JPS63145696A - Yarn cutter of multirow double ring sewing machine - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention: Industrial Application Field This invention has a plurality of needles arranged in parallel in a direction perpendicular to the cloth feeding direction, and a double needle that moves reciprocatingly along the cloth feeding direction and cooperates with each needle. The present invention relates to a thread cutting device for a multi-row double chain stitch sewing machine, which includes a plurality of loopers that form chain stitches.

Conventional technology A multi-row double chainstitch sewing machine that is used exclusively for sewing bands or tapes onto fabrics, such as when sewing elastic bands around the waist of jigging pants, has a looper that runs in the fabric feed direction. There are two types: one type in which the looper reciprocates vertically along the cloth and multiple needles are lined up in a direction perpendicular to the cloth feed direction, and the other type in which the looper reciprocates horizontally and the needles are arranged diagonally in the direction of cloth feed. There is something. With the latter type, the stitches formed by each needle at the same time shift in the feed direction, whereas with the former type, the stitches formed at the same time do not deviate in the feed direction (this has the advantage that overlapping stitches at the end of the stitch can be finished beautifully). However, in conventional sewing machines of this type, the cutting of the needle thread and looper thread after sewing was done manually using scissors.

Problems to be Solved by the Invention This invention aims to improve work efficiency by installing a thread cutting device in the sewing machine described above, and using the thread cutting device to cut the thread, which was previously done manually. When installing a thread cutting device, it is necessary to ensure that it does not interfere with the movement of the looper, feed dog, etc. To do this, it must be installed on the side of the louver rather than behind the looper due to space considerations, and that it should be installed on the side of the louver rather than behind the looper due to space considerations. It is desirable that the length of the thread is short enough that the thread does not come out, and that there is no difference in the length of the remaining thread extending from each needle or looper.

An object of the present invention is to provide a thread cutting device installed in the above-mentioned sewing machine that satisfies these requirements.

According to the present invention, a plurality of hook-shaped scalpels are installed corresponding to each looper so as to be able to reciprocate between the upper side and the side of the looper, and the hook-shaped knife faces the looper. , a hook-shaped knife driving means that bends or bends near the louver and advances or retreats along a path along the looper; a receiving knife that is supported so as to be movable toward the looper; Relatedly, there is provided a thread cutting device having a receiver knife driving means for advancing the receiver knife toward the looper, and in which the hook-shaped knife cooperates with the receiver knife to cut the thread when the hook-shaped knife retreats.

The path that the hook-shaped scalpel follows is similar to a J-shape, and the hook-shaped knife drive means that moves the hook-shaped knife forward and backward along such a path uses a link mechanism, for example, a parallel link and a mechanism that moves the link back and forth. The actuation mechanism moves the parallel links together toward the looper and moves them forward, and after moving forward a certain amount, one of the opposing links is rotated relative to the other link that stops moving. Those using a link mechanism that allows the hook-shaped scalpel to draw a J-shaped trajectory or those that use a cam mechanism, for example, as shown in the following example, a J-shaped path is attached to a movable plate on which a hook-shaped knife is attached. An example is one that uses a cam mechanism in which a pair of guide holes are provided and guide bottles are fitted into each, and the movable plate is moved in a J-shape by an operating mechanism such as an air cylinder connected to the movable plate. be able to.

The receiving knife driving means for advancing the receiving knife toward the looper includes, for example, a spring, a cylinder, a solenoid, a linkage mechanism, or a lever that is pushed and held in the opposite direction to the acting direction by a detachable stopper. , a mechanism for striking the receiving knife with the lever and an operating mechanism for the mechanism, and a means for moving the receiving knife forward in relation to the retraction of the hook-shaped knife includes a mechanism in which a fixed amount of the hook-shaped knife is moved forward. A limit switch that detects when it retreats and issues an output signal to the receiving knife drive means, a sensor such as a filler, a pin that removes the stopper from the spring and releases the spring, and a certain period of time after the hook-shaped knife starts to retreat. An example of this may be a timer that issues an output signal to the receiving knife drive means.

Embodiment Figure 1 shows a multi-row double chainstitch sewing machine, with bed 1
Inside, a plurality of loopers 3 are arranged in parallel, which move back and forth along the cloth feeding direction and cooperate with the loopers 3 to form a double chain stitch.
A thread cutting device, generally designated by reference numeral 4, is provided on the side of the looper.

As shown in detail in FIGS. 2 to 4, the thread cutting device W4 includes a guide path 5a extending in the left-right direction toward the looper 3, and a guide path 5a extending in the left-right direction toward the looper 3.
A movable plate 6 is formed with a guide path 5b extending in the front-rear direction along the looper and has a pair of L-shaped guide holes 5 toward the looper, and is slidably fitted into each guide hole 5 of the movable plate 6. a pair of fixed guide pins 7, and a thin plate-like mounting plate 11 that is attached to the movable plate 6 so as to be adjustable in position in the left and right direction by a set screw 9 that is fixed to the movable plate 6 through a long hole 8. , hook-shaped scalpels 12 are attached to the mounting plate 11 in the same number as the loopers 3 and in parallel at the same intervals as the loopers, and are diagonally connected to the movable plate 6, with the piston rod 14 extending along the guide path 5a. An air cylinder 15 that advances and retreats with a motion component and a motion component along the guide path 5b, and is slidably supported by a rod 16 that extends in the left-right direction and has one end fixed to a fixed member 13, and has a cutting edge formed at its tip. Receiving knife 17 and receiving knife 1
A plate spring (not shown) attached to the lower side of 7 and a receiving knife 1
A guide member 21 has a guide groove 19 into which a protrusion 18 protruding to the side of the rod 17 fits, and guides the movement of the receiving knife 17 along the loft 16 to stop the rotation of the receiving knife 17. A coil spring 22 that urges the knife 17 to the left in the figure, and a claw lever 24 that is pivotally supported on the sewing machine frame and that removably engages with the protrusion 23 of the receiving knife 17 to lock the receiving knife 17.
, a helical spring 25 that urges the pawl lever 24 to rotate counterclockwise in the figure, a stopper pin 26 that restricts the movement of the pawl lever 24 in the counterclockwise direction, and a stopper pin 26 that presses the pawl lever 24 at the bent portion. A bell-crank-shaped release lever 28 is pivotally supported on the same shaft, and a tongue piece 29 is hooked on the claw lever 24 and the release lever 28 and opens both levers to cause one example of the release lever 28 to protrude upward from the claw lever 24. a helical spring 31 that is engaged with the release lever; a protrusion 33 that protrudes from the side of the movable plate 6 and engages with the step 32 of the receiving knife 17; A pin 35 engages with the other side of the lever 28 to rotate the lever 28.

Thread cutting by this device is performed as follows.

The thread cutting device 4 is always in the state shown in FIG. 2, and when performing thread cutting, the air cylinder 1 is
The switching valve 5 (not shown) is switched to cause the piston rod 14 to protrude. The movable plate 6 is guided by the guide pin 15 due to the motion component along the guide path 5a and moves to the left in the figure. By the time the right end of the guide path 5a reaches the guide pin 7, the pin 35 engages with the release lever 28, and the lever 28 is rotated counterclockwise in the figure against the action of the helical spring 35. When the pin 35 comes off the tip of the release lever, the release lever 28 rotates clockwise in the figure and returns to its original position. When the right end of the guide path 5a reaches the guide pin 7, the pin 35 is located on the left side of the release lever 2 (
(See FIG. 3), each hook-shaped knife 12 is located behind each corresponding looper 3 at the time when the right end of the guide path 5a engages with the guide pin 7. From this piston rod 1
When the movable plate 4 protrudes further, the movable plate 6 is guided by the guide pin 7 due to its motion component along the guide path 5b and is pushed downward in the figure. As a result, each hook-shaped female 12 is connected to the receiving female 17.
The needle sticks out further, moves forward along the loopers 3, and passes through the needle thread loops hung on each looper 3. Figure 3 shows guide route 5b.
The rear end is engaged with the guide pin 7, and the hook-shaped knife 12 is shown in a state where it has reached the forward end, and FIG. 6 shows the hook-shaped knife 12
The state when the thread has passed through the needle thread loop 41 is shown.

In the figure, 37 is a needle hole formed in the throat plate 38 (see FIG. 1), and 40 is a retainer. This retainer moves perpendicular to the direction of movement of the looper. In other words, when the looper advances toward the front, it engages the looper thread connected to the seam from the left and moves to the right, pulling the louver thread away from the looper and widening the space between them to ensure that the needle can be inserted between them. .

As described above, the hook-shaped knife 12 moves to the left facing the looper during thread cutting, and after reaching behind the looper, moves forward along the looper in an L-shaped trajectory. FIG. 5 shows the trajectories of these hook-shaped scalpels.

Immediately after the hook-shaped knife 12 reaches the forward end, the switching valve of the air cylinder 15 is switched again and the piston rod 14 begins to retract. Accordingly, the movable plate 6 moves in the opposite direction to that described above, and the hook-shaped knife 12 moves back along an L-shaped trajectory. That is, first, the movable plate 6 is guided by the guide pin 7, and moves backward until the pin 7 reaches the front end of the guide path 5b (the right end of the guide path 5a), and the hook-shaped knife 12 moves backward on the looper. On the way, the needle thread loop 41 and the louver thread 42 that are hung on the looper 3 are captured and once pulled rearward. Then, as the movable plate 6 moves to the right, it is pulled to the right. When the movable plate 6 moves to the right by an appropriate amount, the pin 35 engages with the release lever 28 as shown in FIG. The lever 24 is rotated in the same direction to release the engagement with the protrusion 23 of the receiving knife 17.

The receiving knife 17, which is unlocked by the pawl lever 24, jumps out to the left in the figure by the action of the coil spring 22, and each hook-shaped knife 12 is inserted between the cutting blade at the tip and a leaf spring (not shown) that is pressed against the lower surface of the receiving knife 17. Pinch, each hook-shaped female 12
The needle thread 41 and looper thread 42 caught in the needle thread 41 and looper thread 42 are cut. Note that the receiving knife 17 is stopped from moving to the left by the stepped portion 32 engaging with the protruding portion 33 of the movable plate 6 that moves to the right. FIG. 4 shows the state at the time when the stepped portion 32 engages with the protruding portion 33 and thread cutting is completed. When the movable plate 6 hangs and moves to the right, the receiving knife 17 is also pushed back to the right by the protrusion 33 against the action of the coil spring 22. On the way, the pin 35 moves backward as it comes off from the release lever 28, and the receiving knife 17 is moved back to the claw lever 24, which has been engaged with the stopper pin 26 and returned to the state shown in FIGS. 2 and 3. The protrusion 23 is engaged. The retaining portion of the tip of the receiving knife with the protrusion 23 is an inclined surface 24a as shown in the figure, so as the protrusion 23 moves to the right in the figure, the claw lever 24 is moved by the helical spring 2.
It is pushed up against the action of 5. Immediately after the protrusion 23 passes, it moves back, engages with the protrusion 23, locks the fixed knife, and returns to the state shown in FIG. 2.

Effects of the Invention As described above, the present invention is a multi-row double chain stitch sewing machine in which the loopers are lined up front and back along the cloth feeding direction, in which the thread cutting device is arranged on the side of the looper, and the hook-shaped knife is attached to the looper when cutting the thread. , then advance and retreat following the route along Rupa,
When retracting, the thread is cut in cooperation with a receiving knife that moves in the opposite direction.The thread cutting device is used to cut threads, which was previously done manually using scissors in this type of sewing machine. The thread cutting device is placed on the side of the looper, so it can be installed not only on sewing machines with a normal size bed but also on sewing machines with a cylindrical bed. moves towards the looper and cuts the thread in cooperation with the hook-shaped knife on the way back, so the cut end of the thread can be cut to an appropriate length without being too long or too short. Since the knives are counter-operated and move in opposite directions, the time lag between the hook-shaped knives when cutting the thread is reduced, making it possible to cut the thread instantaneously. It has the effect of making it possible to align the

[Brief explanation of the drawing]

Figure 1 is a perspective view of a multi-row double chainstitch sewing machine, Figure 2 is a plan view of the thread cutting device installed in the bed of the sewing machine in normal operation, and Figure 3 is when the hook-shaped knife has reached the forward end. Fig. 4 is a plan view when thread cutting is completed, Fig. 5 is a diagram showing the trajectory of the hook-shaped knife, and Fig. 6 shows the state when the hook-shaped knife passes through the needle thread loop. 1'. Bed 3. Looper 4. Thread cutting device 5.
・Guide hole 6・・Movable plate 7・・Guide pin 12・・Hook-shaped female 15・・Air cylinder 17・・Reception knife 22・・Coil spring 24・・Claw lever 25.3
1... Helical spring 28... Release lever Applicant Pegasus Sewing Machine Manufacturing Co., Ltd. Agent Patent attorney Akira Sato - No. 11!1

Claims (1)

[Claims] Consists of multiple needles arranged in parallel in a direction perpendicular to the cloth feeding direction, and multiple loopers that reciprocate along the cloth feeding direction and cooperate with each needle to form multiple rows of double chain stitches. In a multi-row double chainstitch sewing machine, a plurality of hook-shaped knives are installed corresponding to each looper so as to be able to reciprocate between the upper side and the side of the looper, and the hook-shaped knife faces the looper.
A hook-shaped knife driving means that bends or bends near the looper and advances or retreats along a path along the looper, a receiving knife that is supported so as to be movable toward the looper, and a hook-shaped knife that is related to the retreat of the hook-shaped knife from the looper. and a receiving knife driving means for advancing the receiving knife toward the looper, and the hook-shaped knife cooperates with the receiving knife to cut the yarn when the hook-shaped knife retreats. Thread cutting device for chain stitch sewing machine.