TWI749282B - Sewing machine and method for closing open end of tubular knitted articles - Google Patents

Abstract

The present invention is concerned with a sewing machine and sewing method used thereof. The sewing machine is configured to knit and close an open end of a tubular knitted article, comprises a frame, a knitting head and a thread cutter. The knitting head and the thread cutter are disposed rotatablely on the frame, the knitting head having a needle, a needle-shaped hook and a knot making peg, to form thread knots, and the thread cutter is configured to cut the knitting thread, wherein the thread cutter is configured in a fashion that enables its movement relative to the knitting head.

Description

Sewing machine for sewing open ends of tubular knitted fabrics and its knitting method

The present invention relates to a method and a machine for stitching the opening edge of a fabric (such as a socks) manufactured into a tube or tube, especially a sewing machine and a knitting method using a pair of knitting needles.

Tubular knitwear (such as socks) is produced using circular knitting machines (cylindrical knitting machines). During production, both ends of the tubular knitwear have openings, and one end (toe cover) is moved from the knitting needle of the knitting machine to another station for knitting and sewing. The operation of moving the tubular knitwear to the toe bag stitching station can be performed manually or in an automated manner described in patent EP2377979.

As described in EP2377979, when the sock knitting cycle performed on the knitting machine is completed, the stitches in the last-to-knit rank will be received from the knitting needles, and the majority of the stitches in the last knit rank are divided into 2 Half of the braided rows (semi-rank), and move half of the braided rows and the other half of the braided rows to overlap each other correspondingly. This stacking operation is performed by a circular mechanism, which includes a pair of semicircular elements that can rotate 180 degrees, of which the semicircular element can swing on the other semicircular element, and at the same time all the coils are arranged along a semicircle and formed correspondingly Most pairs of stitches (pair of stitches). With the action of the circular mechanism, the pair of stitches are moved to the position where they are ready to be sewn, so as to sew one end of the tubular fabric (toe cover).

A knitting mechanism designed to sew toe covers may require one or two knitting needles. A knitting machine with a single needle is used to form one thread into a loop, and a knitting machine with two needles is used to form two threads. Knitting loop.

In the conventional technology, it is known that there are still defects when sewing the toe cover of the sock with a machine with a knitting needle, such as the risk of the knitting thread falling apart.

A knitting machine with two knitting needles basically includes a needle, a needle-shaped hook and a peg for knotting.

The knitting needles and crochet needles of the knitting machine are provided with holes at positions close to the edge of the tip for a knitting thread to pass through. When the knitting needle penetrates into the loop group, it moves into one side of the loop group and passes out on the other side, simultaneously pulling the knitting thread through the loop group. When the knitting needle and the knitting thread pass through the loop group, the knitting thread of the knitting needle will be retained by the crochet needle. The knitting needle is withdrawn from the last stitch that has been penetrated, and at the same time, the knitting thread remaining in the crochet needle is located in the stitch group. In this way, the coil assembly is knotted with a double knot.

The above operations will be repeated for each pair of stitches one by one until the toe cuff stitching step is completed. When the toe cover is stitched, there is no pair of stitches left on the knitting needles that can be knitted. Therefore, thread knots are placed on the knot making peg. The tip of the suture forming handle moves outwards, and has a conical shape where the knitting suture is placed. In this way, an extra thread knot is formed. In this position, one end of the extra knitting suture remains in the tubular knitwear (sock), while the other end is located at the suture forming handle, so it needs to be cut and released. When the extra knitting stitches are cut and released, part of the extra knitting stitches is left in the sock, and another part of the extra knitting stitches remains in the stitch forming handle. The additional knitting stitches remain in the part where the stitches form the handle, and are positioned next to the knitting start end of the toe cover of the continuation sock. Therefore, a predetermined length of knitting suture can be retained at the beginning and end of the knitting process of the toe cover of the sock by this method.

Ideally, the knitting stitches retained at the start and end of the toe cover of the sock should have an approximate length, generally between 8 and 10 millimeters (mm). On the other hand, in addition to the knitting stitches remaining at the beginning and end of the knitting process of the toe cover of the socks, after the knitting of the last knitting row of the socks, the knitting thread fragments of various lengths will also be left in the socks.

The conventional technology has many machines for cutting external knitting sutures and methods for such machines. As described in patent EP 2300653, the cutting knife is set on the sewing machine head to cut the knitting sutures at a predetermined distance, like a cutting knife. Form the distance between the shank and the suture. However, the machine described in patent EP 2300653 cannot cut the knitting stitches formed at both ends of the socks after knitting (almost standard length), and after knitting the last knitting row of the socks, it cannot cut the knitting left in the socks. Thread fragments (that is, woven thread fragments belonging to socks). Therefore, after the last knitting row of the sock is knitted, the strands of the knitting thread left in the sock are likely to have loose ends hanging arbitrarily in all directions.

In order to solve the foregoing deficiencies, the present invention provides a sewing machine for sewing an open end of a tubular knitted fabric, comprising a base, a sewing machine head, and a thread cutting device, a sewing machine head is pivotally connected to the base, and a thread cutting device Pivotally connected to the base, the sewing machine head has a knitting needle, a needle-shaped crochet needle, and a suture forming handle for forming a knitting suture, and the thread cutting device is used to cut the knitting suture, The wire cutting device can move relative to the sewing machine head.

According to the above arrangement, the sewing machine is provided with an air inlet controlled by the wire cutting device.

According to the above arrangement, the driving force for driving the thread cutting device to move relative to the sewing machine head is provided by the sewing machine head itself or by an independent actuator.

According to the above arrangement, no matter where the sewing head and the thread cutting device are located, the distance between the position where the knitting suture is formed and the thread cutting device varies between 3 to 30 millimeters (mm). Preferably, the The distance varies between 20 and 30 millimeters (mm).

The present invention also provides a knitting method for stitching the openings of a tubular knitted fabric, using the aforementioned sewing machine, and the steps include: forming the openings of the tubular knitted fabric into several pairs of stitch groups arranged along a semicircle, and introducing the sewing head of the sewing machine The knitting thread starts by knitting the paired loops to form a knitting suture; and after completing the knitting operation for all the paired loops, the sewing machine head forms an additional knitting suture, using a movable thread cutting device on the sewing machine The extra knitting thread is cut; wherein, the thread cutting device can move relative to the sewing machine head.

The present invention also provides a sock, which is produced using the aforementioned knitting method, and the sock contains 8 to 10 millimeters (mm) of knitting stitches at both ends for the knitting operation.

In this way, in addition to cutting the extra knitting suture, the thread cutting device can also be displaced relative to the sewing machine head to adjust the length of the knitting suture left on the tubular knitted fabric (sock) after cutting, and The length of the knitting thread left on the sewing machine head of the sewing machine is used as the start and end of the socks manufacturing process.

The embodiment provided by the present invention is a sewing machine including a base (10); a sewing machine head (20) is rotatably arranged on the base (10) and is pushed by a sewing machine head cam (11) of the base (10); The first motor (12), preferably a stepping motor, is arranged on the base (10), and the output end of the first motor (12) is provided with a crank (12a) and an arm (12b) connected, wherein One end of the arm (12b) is connected with the sewing machine head cam (11), so that the first motor (12) can drive the sewing machine head (20) to rotate with the rotating shaft (29) as the axis. In addition, the movement mechanism of the aforementioned sewing machine head (20) can also be provided by using a known linear mechanism.

One end of the cutting tool arm (30) is connected to the base (10), and the arm shaft (39) is used as the axis to rotate. Moreover, as shown in Figure 2, the first stopper (13) protrudes upward from the base (10) to block the sewing machine head (20) and position the sewing machine head (20) at the knitting position.

The other end (open end) of the cutting tool arm (30) is provided with a wire cutting device that can move along a circular path. The wire cutting device includes a fixed cutter (31) and a movable cutter (32) that can move closer to and away from the fixed cutter ( 31). The disc (32b) is arranged on the cutter, so that the movable cutter (32) can press the fixed cutter (31).

The second stopper (14) is arranged on the sewing machine head (20) and between the sewing machine head (20) and the cutting tool arm (30), and can be used to stop the cutting tool arm (30). In addition, the base (10) is also provided with a spring (15), the two ends of which are respectively connected to the base (10) and the cutting tool arm (30), and when the cutting tool arm (30) is unloaded, the cutting tool arm (30) is pushed toward the sewing machine The head (20) moves. As shown in Figure 10 (or Figure 11C), the sewing machine head (20) itself can rotate to a certain extent, but when the second gear (14) contacts the cutting tool arm (30), the sewing machine head (20) and the cutting tool arm ( 30) Will rotate together. Optionally, the second stopper (14) can be changed to the cutting tool arm (30).

Optionally, the driving mode of the cutting tool arm (30) and the wire cutting device may be an independent actuator separate from the driving of the sewing machine head (20). To this end, an additional motor element can be connected to the rotating arm shaft (39). However, it should be pointed out that the movement of driving the wire cutting device can be a linear mechanism or a mechanism that generates a general plane motion, and the wire cutting device moves along a linear path or moves on a plane. When the cutting tool arm (30) is driven by an independent actuator, the sewing machine head (20) can also be fixedly arranged on the base (10).

One end of the sewing machine head (20) is provided with a knitting needle (1), a needle-shaped crochet needle (2), and a suture forming handle (3) is arranged adjacent to the needle-shaped crochet needle (2), and the suture forming handle (3) is used for Place the knitted stitches that have been formed.

The knitting needles (1) and crochet needles (2) used for knitting operations are driven by a second motor (25), preferably a stepping motor. As shown in Figure 1, the output of the second motor (25) is provided with a first plate (21) and a second plate (22) connected, wherein one end of the first plate (21) is connected to the second motor ( 25), the other end of the first plate (21) is connected to the knitting needle control rod (23) in an eccentric rotation manner. The connection point between the knitting needle control rod (23) and the first plate (21) is also connected to one end of the second plate (22). The position of the second plate (22) close to the other end is connected with the crochet control rod (24) in an eccentric rotation manner.

The needle control lever (23) is embedded in the sewing machine head (20) with a swing bearing, the other end is fixed to drive the knitting needle (1), and the crochet control lever (24) is embedded in the sewing machine head with a swing bearing (20) On the body, the crochet needle (2) is fixed at the other end to drive its action. In this position, the power source is first transmitted to the gear set (28) with two gears that mesh with each other at 90 degrees, and then to the crochet needle (2). Therefore, when the second motor (25) completes one cycle, the knitting needle (1) and the crochet needle (2) will act in synchronization.

The cutting tool arm (30) is in the shape of a long arm, and includes two arm parts positioned with each other to form an obtuse angle. As mentioned above, the cutting tool arm (30) is rotatably connected to the base (10) via the arm shaft (39).

A supporting piston (35) is arranged at one end of the cutting tool arm (30) close to the wire cutting device, and the movable cutter (32) is driven by the piston rod (34) to actuate. The suction pipe (33) is arranged on the upper part of the cutting tool arm (30). The suction pipe (33) extends to the rear of the movable knife (32). When the movable cutter (32) is in the lower position

When the knitting operation progresses to the stage of sewing the opening of the tubular knitted fabric, as shown in Fig. 3, the paired loop sets (42) are arranged along the semicircle as described in the patent EP 2377979 and are stitched. At the same time, the knitting needles (1) and the crochet needles (2) used for knitting operations are positioned perpendicular to the horizontal knitting axis (41) of the paired stitch group (42), as shown in FIG. 3. At the same time, the cutting tool arm (30) is positioned adjacent to the track of the stitched coil group (42). In this position, the distance between the workstation where the knitting suture is formed and the position where the knitting suture will be cut by the thread cutting device is about 30 millimeters (mm).

As shown in Figure 4, when the knitting needle (1) is set on the sewing machine head (20), and the first pair of stitches (42) to be knitted are aligned with each other, the tip of the knitting needle (1) is aligned with each other. The knitting thread of the hole (1a) adjacent to the tip is passed through the paired loop group (42). Before the knitting needle (1) passes through the first set of stitches (42), the crochet needle (2) grabs the knitting thread passing through the knitting needle (1), and the knitting thread first passes through the hole (2a) at the tip of the crochet needle (2) ) Is pulled out, and the knitting needle (1) passes through the paired stitch group (42) and leaves the knitting thread in the paired stitch group (42). Therefore, the coil group (42) of the first pair is knitted and stitched together. When sewing the first paired stitch group (42), the knitting stitches (44b) that have been retained on the stitch forming handle (3) are also located on the first paired stitch group (42).

When the first pair of stitches (42) is knitted, the pair of stitches (42) carried by the semicircular element is rotated in a direction 43 around the weaving shaft (41) in a known manner. Thereby, the stitch group (42) of the second pair will be aligned with the knitting needle (1). The knitting operation is repeated in the knitting direction (5) (as shown in Fig. 12) to all the paired stitches to form the knitting suture (42a) to the stitch group (42). Next, the knitting suture (44b) is fixed to the first pair of stitch groups (42) and is advanced toward the cutter of the thread cutting device.

As shown in Fig. 5, the movable cutter (32) partially moves upward (32a) away from the fixed cutter (31), and therefore opens the air inlet (33a) of the suction pipe (33). The knitting stitches (44b) provided in the first stitch group (42) are drawn into the air inlet (33a) of the suction pipe (33). Next, the knitting suture (44b) fixed in the first stitch group is positioned between the fixed knife (31) and the movable knife (32).

As shown in Fig. 6, when the movable knife (32) moves downward (32a), the knitting suture (44b) is cut, and a segment with a length of about 8 to 10 millimeters (mm) is retained on the sock. Another segment of the knitted suture (44b) is sucked and processed by the suction pipe (33).

When the knitting operation of all the paired loop sets (42) is completed, additional knitting stitches (44) must be formed. Additional knitting stitches (44) are produced on the stitch forming handle (3), the tapered tip (3a) of the stitch forming handle (3) can move outward, and the stitch forming handle (3) has a tapered part for Place the knitted suture (4). Thereby, when an additional knitting stitch (44) with a length of 30 to 40 millimeters (mm) is formed, the sewing machine head (20) rotates partly along the direction (29a) with the shaft (29) as the axis, and then moves away from the stitch group (42). Under this action, the finally formed knitting suture (44) is positioned between the fixed knife (31) and the movable knife (32), and the knife is opened due to the upward movement of the movable knife (32). When in this position, the distance between the tip (3a) of the thread forming handle (3) and the cutter of the thread cutting device arranged on the sewing machine head (20) is about 20-30 millimeters (mm).

As shown in Figure 9, when the movable knife (32) moves down, the knitting suture is cut into two sections, one of which is about 8 to 10 millimeters (mm) left in the sock, and the length is about 20 to 30 millimeters (mm). The other segment of) remains in the suture forming handle (3).

As shown in Figure 10, when the toe bag is sewn and the knitting sutures (44a, 44b) are cut, the sewing machine head (20) rotates about 90 degrees along the direction (29aa) along its axis (29) as its axis. . At the same time, the cutting tool arm (30) will rotate along the direction (39a) with the arm shaft (39) as the axis, and will only partly rotate due to the setting of the second gear (14). The component is moved away.

The sewing machine provided in the foregoing embodiment can be used to sew the openings of the tubular knitted fabric, and the knitting method used is as follows. First, the sewing machine head (20) is located at the knitting position, the openings of the tubular knitted fabric form a loop group (42) arranged along a half circle, and the sewing machine head (20) introduces the knitting thread (4) to continue the original knitting suture (44b) Start weaving to form knitted stitches (42a). Next, open the air inlet (33a) of the suction pipe (33) to absorb the need to be cut The cut knitting suture (44b) is cut with a knife to cut the knitting suture (44b), and continue to knit to form a knitting suture (42a) to sew the connecting stitch group (42) until the knitting operation of all the stitch groups (42) is completed. Then the sewing machine head (20) is used to form additional knitting stitches (44), and the sewing machine head (20) is driven to partly rotate to deviate from the knitting position and approach the cutting tool arm (30), so that the extra knitting stitches (44) are Positioned between the fixed knife (31) and the movable knife (32), as shown in Figure 8 and Figure 11B, and use the knife to cut the extra knitting stitches (44) to divide into two knitting stitches (44a, 44b) . Finally, the sewing machine head (20) is driven to rotate completely and the cutting tool arm (30) is partially rotated to keep the cutting tool arm (30) away.

When sewing the opening of another tubular knitted fabric, repeat the steps in the previous section. Therefore, the present invention uses a wire cutting device that is independent of the sewing machine head. The knitting stitches formed at both ends of the tubular knitted fabric can be cut, and the length of the cut knitting stitches (that is, the distance between the thread cutting device and the stitch forming handle) can be adjusted.

1: Knitting needle

1a: Hole in the tip of the knitting needle

2: crochet

2a: The hole at the tip of the crochet hook

3: suture forming handle

3a: The suture forms the tip of the shank

4: weaving thread

5: Knitting direction

10: Base

11: Sewing machine head cam

12: The first motor

12a: double arm crank

12b: arm

13: First gear

14: Second gear

15: Spring

20: Sewing machine head

21: The first board

22: The second plate

23: Knitting needle lever

24: Crochet lever

25: second motor

28: Gear set

29: The shaft of the sewing machine head

29a: The direction of the sewing machine head away from the knitting position

29aa: The direction of the sewing machine head completely away from the knitting position

30: Cutting tool arm

31: Fixed tool

32: Movable knife

32a: Moving direction of active tool

32b: Disc

33: suction pipe

33a: air inlet

34: Piston rod

35: Piston

39: arm axis

39a: Cutting tool arm rotation direction

41: The weaving shaft of the suture group

42: coil group

42a: Knitting stitches of stitch group

43: direction

44: Uncut knit stitching

44a: The cut knitting stitches retained on the sock

44b: The part of the knitted stitch that remains on the stitch forming handle to be cut

Figure 1 shows a schematic diagram of the sewing machine

Figure 2 shows a schematic view of the sewing machine from another angle.

Figure 3 shows a top view of the sewing machine.

Figure 4 shows a schematic diagram of the sewing machine, showing an initial step.

Fig. 5 shows a schematic diagram of the sewing machine, showing the knitting process, in which the knitted suture part is sucked in by the suction pipe.

Fig. 6 is a schematic diagram of the sewing machine, showing that during the knitting operation, the unnecessary part of the knitting suture sucked by the suction pipe is cut.

Figure 7 shows a schematic diagram of the sewing machine, showing that after the knitting is completed, the sewing machine forms additional knitting stitches.

Fig. 8 is a schematic diagram of the sewing machine, showing that when the sewing machine head is far away from the knitting position to a certain extent, the extra knitting suture is caught by the thread cutting device in the open position.

Figure 9 shows a schematic diagram of the sewing machine, showing that the knitting thread is cut.

Figure 10 shows a schematic diagram of the sewing machine, showing that after the knitting operation is completed, the sewing machine head is retracted from the knitting position and rotated nearly 90 degrees.

Fig. 11A shows a schematic diagram of the sewing machine, showing that the sewing machine head is in the knitting position.

Fig. 11B shows a schematic diagram of the sewing machine, showing that the sewing machine head is partially withdrawn from the knitting position.

Fig. 11C shows a schematic diagram of the sewing machine, showing that the sewing machine head rotates approximately 90 degrees along the cutting tool arm from the knitting position.

Figure 12 shows a partial enlarged view of the knitting needles, needle-shaped crochet needles and suture forming handles on the sewing machine head of the sewing machine.

10‧‧‧Base

12‧‧‧First Motor

12a‧‧‧Double arm crank

12b‧‧‧arm

13‧‧‧First gear

20‧‧‧Sewing machine head

21‧‧‧First plate

22‧‧‧Second plate

23‧‧‧Knitting needle lever

24‧‧‧Crochet lever

29‧‧‧Rotating shaft of sewing machine head

29a‧‧‧The direction of the sewing machine head away from the knitting position

30‧‧‧Cutting Tool Arm

31‧‧‧Fixed tool

32‧‧‧movable knife

33‧‧‧Suction tube

35‧‧‧Piston

39‧‧‧Arm Shaft

41‧‧‧The bobbin of the suture group

42‧‧‧Coil Set

42a‧‧‧Knitting stitches for stitching loops

43‧‧‧direction

44a‧‧‧The cut knitting stitches reserved on the sock

44b‧‧‧The cut knitting stitch part remaining on the stitch forming handle

Claims (12)

A sewing machine for sewing an opening of a tubular knitted fabric includes a base, a sewing machine head, and a thread cutting device, the sewing machine head is connected to the base, the thread cutting device is movably connected to the base, and the sewing machine head has a knitting needle , A needle-shaped crochet needle and a suture forming handle are used to knit to form a knitting suture. The thread cutting device is used to cut the knitting suture. It is characterized in that: the thread cutting device is movable relative to the sewing machine head The thread cutting device is installed on a cutting tool arm, and the cutting tool arm is rotatably arranged on the base; after the knitting suture is cut, the sewing machine head rotates relative to the base to deviate from the knitting position, the thread cutting device Move along a circular trajectory. The sewing machine according to claim 1, wherein the thread cutting device is driven by the sewing machine head or is driven by an independent actuator, and moves along the circular track relative to the sewing machine head. The sewing machine according to claim 1, wherein the wire cutting device moves on a plane. The sewing machine according to claim 1, wherein a gear is provided between the cutting tool arm and the sewing machine head. The sewing machine according to claim 1, wherein the wire cutting device in the running state is connected with an air inlet. The sewing machine according to claim 5, wherein the wire cutting device has a fixed knife and a movable knife, and the air inlet hole is located behind the movable knife. The sewing machine according to claim 1, wherein the sewing machine head is driven by a sewing machine head cam on the base to rotate. The sewing machine according to any one of claims 1 to 7, wherein no matter where the sewing head and the thread cutting device are in any position, the distance between the forming position of the knitting suture and the thread cutting device The distance varies between 3 to 30 mm. The sewing machine according to claim 8, wherein the distance varies between 20 and 30 mm. A knitting method for stitching open ends of tubular knitted fabrics, using a sewing machine as described in claim 1, wherein the steps include: forming the openings of the tubular knitted fabric into a plurality of pairs of stitch groups arranged along a semicircle, and A sewing machine head of a sewing machine introduces a weaving thread and starts knitting the paired loops to form a knitting suture; and after completing the knitting operation for all the paired loops, the sewing machine head forms an additional knitting suture, and uses the A movable thread cutting device on the sewing machine cuts the extra knitting suture; wherein, the thread cutting device can move relative to the sewing machine head, the thread cutting device is installed on a cutting tool arm, and the cutting tool arm can be rotatably arranged On the base, after the knitting suture is cut, the sewing machine head rotates relative to the base to deviate from the knitting position, and the thread cutting device moves along a circular track. According to the knitting method described in claim 10, when the sewing machine head leaves another additional knitting suture to sew the opening section of another tubular knitted fabric, the sewing machine head is in the process of sewing the paired stitch groups , The thread cutting device is used to cut the other additional knitting thread. According to the knitting method described in claim 10, after the extra knitting stitches are cut, the length of the part of the knitting stitches left in the tubular knitted fabric is 8 to 10 mm, and the length of the part of the knitting stitches left in the head of the sewing machine is 8 to 10 mm. The length is 20 to 30 mm.

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