TWI410544B - Box Machine Double Line Chain Stitch Sewing Machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a box-like bed double chain stitch sewing machine capable of nicely performing double stitching of a large-sized sewing cloth. <P>SOLUTION: In the box-like bed double chain stitch sewing machine provided with a box-like sewing machine bed 1 and a presser foot 5 for pressing the sewing cloth by descending on a needle plate 10 on the sewing machine bed 1, a knife mechanism is provided in the presser foot 5, and by making the upper face 20 of the sewing machine bed 1 on one side or both sides of the needle plate 10 lower than the upper face of the needle plate 10, a gap between the upper face 20 of the sewing machine bed 1 and the protrusion of the knife mechanism toward the outside of the presser foot 5 is secured. By an operator lending the hand utilizing this gap, the feeding of the sewing cloth can be assisted. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

Box machine double line chain stitch sewing machine

The present invention relates to a two-wire chain stitch (double loop stitch) sewing machine having a box-shaped sewing machine table.

The box-shaped machine double-chain chain stitch sewing machine is a form of industrial sewing machine. The sewing machine has a box-shaped sewing machine table having a flat upper surface on both sides of the needle plate. The flat upper surface of the sewing machine supports the sewing of the fabric on both sides of the needle plate, thereby reducing the labor for the operator to hold the cloth in the sewing. Therefore, the box-type machine double-line chain stitch sewing machine is very suitable for sewing large pieces of sewing fabric. A part of the box-shaped machine double-chain chain stitch sewing machine has a cylindrical shape with a flat upper surface on the outer end side than the needle plate. This type of sewing machine is called a two-wire chain stitch sewing machine for the middle cylinder type box machine.

As another form of industrial sewing machine, there is a curved wrist flat sewing machine. This sewing machine has a narrow cylindrical sewing machine table extending in one direction at a lower portion of the sewing frame, and a sewing machine arm extending in a direction different from the sewing machine table at the upper portion of the sewing frame. The curved wrist flat sewing machine is used, for example, for a joint of a lower portion of a crotch portion such as a brief or a shorts. This splicing is performed by overlapping the edges of the two pieces of fabric to be sewn up and down by a predetermined width, and feeding them to the needle board on the sewing machine table and down to the presser foot of the needle board.

The curved wrist-type flat sewing machine described in Japanese Laid-Open Patent Publication No. Hei 7-57272 (1995) has a special presser foot provided with a knife device. The presser foot has a pressure script body and two pressure claws. The script body is lowered on the needle plate, and the sewing cloth is held between the needle plate. The two jaws extend parallel to each other in front of the script body. The knife device includes a fixed knife (Fixed Knife) mounted on one side of the jaws and a movable knife (Movable Knife) mounted on the other side of the jaws. The fixed knife and the movable knife have a cutting edge at an end projecting between the two jaws. The cutting edge is opposed to each other before the needle drop position (the position where the needle is lowered).

The movable knife reciprocates by a transmission from the inside of the sewing machine arm, and is wiped with the fixed knife. The movable blade is mounted to partially protrude to the outside of the jaw, which is connected to a transmission mechanism from the inside of the sewing machine arm.

The operator puts the edge of the sewn fabric to be sewn together and feeds it between the two jaws while standing on the needle board. The edge of the sewn fabric is aligned to the wiping position of the fixed knife and the movable blade. Pressing the script body conveys the edges of the cut fabric up and down to the needle drop position. The operator using the sewing machine can perform the merging with a substantially constant stitch width without requiring manual work to adjust the overlap width.

This seam is also implemented in other forms of sewing machines. In the double-chain chain stitch sewing machine of the box-shaped machine, as described above, the sewing cloth can be stably supported on the sewing machine table. Therefore, the overlap width is adjusted in front of the needle plate by the manual work of the operator. Joint seam. Therefore, there is a problem that the completion state differs depending on the skill level of the operator.

This problem can be solved by installing a presser foot with a knife device provided in a curved wrist flat sewing machine. However, as described above, in order to support a large piece of sewn fabric, the sewing machine has a flat upper surface that spreads on both sides of the needle plate. The presser foot of the knife-equipped device provided in the curved wrist flat sewing machine has a movable knife projecting on one side of the presser foot as described above, and the projecting portion is connected to the transmission mechanism. Therefore, when the presser foot is applied to the double-chain chain stitch sewing machine of the box-shaped machine, the transmission mechanism of the movable knife operates near the upper surface of the box-shaped machine.

In the sewing operation, generally, the sewing fabric is pressed by hand in the vicinity of both sides of the presser foot, and is pressed in the conveying direction, thereby assisting the conveyance of the sewing fabric. This transfer assist is particularly important in the sewing operation of large sewn fabrics handled by the double-chain stitch sewing machine of the box-shaped machine.

Therefore, when the presser foot with the knife device is used in the double-chain chain stitch sewing machine of the box-shaped machine, one side of the presser foot, the transmission mechanism of the movable knife operates, and the other side of the presser foot, a part of the fixed knife protrudes Therefore, it is difficult to carry out the aforementioned transfer assistance, which may cause an obstacle to the sewing operation.

On the other hand, the operator can also use the curved wrist flat sewing machine to perform the joint of the large sewn fabric. However, the curved wrist flat sewing machine has a narrow-diameter cylindrical sewing machine table, and when the large-sized sewing cloth is joined, the sewing machine supports insufficient sewing cloth, and it is difficult to perform a good sewing operation.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a box-shaped machine double-chain chain stitch sewing machine having a presser foot with a knife device that cuts the edge of a cloth to be sewn, so that the operator's proficiency It is possible to implement a joint that is in good condition and does not hinder the transfer assisting work performed by the operator on both sides of the presser foot.

The box-shaped machine double-chain chain stitch sewing machine of the present invention comprises: a box-shaped sewing machine table having a flat upper surface for mounting a sewing cloth on both sides in the width direction of the needle plate, and a sewing machine above the sewing machine table a needle bar and a presser bar supported by the arm, a needle and a presser foot respectively mounted on the lower end of the needle bar and the press bar, and a conveying mechanism and a looper disposed inside the sewing machine table below the needle plate, the pressure The foot is lowered together with the pressing rod, pressed against the needle plate, and the conveying fabric is transported by the conveying mechanism in the longitudinal direction of the needle plate, and the needle is moved up and down together with the needle bar, and The fulcrum in which the conveying direction is parallel is centered on the curved needle that oscillates along the lower surface of the needle plate, wherein the presser foot further has a knife device having an upper surface along the needle plate in the conveying direction A movable knife that reciprocates in a cross direction, and a fixed knife that is wiped with the movable knife.

In the present invention, a press device having a fixed blade and a movable blade is provided in the presser foot for pressing the sewn fabric on the needle plate, so that the joint of the large sewn fabric can be performed with good quality without depending on the work. Proficiency of the person.

Further, the box-shaped machine double-chain chain stitch sewing machine according to the present invention is characterized in that the upper surface of the sewing machine table is configured to be lower than the needle plate on one side or both sides in the width direction of the needle plate. surface.

In the present invention, the upper surface of the box-shaped machine table is lower than the upper surface of the needle plate on one side or both sides of the needle plate, and the upper surface of the box-shaped machine table and the protruding portion of the movable knife protruding to the outside of the presser foot are ensured. The gap between them. The operator can use the slit to assist the conveyance of the sewn fabric by hand in the vicinity of the presser foot, so that the joint of the large sewn fabric can be satisfactorily performed.

Further, the box-shaped machine double-chain chain stitch sewing machine according to the present invention is characterized in that the upper surface of the sewing machine table and the upper surface of the needle plate are separated from the curved needle on both sides of the needle plate. The step portions provided by the interference between the swing regions are continuous.

In the present invention, the upper surface of the needle plate and the upper surface of the box-shaped machine are smoothly continuous by the step portion. Since the stepped portion is provided to avoid the swinging region of the looper, the operation of the looper performed inside the box-shaped machine is not hindered, and the large-sized sewing fabric can be stably supported, and the joint is performed.

Further, the box-shaped machine double-chain chain stitch sewing machine according to the present invention includes: a blade vibration shaft provided inside the sewing machine arm, and transmitting the repeated rotation of the blade vibration shaft to the movable blade. The movable mechanism of the movable knife for reciprocating motion.

In the present invention, the repeated rotation of the blade shaft inside the sewing machine arm is transmitted to the movable blade through the transmission mechanism. The movable knife provided in the presser foot can reliably reciprocate, and the edges of the sewn fabric are cut to achieve a good joint.

Further, the box-shaped machine double-chain chain stitch sewing machine according to the present invention is characterized in that the transmission mechanism includes a drive cylinder that penetrates and supports the lower portion of the sewing machine arm in the up-and-down direction, and the in-line retaining and supporting the pressure a support bushing at a lower portion of the lever; and a transmission connecting member that transmits the repeated rotation of the blade shaft to an upper portion of the drive cylinder located inside the sewing machine arm, at a lower portion of the drive cylinder that protrudes outside the sewing machine arm, A mount for the above movable knife is provided.

In the present invention, the repetitive rotation of the blade vibration shaft is transmitted to the transmission mechanism of the movable blade, and the transmission cylinder which also serves as the support member of the pressure bar can realize the external operation of the sewing machine arm from the axial direction of the sewing machine arm by a simple structure. The drive of the movable knife.

The objects and innovative features of the present invention will become more apparent from the written description of the appended claims.

Embodiments of the present invention will be described in detail below with reference to the drawings. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a perspective view showing the appearance of a double-chain chain stitch sewing machine for a box-shaped machine of the present invention. The "up, down, left, and right" used in the following description are "up, down, left, and right" in Fig. 1. In the following description, the outer side of the paper surface of FIG. 1 is referred to as "front", and the inner side of the paper surface of FIG. 1 is referred to as "rear".

The box-shaped machine double-chain chain stitch sewing machine shown in Fig. 1 has a sewing machine table 1, a foot column 2, and a sewing machine arm 3. The sewing machine table 1 has a box shape and has a flat upper surface 20. The leg 2 is erected substantially vertically at the right end of the sewing machine table 1. The sewing machine arm 3 extends leftward from the upper end portion of the leg 2 and is parallel to the upper surface 20 of the sewing machine table 1. The needle end 30 and the pressure bar 31 are supported at the distal end portion of the sewing machine arm 3.

The inside of the sewing machine arm 3 supports a needle bar 30 that can move up and down. The needle bar 30 moves up and down in accordance with the operation of the needle bar driving mechanism (not shown) provided inside the sewing machine arm 3. The needle bar 30 projects downward from the sewing machine arm 3. At the projecting end of the needle bar 30, a plurality of needles 4, 4, ... are mounted by the needle holder 40. The plurality of needles 4, 4... ascend and descend with the up and down movement of the needle bar 30.

The press lever 31 projects below the sewing machine arm 3 in the rear direction of the needle bar 30, and the presser foot 5 is attached to the extended end portion of the press lever 31. The presser foot 5 has a structure to be described later. The press lever 31 is supported by the inside of the sewing machine arm 3 and is movable up and down. The presser bar 31 moves in the up and down direction by the operation of the operator, and the presser foot 5 ascends and descends as the presser bar 31 moves up and down.

In the upper surface 20 of the sewing machine table 1, a needle plate 10 is attached corresponding to the lowered positions of the needles 4, 4, ... and the presser foot 5. FIG. 2 is an explanatory view showing a state in which the needle plate 10 is mounted. As shown in FIG. 2, the needle plate 10 is a rectangular flat plate which is long in the front-rear direction, and is detachably mounted on the mounting table 11 by a plurality of (only two) fixing screws 10a, 10a, ... 11 is fixed to the sewing machine table 1. In the front edge of the needle plate 10, a rectangular notch portion 12 is formed at the center in the width direction (left-right direction).

In the needle plate mounting table 11, a recess 12a is provided at a position matching the notch portion 12 of the needle plate 10. The recess 12a is wider than the notch 12 and is engaged with the guide mounting piece 14. The bottom surface of the recessed portion 12a is provided with a screw hole, and the guide mounting piece 14 is fixed below the notch portion 12 by pressing the screw 15 screwed to the screw hole from the bottom to the bottom surface of the needle plate 10. The guide mounting piece 14 has two screw holes arranged in front and rear. The cloth guide 16 is fixed to the guide mounting piece 14 by the stopper screws 17, 17 which are respectively screwed to the above-mentioned screw holes. The cloth guide 16 is a flat member and is disposed to extend rearward from a fixed position of the set screws 17 and 17, and stands upright with respect to the upper surface at the center in the width direction of the upper surface of the needle plate 10.

The pinholes 10 are formed in the needle plate 10. The feed holes 13, 13 are narrow rectangular openings whose long sides are located in the front-rear direction, and are separated on the left and right sides of the needle plate 10, and are provided in each of two. The feed holes 13, 13 are provided to extend the feed teeth that move inside the sewing machine table 1. The feed tooth has a well-known structure, that is, an oblong motion in which the forward and backward movement and the up and down movement are combined by the movement of the conveying mechanism inside the sewing machine table 1. The feed tooth moves in the upward direction through the respective feed holes 13, 13, ... and then moves to the upper direction of the needle plate 10, and then moves downward to move forward, thus performing the repetitive motion. By this operation, intermittently intermittent conveyance is applied to the sewing cloth (not shown) on the needle board 10.

Figure 2 shows the presser foot 5 and the needles 4, 4... together. When the presser foot 5 is lowered by the downward movement of the presser bar 31, as shown in the drawing, it is superposed on the needle plate 10, and the sewing fabric is sandwiched between the needle plate 10. The presser foot 5 has a presser body 50 fixed to the lower end of the presser bar 31, and two press jaws 51, 52. The claws 51 and 52 extend in parallel to the front side on the left and right sides of the front portion of the script body 50. The pressure claws 51 and 52 are opposed to each other by an appropriate slit in front of the script body 50 to form an introduction passage for sewing the cloth.

The presser foot 5 as described above is equipped with a knife device including a fixed blade 6a and a movable blade 6b. The fixed blade 6a is a plate-shaped blade that is fixed to the left pressing jaw 51. The fixed blade 6a is inserted into and fixed in a rectangular holding hole 53 provided in the pressing claw 51. The root of the fixed knife 6a projecting outside the jaw 51 is shown in FIG. The fixed blade 6a is provided with a blade at an end projecting toward the inside of the introduction passage between the jaws 51, 52.

The movable blade 6b is inserted into the holding hole 54 provided in the right claw 52 to be held. The movable blade 6b is movable in the left-right direction by the guidance of the holding hole 54. The movable blade 6b is provided with a blade at an end projecting toward the inside of the introduction passage between the jaws 51, 52. The root of the movable blade 6b projects to the outside of the jaw 52 with an appropriate length, and is fixed to the holder 75 at the lower end of the mount 74. The mount 74 and the holder 75 constitute a part of the transmission mechanism 7 which will be described later. The movable blade 6b reciprocates in the left-right direction in accordance with the repeated rotation of the blade axis 9 (see FIG. 4) transmitted through the blade transmission mechanism 7. The blade at the end of the movable blade 6b that performs the reciprocating motion is wiped in contact with the blade of the fixed blade 6a in the introduction passage.

The needles 4, 4, ... are raised and lowered behind the left and right pressing jaws 51, 52. The lowered needles 4, 4 are passed from the pinholes (not shown) provided in the presser body 50 and the pinholes 10b and 10b (refer to FIG. 3) provided on the needle plate 10 to reach the sewing machine table 1. internal. Among the introduction passages between the jaws 51, 52, the two pieces of the sewn fabric are introduced in a state in which the edges are aligned and vertically erected on the needle board 10. The fixed blade 6a and the movable blade 6b are aligned with the edge of the sewing cloth that reaches the wiping position. The cut fabric is vertically overlapped by the action of the script body 50, and is conveyed to the lowered position of the needles 4, 4, ... and stitched.

The cloth guide 16 reaches the inside of the introduction passage between the jaws 51 and 52, and functions to maintain the upright posture of the sewing cloth in the introduction passage. By loosening the screw 15, the position of the cloth guide 16 can be adjusted together with the guide mounting piece 14. By adjusting the position of the cloth guide 16, the operator can adjust the introduction posture of the sewing cloth so that the cutting by the fixed blade 6a and the movable blade 6b can be performed satisfactorily.

By loosening the screw 15, it is also possible to remove the cloth guide 16 from the front side of the sewing machine table together with the guide mounting piece 14. The fabric guide 16 is removed when other seams are performed. The other joints are, for example, a joint in which only one of the two fabrics is cut by the fixed blade 6a and the movable blade 6b, and the seam is superimposed on the other fabric to be joined.

A guide plate 55 is attached to the upper surface of the presser foot 52 on the right side. The guide plate 55 is a flat plate that is vertically erected on the front portion of the right side pressing claw 52 and that extends obliquely toward the rear portion of the left side pressing claw 51. The front side of the guide sheet 55 is recessed and bent. The guide sheet 55 thus attached guides the cut piece of the sewn fabric removed by the cutting of the fixed blade 6a and the movable blade 6b, and is conveyed to the outside of the left pressing jaw 51.

As shown in FIG. 1, a suction pipe 56 is attached to the lower portion of the left end surface of the sewing machine arm 3 via a mounting bracket 57. The straw has a suction opening that opens to the left rear portion of the presser foot 5, and the cut piece of the sewing fabric conveyed by the guide sheet 55 is sucked into the suction port to be removed. The mounting bracket 57 of the suction pipe 56 is swingable around the pin 58 provided in the vertical direction of the rear portion, and the front portion is opened. By opening the mounting frame 57, the suction pipe 56 is moved to the standby position away from the presser foot 5. The suction pipe 56 that has moved to the standby position does not hinder the loading and unloading of the sewing cloth on the sewing machine table 1.

The sewing machine table 1 shown in Fig. 1 has a flat upper surface 20 on the left and right sides of the needle plate 10. In the present invention, the upper surface 20 of the sewing machine table 1 is lower than the upper surface of the needle plate 10. The right side of the mounting position of the needle plate 10 is provided with a step portion 21 that is inclined downward as it goes away from the needle plate 10. Further, as shown in FIG. 2, the needle plate 10 has tapered and chamfered portions 18, 18 on both sides in the width direction. The chamfered portion 18 on the right side is continuous with the step portion 21 when it is mounted in the sewing machine table 1. The upper surface 20 of the sewing machine table 1 has a lower chamfered portion 18 and a height of the stepped portion 21 on the right side of the needle plate 10 than the upper surface of the needle plate 10, and is only chamfered on the left side of the needle plate 10 from the upper surface of the needle plate 10 The height of the portion 18.

3 is a front cross-sectional view of the sewing machine table 1 in the vicinity of the mounting position of the needle plate 10. Inside the sewing machine table 1, a looper 8 (Looper) is provided on the lower side of the needle plate 10. The looper 8 is attached to the end portion of the looper holder 81. The root of the looper base 81 is fixed to the looper shaft 80. The looper shaft 80 is stretched at a position away from the needle plate 10, and the axial length direction is located in the front-rear direction, and is repeatedly rotated within a predetermined angle range by a transmission from a sewing machine main shaft (not shown). With the repeated rotation of the looper shaft 80, the looper holder 81 and the looper 8 swing between the position indicated by the solid line in the figure and the position indicated by the broken line centering on the looper shaft 80.

The looper 8 thus oscillated is traversed on the lower surface of the needle plate 10 in synchronization with the ascending and descending of the needles 4, 4, ..., and is held by the needles 4, 4, which are lowered by the passage of the needle holes 10a, 10a, ... Needlework. The needle thread caught by the looper 8 is integrated with the looper thread held by the looper 8, and a line step is formed on the stitching fabric on the needle board 10. The swinging of the looper 8 is at the apex of the center portion of the needle plate 10 which is lowered by the needles 4, 4, ..., and is away from the needle plate 10 on the left and right sides. The step portion 21 of the sewing machine table 1 is provided to avoid interference with the swing region of the looper 8.

In Fig. 3, the right side of the needle plate 10 is provided with a step portion 21, and the upper surface 20 of the sewing machine table 1 on the same side is sufficiently lower than the upper surface of the needle plate 10 to ensure the presence of H in the figure with the upper surface of the needle plate 10. The difference between the heights indicated. The presser foot 5 is lowered to the upper surface of the aforementioned needle plate 10, and the sewing fabric is sandwiched between the presser foot 5 and the needle plate 10. The presser foot 5 has a knife device, and an end portion of the movable blade 6b held by the right presser foot 52 and a blade holder 75 connected to the end portion are located outside the presser foot 52 on the right side.

In the present invention, there is a height difference H between the upper surface of the needle plate 10 and the upper surface 20 of the sewing machine table 1, and a gap equal to or greater than the above-described height difference H is generated between the tool holder 75 and the upper surface 20 of the sewing machine table 1. Therefore, the operator presses the sewing fabric by the slit in the vicinity of the presser foot 5, and presses it back along the upper surface 20 of the sewing machine table 1, thereby assisting the conveyance of the sewing fabric.

As shown in Figs. 1 and 3, the upper surface 20 of the sewing machine table 1 is formed by a front cover 22 that is attached to the upper portion of the sewing machine table 1 that covers the right side of the needle plate 10 from the front side. As shown in FIG. 3, the stepped portion 21 is formed by bending an edge portion of the front cover 22.

The step portion 21 is also provided on the left side of the needle plate 10. By doing so, the operator can press the sewing cloth in the vicinity of the needle plate 10 on the left side of the presser foot 5, thereby assisting the conveyance of the sewing cloth without being disturbed by the presence of the fixed knife 6a protruding outside the pressure claw 51. . With such transfer assistance, the aforementioned merging can be satisfactorily performed.

The above effects can be achieved only by a simple structure in which the upper surface 20 of the sewing machine table 1 is disposed lower than the upper surface of the needle plate 10. The upper surface 20 of the sewing machine table 1 is only provided at a low level, and there is a flat portion which is extended on both sides of the needle plate 10, and the function of supporting the large-sized sewing fabric from below is maintained. Therefore, the double-line chain stitch sewing machine of the box-shaped machine of the present invention can suspend the edges of the large pieces of the sewn fabric with a certain width.

Fig. 4 is a perspective view of the transmission mechanism 7 of the movable blade 6b. 9 in Fig. 4 is the knife axis. The blade shaft 9 is supported inside the sewing machine arm 3, and is repeatedly rotated within a predetermined angle range by transmission from the sewing machine main shaft. One end portion of the blade shaft 9 is fixed with a swing arm 90 projecting outward in the radial direction. The swing arm 90 swings in accordance with the repeated rotation of the blade shaft 9.

The transmission mechanism 7 has a cylindrical drive cylinder 70. One end portion of the drive cylinder 70 in the axial length direction is thick, and the thicker portion has a cutter mounting arm 71 that protrudes outward in the radial direction. The other end of the drive cylinder 70 is mounted with a transmission arm 72 that projects outward in the radial direction. The drive cylinder 70 is supported by a support cylinder 73 that penetrates the lower arm of the sewing machine arm 3 so as to be movable downward from the side of the blade attachment arm 71, and is rotatable around the central axis.

The upper portion of the drive cylinder 70 projects toward the inside of the sewing machine arm 3. The transmission arm 72 is mounted on the extended end of the drive cylinder 70. The end of the transmission arm 72 is coupled to the swing arm 90 of the blade shaft 9 via a transmission link 91. The transmission link 91 transmits the oscillation of the swing arm 90 caused by the repeated rotation of the blade shaft 9 to the transmission arm 72. The transmission arm 72 swings in accordance with the swing of the swing arm 90, and the drive cylinder 70 having the swing arm 72 repeatedly rotates in an angular range corresponding to the repeated rotation of the blade shaft 9.

The transmission link 91 has a ball joint 92, 92 at the connection end of the swing arm 90 and the transmission arm 72. The ball joints 92, 92 absorb relative positional changes between the swing arm 90 and the drive arm 72 that rotate about different axes.

The blade mounting arm 71 provided at the lower end portion of the transmission cylinder 70 is located outside the sewing machine arm 3, and the distal end portion has a fixing seat 71a extending downward. A mounting seat 74 is fixed to the fixing base 71a, and a root portion of the movable blade 6b is attached to the tool holder 75 provided at a lower portion of the mounting seat 74 as described above. The movable blade 6b is held by the right pressing claw 52 of the presser foot 5, and is capable of reciprocating motion. The movable blade 6b is reciprocated by the swing of the blade mounting arm 71. The tool holder 75 is biased downward by a coil spring 76 provided in the mount 74. The coil spring 76 presses the movable blade 6b mounted in the blade holder 75 downward, and presses the inside of the introduction passage of the presser foot 5 onto the fixed blade 6a. The blade edge of the movable blade 6b that performs the reciprocating motion is wiped by the blade edge of the fixed blade 6a in a state of being pressed by the coil spring 76, and the edge of the sewing cloth is reliably cut.

In addition, in FIG. 4, in order to clearly show the attachment state of the movable blade 6b, the mounting direction of the movable blade 6b is different from the actual direction. The movable blade 6b is attached to extend in parallel with the blade axis 9, and reciprocates in the direction of the sewing machine arm 3 that supports the blade axis 9, that is, in the left-right direction.

A cylindrical support bushing 32 is inserted into the drive cylinder 70, and a press bar 31 is inserted through the support bushing 32. The lower end of the pressing rod 31 projects to the outside of the sewing machine arm 3, and the protruding end is mounted with the presser foot 5 as described above. The presser bar 31 moves in the up and down direction by sliding in the support bushing 32, and by this movement, the presser foot 5 rises and falls.

The blade drive mechanism 7 has a drive cylinder 70 that penetrates the lower portion of the sewing machine arm 3 in the vertical direction. The drive cylinder 70 is repeatedly rotated by the transmission from the blade shaft 9, and the movable blade 6b reciprocates as the drive cylinder 70 repeatedly rotates. A support bushing 32 is supported in the drive cylinder 70, and the support bushing 32 supports the presser bar 31 so as to be movable up and down. The drive cylinder 70 is coaxial with the presser bar 31 and passes through the sewing machine arm 3. The blade driving device 7 can realize the blade shaft 9 from the inside of the sewing machine arm 3 to the presser foot 5 provided outside the sewing machine arm 3 by the simple structure of the driving cylinder 70 which also serves as the supporting member of the pressing lever 31. The drive of the movable knife 6b.

Fig. 5 is an external perspective view showing another embodiment of the double-chain chain stitch sewing machine of the box-shaped machine of the present invention. The sewing machine shown in Fig. 5 is a two-wire chain stitch sewing machine of a middle cylinder type box machine, and has a sewing machine table 1, a foot column 2, and a sewing machine arm 3, like the sewing machine shown in Fig. 1. The needle end 30 and the pressure bar 31 are supported at the distal end portion of the sewing machine arm 3. Needles 4, 4 are attached to the lower end of the needle bar 30, and a presser foot 5 is attached to the lower end of the press bar 31. A needle plate 10 is disposed on the upper surface of the sewing machine table 1, and the needle plate 10 corresponds to the lowered positions of the needles 4, 4, ... and the presser foot 5.

The sewing machine table 1 has a different shape on the left and right sides of the needle plate 10 as shown in the drawing. The right side (root end side) of the needle plate 10 is a box-shaped portion 1a having a flat upper surface 20 extending rearward from the needle plate 10 by an appropriate length, whereas the left side (end side) of the needle plate 10 is A cylindrical portion 1b having a flat upper surface 20 within the length of the needle plate 10.

Both the box-shaped portion 1a and the upper surface 20 of the cylindrical portion 1b are lower than the upper surface of the needle plate 10. The upper surface 20 of the box-shaped portion 1a is continuous with the upper surface of the needle plate 10 by the chamfered portion 18 (see FIG. 2) of the right edge of the needle plate 10 and the stepped portion 21 which is inclined downwardly away from the needle plate 10. The upper surface 20 of the cylindrical portion 1b is continuous with the upper surface of the needle plate 10 by the chamfered portion 18 (refer to FIG. 2) of the left edge of the needle plate 10.

As shown in FIG. 2, the presser foot 5 has a presser body 50 attached to the lower end of the presser bar 31, and the pressurizing claws 51 and 52 extended forward from the press script body 50. The presser foot 5 is also equipped with a knife device including a fixed blade 6a and a movable blade 6b. The knife device is moved by the driving of the blade driving device 7 configured as shown in Fig. 4, and the edges of the sewing cloth introduced between the left and right jaws 51, 52 are aligned. The configuration and operation of the knife device and the blade driving device 7 are the same as those of the embodiment shown in Figs. 1 to 4, and detailed description thereof will be omitted.

In the embodiment shown in Fig. 5, the edge of the sewing fabric conveyed to the needle drop position is aligned by the movement of the blade device attached to the presser foot 5, so that a seam having a substantially constant stitch width can be realized. Further, since the upper surface 20 of the sewing machine table 1 is lower than the upper surface of the needle plate 10, the operator can press the sewing cloth by hand near the both sides of the needle plate 10 and the presser foot 5 to assist the conveyance of the sewing fabric, thereby enabling Reliably sew the large pieces of sewn fabric.

In the embodiment of Fig. 5, the cylindrical portion 1b is provided on the distal end side of the sewing machine table 1, and it is possible to cope with the sewing of the tubular cloth through which the cylindrical portion 1b can be inserted.

The embodiments described above are only intended to clarify the technical content of the present invention, and the present invention is not limited to the above-described embodiments and is interpreted in a narrow sense, and can be carried out within the scope of the technical idea of the present invention and the scope of the patent application. Various changes and implementation.

1. . . Sewing machine

2. . . Foot column

3. . . Sewing arm

4. . . Needle

5. . . Presser foot

6a. . . Fixed knife

6b. . . Movable knife

7. . . Transmission mechanism

9. . . Knife axis

10. . . Needle plate

10a. . . Stop screw

11. . . Mounting table

12. . . Notch

12a. . . Concave

13. . . Feeding hole

14. . . Boot installation

15. . . Loosen the screw

16. . . Cloth guiding

17. . . Stop screw

20. . . Upper surface

30. . . Needle bar

31. . . Pressure bar

40. . . Needle holder

50. . . Press script body

51, 52. . . Claw

53. . . Hold hole

54. . . Hold hole

55. . . Guide board

56. . . straw

57. . . Mount

58. . . pin

74. . . Mount

75. . . Tool holder

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a perspective view showing the appearance of a double-chain chain stitch sewing machine for a box-shaped machine according to the present invention.

Fig. 2 is an explanatory view showing a state in which the needle plate is mounted.

Figure 3 is a front cross-sectional view of the sewing machine table near the mounting position of the needle plate.

4 is a perspective view of a drive mechanism of the movable blade.

Fig. 5 is a perspective view showing the appearance of another embodiment of the double-chain chain stitch sewing machine of the box-shaped machine of the present invention.

1. . . Sewing machine

2. . . Foot column

3. . . Sewing arm

4. . . Needle

5. . . Presser foot

10. . . Needle plate

20. . . Upper surface

30. . . Needle bar

31. . . Pressure bar

40. . . Needle holder

56. . . straw

57. . . Mount

58. . . pin

Claims (4)

A box-shaped machine double-chain chain stitch sewing machine comprising: a box-shaped sewing machine table having a flat upper surface for loading a sewing cloth on both sides in the width direction of the needle plate, and a sewing machine arm above the sewing machine table a needle bar and a presser bar supported downwardly, a needle and a presser foot respectively mounted at a lower end of the needle bar and the press bar, and a conveying mechanism and a looper disposed inside the sewing machine table below the needle plate, the presser foot and the presser foot The pressure bar is lowered together and pressed onto the needle plate, and the sewing cloth for conveying the longitudinal direction of the needle plate is applied by the conveying mechanism, and the needle is moved up and down together with the needle bar, and the conveying direction is The parallel fulcrum is sewed by the curved needle centered on the lower surface of the needle plate, wherein the presser foot further has a knife device having a cross surface along the upper surface of the needle plate in the conveying direction a movable blade that reciprocates in a direction, and a fixed blade that is wiped with the movable blade; wherein an upper surface of the sewing machine table is configured to be one side or two in a width direction of the needle plate Lower than the upper surface of the needle plate. The double-chain chain stitch sewing machine of the box-shaped machine according to the first aspect of the invention, wherein the upper surface of the sewing machine table and the upper surface of the needle plate are avoided on the both sides of the needle plate. The step portion provided by the interference between the swinging regions of the looper is continuous. The double-chain chain stitch sewing machine of the box-shaped machine according to claim 1 or 2, further comprising: a knife shaft disposed inside the sewing machine arm; The transmission mechanism transmits the repeated rotation of the blade shaft to the movable blade to reciprocate the movable blade. The double-chain chain stitch sewing machine of the box-shaped machine according to the third aspect of the invention, wherein the transmission mechanism has a transmission cylinder that penetrates the lower portion of the sewing machine arm in the up-and-down direction and is supported, and is embedded and retained. a support bushing supporting a lower portion of the pressing rod; and a transmission connecting member transmitting the repeatedly rotating shaft shaft to the upper portion of the driving cylinder located inside the sewing machine arm, and the driving barrel protruding to the outside of the sewing machine arm The lower part is provided with a mount for the above movable knife.