end of the seam forming claw part and trims the edge of the sewing cloth. An air flow outlet for blowing back to the front side of the needle drop part is formed, and a side part of the needle drop part is provided to the front side of the needle drop part by an air flow from the blow outlet part. The end of the idle ring that has been blown back is moved to the holding position by the idle ring holding device and held so as to cross obliquely forward from the rear side position in the sewing progress direction with respect to the blow-back movement locus of the idle ring. And an auxiliary airflow ejection device for ejecting the auxiliary airflow is provided (claim 3).

  According to the empty ring stitching method and the empty ring stitching device of the sewing machine according to the present invention having the above-described characteristic configuration, the idle ring cutting device sucks after being formed continuously with the stitch forming claw portion of the needle plate. The empty ring sucked into the tube and cut is blown back along the upper surface of the needle plate between the needle and the knife for cutting the fabric end by the air current blown from the outlet at the tip of the suction tube. The end of the air ring that has been blown back is moved to the side of the air ring holding device in front of the needle drop portion by the auxiliary air current that is blown across the trajectory of the air ring rewinding movement and is held by the air ring holding device. As shown in the figure, the movement of all the empty rings from the suction / cutting of the empty rings to the reverse of the sewing progress direction and the movement and holding of the end toward the empty ring holding device are performed. Because it is done through airflow Installation of such air ring suction nozzle movable is not required, along with simplification of structure, it is possible to improve the workability by eliminating disturbing and blind sewing operation.

  Moreover, it is possible to finally hold the empty ring through the right side of the needle in the empty ring holding device without causing any interference with the needle thread, so that the needle passes through the empty ring at the next sewing. Can be reliably avoided. Therefore, the empty ring can be sewed reliably and smoothly into the seam at the sewing start end of the next sewing fabric without mistake, and a part of the empty ring is dumped on the front edge of the sewing start end of the sewing fabric. Thus, it is possible to reliably prevent the occurrence of sewing defects such as protruding and remaining.

  An opening formed in the cross plate substantially flush with the throat plate near the side of the throat plate as the auxiliary airflow ejecting device in the vacant stitching method and vacant stitching device of the sewing machine according to the present invention having the above-described configuration. A cap-like air valve that can be switched between a state of projecting upward and a state of retracting downward through the cross plate, and an air flow introducing means for introducing a pressurized air flow into the air valve; An air flow ejection hole formed on the side wall of the upper end portion of the air valve, and when the air valve protrudes upward from the cross plate, the pressurized air flow introduced into the air plate is ejected along the upper surfaces of the cross plate and the needle plate; It is preferable to use what comprises (Claim 2 and Claim 4).

  In this case, the air valve is set on the cross plate only when an auxiliary air current is ejected that moves the end of the air ring that is blown back to the upper surface of the needle plate between the needle and the knife for cutting the fabric end toward the air ring holding device. It only needs to protrude upward, and it is only necessary to retract the cloth plate to the bottom of the cross plate at other times, so that the air valve does not interfere with the sewing, and the sewing fabric is placed along the top surface of the cross plate. It can proceed smoothly. In addition, there is no risk of clogging of the airflow injection hole formed on the side wall of the upper end of the air valve, which may interfere with the transition function of the end of the air ring due to the auxiliary air flow. The movement processing operation can always be performed reliably and stably.

  Further, as the suction pipe of the idle ring cutting device in the idle ring stitching device of the sewing machine according to the present invention, the tip side surface portion is normally moved and held at a position where the suction port of the suction pipe is enlarged. When the airflow is blown out from the blowout port, the air ring that is blown back by the blown airflow moves along the upper surface of the needle plate between the needle and the knife for cutting the fabric end and moves toward the front side of the needle drop part. It is preferable to use one provided with a movable plate-like cover member that is moved to a position to be guided.

  In this case, the movable plate-shaped cover member is moved to the rear side of the needle drop portion when the empty ring formed continuously with the stitch forming claw portion of the needle plate is sucked into the suction pipe of the empty ring cutting device. Since the suction port at the tip of the pipe is large, the empty ring can be reliably sucked into the suction pipe without mistake and cut at a predetermined length. Since the movable plate-shaped cover member moves to the front side and guides the air ring toward the front side of the needle drop portion, the air ring is blown back as straight as possible to move the needle. Can be reliably and stably positioned in a narrow portion such as between the fabric edge cutting knife.

  In addition, as a suction pipe of the empty ring cutting device in the empty ring stitching device of the sewing machine according to the present invention, the suction side pipe portion is overlapped with a part of the distal end portion of the stitch forming claw portion of the needle plate. An extended plate-shaped cover member is fixed, and an annular guide hole having a narrow vertical width and a vertical width are formed at the front end portion of the fixed plate-shaped cover member with a substantially same height as the upper surface of the needle plate as a lower edge. It is more preferable to use the one having a wide empty ring suction port formed continuously before and after the sewing progressing direction.

  In this case, when sucking the empty ring formed continuously with the stitch forming claw portion of the needle plate into the suction pipe of the empty ring cutting device, the wide empty ring suction formed at the distal end portion of the fixed plate-like cover member When the empty ring is blown back from the suction pipe toward the needle drop part while the empty ring can be surely sucked into the suction pipe through the mouth and cut at a predetermined length, the claw part for stitch formation of the needle plate It will be guided to the position just above. Therefore, the blown-back empty ring is blown upward from the upper surface of the needle plate, and there is no risk of entanglement with the nail portion on the lower side of the presser foot that is lifted from the upper surface of the needle plate immediately before the blow-back and is separated. It can be reliably and smoothly blown back along the upper surface of the narrow needle plate such as between the scalpel. Further, since the cover member only has to be fixed to the suction pipe of the idle ring cutting device, the structure can be simplified and the cost can be reduced compared to the case where a movable plate-like cover member is employed.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is an overall schematic perspective view of a two-needle edge stitching machine with an empty ring stitching device according to the present invention, and FIGS. 2 and 3 are perspective views showing the configuration of the main part of the empty ring stitching device. . In the empty ring stitching device according to the present invention, the same components as those in the conventional empty ring stitching device shown in FIGS. 11 to 13 are denoted by the same reference numerals, and description thereof is omitted or simplified. To do.

  In FIG. 1, reference numeral 1 denotes a cross plate of an edge stitch sewing machine M. A needle plate 13 having a needle drop portion 14 and a seam forming claw portion 13a (see FIG. 2) is fixed to a predetermined position of the cross plate 1. A cloth edge cutting knife 2 for cutting and aligning the edges of the sewing cloth at the front part near the base end of the seam forming claw part 13a (only the movable upper knife part is shown in FIGS. Are omitted). In addition to the presser foot 3, a needle bar supported by the sewing machine bed portion 4 and two needles that can be reciprocated up and down with respect to the needle drop portion 14 via a needle stopper are provided above the needle plate 13. 15 and a photoelectric fabric sensor (not shown because it is well known) that allows the sewing machine M to rotate when the sewing fabric is present (dark state) by detecting the presence or absence of the sewing fabric on the upper surface of the needle plate 13. In addition, an empty ring cutting device 10 to be described later is disposed on the rear right side of the sewing traveling direction X with respect to the needle plate 13, and empty on the right side of the needle plate 13 on the front side of the needle drop portion 14. An annular holding device 16 is provided, and an auxiliary airflow (hereinafter referred to as auxiliary airflow) jetting device 5 is provided on the cross plate 1 portion near the left side of the needle plate 13 on the front side of the needle drop portion 14. Yes.

  As shown in FIGS. 1, 2, and 3, the empty ring cutting device 10 includes an empty ring 12 (see FIG. 3) that is continuous with the stitch forming claw portion 13 a of the needle plate 13 at the end of sewing of the preceding sewing material. ) Is sucked into the suction pipe 11 from the suction port 11a at the tip of the suction pipe 11 connected to an air source such as a vacuum pump (not shown) via a venturi pipe (not shown) and a hose 6. 12 is cut from the sewing fabric by an upper knife (not shown) attached to the tip of the suction pipe 11 and a lower knife 7 which moves up and down via a drive mechanism (not shown), and then the cut ring 12 is cut off. Blow back to the suction port 11 a side by the reverse air flow generated in the suction pipe 11, and then connect to the air source and be fixed and held along the right side surface of the suction pipe 11. Sewing from A needle drop portion along the upper surface portion of the needle plate between the right needle of the two needles 15 and the knife 2 for cutting the fabric end by an air flow blown in a substantially linear shape in the direction Y opposite to the row direction X It is comprised so that it may blow back to 14 near side.

  On the left side surface of the tip of the suction pipe 11 of the idle ring cutting device 10, it is possible to reciprocally slide in the direction of the arrow xy within a certain range along the sewing progress direction X via the long hole 9 and the bolt-shaped guide 19. A movable plate-like cover member 20 is attached. The movable plate-shaped cover member 20 is normally formed by a biasing force of a spring 21 stretched between a protruding piece 11b fixed to the suction pipe 11 side and a protruding piece 20a fixed to the plate-shaped cover member 20 side. The suction port 11a at the tip of the suction pipe 11 is moved and held at a position where the suction port 11 is greatly opened, and when the air flow is blown out from the tip outlet port 8a of the air pipe 8, the biasing force of the spring 21 is accompanied by the extension operation of the air cylinder 22. The needle 12 is moved along the upper surface of the needle plate between the right needle of the two needles 15 and the scalpel 2 for cutting the fabric end, and the idler ring 12 is slid in the y direction and moved back by the air flow. It is configured to guide the movement toward the front side of the drop portion 14.

  Further, as clearly shown in FIGS. 4 to 6, the auxiliary air flow ejection device 5 has a circular opening in the cross plate 1 that is substantially flush with the needle plate 13 near the left side surface portion of the needle plate 13. A valve holder 24, which is disposed flush with the upper surface of the cross plate 1 and in which an air chamber 23 is formed below, is fitted in the opening 1a. The valve holder 24 is fixed to a bracket 26 secured to the cross plate 1 by bolts 25 at a mounting portion 24b extending along the lower side of the cross plate 1 via bolts 27. A cylindrical cap-shaped air valve 28 having a circular opening 24a communicating with the air chamber 23 and having a lower end opened and an auxiliary air flow ejection hole 28a formed on the upper end side wall is formed in the opening 24a. It is impossible to rotate and can be raised and lowered via a guide groove 23a recessed in the inner peripheral wall portion of the air chamber 23 so that a guide protrusion 28c protruding radially outward from a flange 28b formed on the outer peripheral edge of the lower end is engaged. It is fitted and held (movable up and down).

  An air supply passage formed in the bracket 26 is communicated with a pressurized air supply pipe 29 as a means for introducing a pressurized air flow into the air valve 28 at a lower end opening portion of the air valve 28. 26a is open-connected, and a compression spring 30 for biasing the air valve 28 in the downward direction is interposed between the upper wall of the air chamber 23 and the lower end flange 28b of the air valve 28. As shown in FIG. 4, the air valve 28 is urged by the urging force of the compression spring 30 so that the auxiliary air flow ejection hole 28a is retracted below the cross plate 1, and the pipe 29 and By introducing pressurized air into the air valve 28 through the air supply passage 26a, the auxiliary air flow ejection hole 28a protrudes upward from the cross plate 1 as shown in FIG. Closing auxiliary air flow Jets crossing diagonally forward from the rear left side position in the sewing progress direction X with respect to the movement trajectory of the air ring 12 blown back to the front side of the needle drop portion 14 along the upper surfaces of the plate 1 and the needle plate 13. It can be switched to a state.

  Further, the empty ring holding device 16 includes a pair of holding members 16a and 16b that can be opened and closed with respect to each other, and these pair of holding members 16a and 16b are arranged around a fulcrum shaft 32 via a cylinder 31 in FIG. By moving to the right in a state where the end of the ring 12 is clamped at a position where it can be driven and swung in the direction c-o and is swung in the direction of the arrow o, the ring 12 is cut by the knife 2 for cutting the material end. It is configured to be guided by a section and cut.

  Next, a description will be given of an empty ring stitching operation by the edge overlock sewing machine with the empty ring stitching device configured as described above.

  When the sewing end of the preceding sewing fabric passes the fabric sensor (not shown) and the sensor becomes non-detected (bright state), the suction pipe 11 of the idle ring cutting device 10 starts to suck and the needle plate 13 The empty ring 12 formed continuously with the seam forming claw portion 13a is sucked into the suction pipe 11 from the suction port 11a, and the sucked empty ring 12 moves up and down with respect to the upper knife (not shown). The lower knife 7 cuts from the sewing fabric. Thereafter, the presser foot 3 rises away from the upper surface of the needle plate 13 and is blown back to the suction port 11 a side by the reverse air flow generated in the suction pipe 11. Subsequently, the blown-back air ring 12 is moved from the tip blowing portion 8a of the air pipe 8 to the right needle and the fabric end of the two needles 15 by the air flow blown in the direction Y opposite to the sewing progress direction X. Along the upper surface of the needle plate 13 between the cutting knife 2 and the needle drop portion 14, it is blown back substantially linearly.

  Immediately after that, the air valve 28 in the auxiliary air flow ejection device 5 that has been retracted below the cross plate 1 is supplied by pressurized air introduced into the air valve 28 through the pipe 29 and the air supply passage 26a. As shown in FIG. 5, the auxiliary air flow ejection hole 28 a protrudes upward from the cross plate 1, and the auxiliary air flow ejected from the projected auxiliary air flow ejection hole 28 a is the needle drop portion 14. As shown by a thick arrow B in FIG. 3, the hollow ring 12 is blown back to the near side of the sewing ring X and blown diagonally forward from the rear left side position in the sewing progress direction X. The end portion is moved to the side of the empty ring holding device 16 and is sandwiched between the pair of clamping members 16a and 16b, and the preparation for the next sewing is completed.

  Next, the succeeding sewing fabric 18 (see FIG. 8) is set on the needle plate 13 so that the front edge 18e at the sewing start end is positioned substantially on the same line as the knife 7 for cutting the fabric edge in the sewing progress direction X. When the cloth sensor detects it (dark state), the presser foot 3 is lowered so as to contact the upper surface of the needle plate 13, and the next sewing can be started. In this state, when the pedal is turned on, The sewing machine M starts to rotate and the subsequent sewing fabric 18 is fed in the sewing progress direction X until the sewing start end front edge 18e reaches the needle drop portion 14 of the needle plate 13. During this time, the empty ring 12 wound around the stitch forming claw portion 13a of the needle plate 13 remains wound around the claw portion 13a.

  Further, the subsequent sewing fabric 18 is fed in the sewing progress direction X, and the sewing start end front edge 18e exceeds the tip of the stitch forming claw portion 13a of the needle plate 13 from the sewing start end front edge to the fabric edge. When the dimension to the cutting knife 2 reaches a predetermined length, the pair of holding members 16a and 16b of the empty ring holding device 16 cuts the dough edge cutting knife 2 with the empty ring 12 held between them. Move right towards the club.

  Then, the empty ring 12 guided to the cutting portion of the cloth edge cutting knife 2 is cut by the knife 2 together with the side edge portion of the sewing cloth 18, and the cut empty ring portion is the sewing start end of the subsequent sewing cloth 18. It is drawn into the seam 19 of the part and sewn.

  In the above-described empty ring stitching operation, according to the above-described embodiment, after being formed continuously with the seam forming claw portion 13a of the needle plate 13, it is sucked into the suction pipe 11 of the idle ring cutting device 10. The air ring 12 cut in this manner is blown back along the upper surface of the needle plate 13 between the needle 15 and the cloth edge cutting knife 2 by the air flow, and the end of the air ring 12 that has been blown back is moved. The part is moved toward the empty ring holding device 16 on the front side of the needle drop portion 14 by the auxiliary air flow injected from the injection hole 28a of the auxiliary air flow injection device 5, and is held (clamped) by the empty ring holding device 16. As described above, the empty ring 12 is blown back in the direction opposite to the sewing progress direction from the suction / cutting of the empty ring 12, and the movement of the empty ring from the end of the empty ring toward the empty ring holding device 16 is retained. All through air flow From the installation of air-ring suction nozzle or the like of the movable was conventionally used is not required, with attained is simplified in structure, it is possible to improve the workability by eliminating disturbing and blind sewing operation.

  In addition, finally, as shown in FIG. 7, the empty ring 12 can be held by the empty ring holding device 16 through the right side of the two needles 15 without causing any interference with the needle thread 17. Therefore, it is possible to reliably avoid the occurrence of the situation in which the needle 15 passes through the empty ring 12 during the next sewing. Therefore, as shown in FIG. 8, the empty ring 12 is started to be sewn on the next sewing fabric 18. Occurrence of a sewing failure such as a reliable and smooth sewing into the end seam 19 and a part of the empty ring projecting and remaining on the front edge 18e of the end of the sewing fabric 18 as a dumpling. It can be surely prevented.

  Further, as in the above embodiment, a movable plate-like cover member 20 is attached to the tip side surface portion of the suction pipe 11 of the idle ring cutting device 10, and this movable plate-like cover member 20 is attached to the needle plate 13. When the hollow ring 12 formed continuously with the seam forming claw portion 13a is sucked into the suction pipe 11, it is moved to the rear side of the needle drop part 14 to secure a large suction port 11a at the tip of the suction pipe 11. The air ring 12 is surely sucked into the suction pipe 11 without any mistake and can be cut at a predetermined length, while the air ring 12 is blown back to the suction port 11a side of the suction pipe 11 by the reverse air flow. 12 is moved back by the air flow blown from the tip blowout portion 8a of the air pipe 8, the movable plate-like cover member 20 is slid in the direction approaching the needle drop portion 14 (y direction). Therefore, the empty ring 12 can be blown back and guided as straight as possible, and the empty ring 12 can be reliably and stably held in a narrow portion such as between the needle 15 and the knife for cutting the fabric end 2. it can.

  In the above embodiment, the description has been made with the movable plate-like cover member 20 attached to the left side surface at the tip of the suction pipe 11 of the idle ring cutting device 10, but instead of this, FIG. 9 and FIG. As shown in FIG. 4, a fixed plate-like cover member 33 may be attached to the left side surface portion at the tip of the suction pipe 11.

  The fixed plate-shaped cover member 33 is extended until the tip end portion 33a overlaps with a part of the tip end portion of the stitch forming claw portion 13a of the needle plate 13, and the extended tip portion 33a is extended. In addition, the narrow annular guide hole 34a having a narrow vertical width and the wide annular suction port 34b having a wide vertical width are arranged at the front and rear in the sewing progress direction with their lower end edges 34e positioned at substantially the same height as the upper surface of the needle plate 13. A long and narrow hole 34c is formed at the upper end of the rear end of the hollow ring suction port 34b having a wide vertical width and guides the sucked hollow ring to the cutting portion between the upper knife and the lower knife 7. Is formed. The fixed plate-shaped cover member 33 is configured to be adjustable in position before and after the sewing progress direction through the long holes 35 and the bolts 36. This is because the initial mounting position of the plate-shaped cover member 33 is finely adjusted. This is for adjustment, and is used in a fixed position without moving at all during the idle stitching operation.

  When such a fixed plate-like cover member 33 is used, it is fixed when the empty ring 12 formed continuously with the seam forming claw portion 13a of the needle plate 13 is sucked into the suction pipe 11 of the empty ring cutting device 10. The air ring 12 can be surely and smoothly sucked into the suction pipe 11 through the wide air ring suction port 34b formed in the front end portion 33a of the plate-like cover member 33, and can be cut at a predetermined length. However, when blowing back from the suction pipe 11 toward the needle drop portion 14, it is possible to guide the empty ring 12 to a position directly above the stitch forming claw portion 13 a of the needle plate 13. Therefore, there is no possibility that the blown-back empty ring 12 is blown upward from the upper surface of the needle plate 13 and entangled with the claw portion on the lower surface side of the presser foot 3 which is lifted from the upper surface of the needle plate 13 and is separated immediately before blowing back. 15 and the cloth edge cutting knife 2 can be reliably and smoothly blown back along the narrow upper surface of the needle plate 13. Further, since the cover member 33 only needs to be fixed to the suction pipe 11 of the idle ring cutting device 10, it is easy to construct with a simple structure and at a lower cost than when a movable plate-shaped cover member is employed.

  Further, as described in the above embodiment, the auxiliary air flow ejection device 5 can be switched between a state of protruding upward and a state of retreating downward through the opening 1a formed in the cross plate 1, and its upper end portion. By using a cylindrical cap-shaped air valve 28 having an auxiliary air flow ejection hole 28a formed on the side wall, the air valve 28 may be retracted below the cross plate 1 during normal sewing. The valve 28 does not obstruct the sewing, and the sewing fabric can be smoothly advanced along the upper surface of the cross plate 1, and the air flow ejection hole 28a is clogged with chips, etc. There is no risk of hindering the movement function of the end of the air ring due to the air ring, and the air ring movement processing action by the auxiliary air flow can always be performed reliably and stably even during long-term use. However, instead of this, as can be seen in Patent Documents 2 and 3, the auxiliary air flow is provided with a fixed air pipe nozzle that ejects an auxiliary air flow on the left side of the needle drop portion on the cross plate. An ejection device may be used.

  Furthermore, although the two-needle edge stitching machine M is illustrated in the above embodiment, the same effects as described above can be obtained even when applied to a multi-needle edge stitching machine other than the two needles. Is.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an overall schematic perspective view of a two-needle edge stitching machine with an empty ring stitching device according to an embodiment of the present invention. It is a perspective view which shows the structure of the principal part of an empty ring stitching apparatus same as the above. It is a perspective view which shows the structure and operation | movement of the principal part of an empty ring stitching apparatus same as the above. It is a longitudinal cross-sectional view of the principal part which shows the structure of the auxiliary | assistant airflow ejection apparatus in an empty ring stitching apparatus same as the above. It is an expanded longitudinal cross-sectional view of the principal part explaining operation | movement of an auxiliary airflow ejection apparatus same as the above. It is a top view of the air valve which is a component of an auxiliary airflow ejection apparatus same as the above. It is a perspective view of the principal part which shows the state at the time of completion | finish of the empty ring movement effect | action by an empty ring stitching device same as the above. It is a perspective view which shows the sewing product after empty ring sewing. It is an expansion perspective view of the principal part of the 2 needle | hook edge stitching sewing machine with an empty ring stitching apparatus which concerns on other embodiment of this invention. It is a side view of the principal part which shows the structure of the empty ring cutting device in an empty ring stitching device same as the above. It is a perspective view which shows the structure and operation | movement of the principal part of the conventional empty ring stitching apparatus. It is a perspective view of the principal part which shows the state at the time of completion | finish of the idle ring movement effect | action by the conventional idle ring stitching apparatus. It is a perspective view which shows the sewing product after empty ring stitching by the conventional blank ring stitching apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Cross plate 1a Opening 2 Knife for cutting | disconnecting material | dough end 5 Auxiliary air flow ejection device 8a Air flow blower outlet part 10 Empty ring cutting device 11 Suction pipe 11a Suction port 12 Empty ring 13 Needle plate 13a Stitch formation claw part 14 Needle drop part DESCRIPTION OF SYMBOLS 15 Needle 16 Empty ring holding | maintenance apparatus 18 Sewing cloth 19 Seam 20 Movable plate-shaped cover member 28 Air valve 28a Auxiliary air flow ejection hole 29 Pressurized air supply pipe (auxiliary air introduction means)
33 Fixed plate-shaped cover member 34a Empty ring guide hole 34b Empty ring suction port X Sewing progress direction Y Reverse direction of sewing progress direction

Claims (6)

The sewing material is drawn by sucking the idle ring formed at the stitch forming claw part of the needle plate at the end of sewing of the sewing material into the suction pipe of the idle ring cutting device provided on the rear side in the sewing progress direction from the needle drop part. The end of the cut ring is blown back to the front side of the needle drop portion by an air current blown in the direction opposite to the sewing progress direction, and the end of the ring that has been moved back is moved. When the sewing machine starts holding the next sewing fabric, the sewing machine pulls it into the stitches at the sewing start end of the sewing fabric and holds the sewing machine. A method,
The end of the idle ring cut by being sucked into the suction pipe of the idle ring cutting device is provided at the front part near the proximal end of the needle that moves up and down with respect to the needle drop part and the seam forming claw part. The edge of the empty ring that has been blown back is moved back along the upper side of the needle plate between the knife for cutting the fabric edge and aligning the edges of the sewing fabric. It is moved to the holding position by the empty ring holding device and held by the auxiliary air current that is jetted crossing from the rear side position in the sewing progress direction to the diagonally front side with respect to the loop return movement trajectory. A sewing method for the sewing machine.   The auxiliary airflow can be switched between a state of projecting upward and a state of retracting downward of the cross plate through an opening formed in the cross plate substantially flush with the needle plate near the side of the needle plate. A cap-shaped air valve, an air flow introducing means for introducing a pressurized air flow into the air valve, and an upper end side wall of the air valve, and when the air valve protrudes above the cross plate An airflow ejection hole of an auxiliary airflow ejection device comprising an airflow ejection hole for ejecting a pressurized airflow introduced therein along the upper surface of the cross plate and the needle plate is ejected from the airflow ejection hole. 2. A sewing method for a circular ring of a sewing machine according to 1. At the end of sewing of the sewing fabric, the idle ring formed continuously with the stitch forming claw part of the needle plate is sucked into the suction pipe of the idle ring cutting device provided on the rear side in the sewing progress direction from the needle drop part and sewn. The end of the cut ring is blown back to the front side of the needle drop portion by an air flow blown in the direction opposite to the direction of sewing, and the end of the blown ring is blown back. Is held by an empty ring holding device provided on the front side of the needle drop portion, and is sewn by being pulled into the stitches at the sewing start end of the sewing fabric as the next sewing fabric starts sewing. The sewing machine has a sewing machine
The tip of the suction pipe of the idle ring cutting device has a needle that moves up and down the end of the idle ring that is sucked into the suction pipe and cut with respect to the needle drop part, and a base for the seam forming claw part. An air flow outlet is provided so as to blow back toward the front side of the needle drop portion along the upper surface of the needle plate between the knife for cutting the fabric edge and the knife for cutting the edge of the sewing fabric provided near the edge. And an end portion of an air ring which is blown back to the front side of the needle drop portion by a blowout airflow from the air outlet portion is provided on a side portion of the needle drop portion. An auxiliary airflow ejecting device is provided to eject the auxiliary airflow crossing diagonally forward from the rear side position in the sewing progress direction with respect to the rewinding movement trajectory of the air ring so as to move to the holding position by Sewing machine Real device.   The auxiliary airflow ejection device switches between a state of projecting upward and a state of retracting downward through an opening formed in a cross plate substantially flush with the needle plate near the side of the needle plate The cap-shaped air valve made possible, air flow introducing means for introducing a pressurized air flow into the air valve, and an upper end side wall of the air valve are formed on the upper side wall of the air valve, and the air valve protrudes above the cross plate. 4. The sewing machine according to claim 3, further comprising an air flow ejection hole for ejecting the pressurized air flow introduced therein along the upper surface of the cross plate and the needle plate. .   The tip side surface portion of the suction pipe of the air ring cutting device is normally moved and held at a position where the suction port of the suction pipe is enlarged, and is blown back by the blown airflow when the airflow blows out from the airflow outlet. A movable plate-shaped cover member that is moved along a needle plate upper surface portion between the needle and the knife for cutting the fabric edge to a position for moving and guiding the empty ring toward the front side of the needle drop portion. The sewing machine according to claim 3 or 4, which is provided.   A plate-like cover member extending to a position that overlaps a part of the tip of the stitch forming claw portion of the needle plate is fixed to the tip side surface portion of the suction pipe of the idle ring cutting device. At the front end portion of the fixed plate-like cover member, there are a hollow guide hole with a narrow vertical width and a hollow suction port with a wide vertical width at the front and rear in the sewing progress direction, with the bottom edge being substantially the same height as the upper surface of the needle plate. The sewing machine according to claim 3 or 4, wherein the sewing machine is formed continuously.

Images