JPH071110Y2 - Thread knotting device for sewing machine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a thread knotting device for connecting old and new threads at the time of thread replacement in a sewing machine, particularly a lock sewing machine.

[Prior art and its problems] When the threading operation is advanced and the thread winding is replaced with a new thread, it is necessary to connect the old and new threads.

That is, the old thread that is set on the sewing machine and that is engaged with the stitch forming mechanism such as the needle or looper is cut at an appropriate point to be connected, the old thread winding is cut off, and the new thread end of the new thread winding is cut off. The old and new threads must be connected by connecting the part to the end of the old thread mounted on the sewing machine.

The connection work between the old and new yarns, that is, the yarn knot, has conventionally been performed manually by the following procedure. First, the thread amount of the thread winding set in the thread winding holder is watched, and when the remaining thread amount is low, the driving of the sewing machine is stopped.

Next, cut the thread from the thread winding to the stitch forming mechanism at appropriate points, replace the old thread winding with the new thread winding, attach the new thread winding to the holder, and the end of the new thread and the end of the old thread remaining on the sewing machine side. After connecting and, the sewing work is restarted. Such a manual thread knot is complicated, and the knot is apt to be uncertain and improperly shaped, which causes a serious hindrance to the sewing operation.

For this reason, an attempt has been made to carry out the thread knotting operation with a thread knotting machine called a so-called knotter.
Simply substituting the knotting operation with a knotting machine requires threading work in the knotting machine and other fine manual work, and as a whole is almost the same as the manual work.

Also, thread waste is generated by cutting the thread, and the knotter is entangled.
The knotter sometimes stopped working.

[Summary of the Invention] The present invention has been made in order to solve the above-mentioned problems, and a thread knotting device of a sewing machine is provided with an old thread wound with an old thread stretched in advance at a predetermined position of a thread knotting device. A yarn supply cassette, a yarn supply cassette of a new yarn in which a new yarn is stretched at a predetermined position parallel to the old yarn on the yarn knotting device, and a drive source that raises and operates the yarn knotting device to connect the old and new yarns, An object of the present invention is to provide a thread knotting device which is configured with a thread clasp arm that loosens a thread when the thread is slid, makes the thread knotting at the time of threading and replacement quick, reliable and easy, and does not generate any thread waste.

The thread from the thread winder of the thread supply cassette passes through the information of the thread knotting machine, passes through the thread fastening mechanism, and is set in the stitch forming mechanism such as the needle and the looper. When the sewing operation progresses and the amount of thread wound in the cassette becomes less than or equal to a predetermined amount, the driving of the sewing machine is stopped first.

Next, a new yarn supply cassette is prepared, the yarn is pulled out from the yarn winding device, tensioned at a predetermined position and tensioned, and then the new yarn supply cassette is attached to the cassette fitting portion on the yarn tying device.

As a result, above the thread knotting machine, the new thread stretched in the new thread supply cassette and the old thread extending from the thread winding of the thread supply cassette of the cassette mounting section to the stitch forming mechanism are stretched in parallel. To be done.

When a new thread supply cassette is set in the cassette fitting section and both the old and new threads are placed side by side at the upper position of the thread combing machine, the thread knotting machine rises to start the thread knotting operation and When is finished, it descends and returns to the original position. Then, remove the old thread supply cassette from the cassette mounting section and replace it with the new thread supply cassette of the cassette fitting section to the cassette mounting section provided on the side of the thread knotting machine to perform the thread knotting work. Ends.

[Example] An example will be described with reference to the drawings.

FIG. 1 is a perspective view showing a schematic configuration of a thread sewing device according to the present invention implemented in a lock sewing machine.

In the figure, 1 is a lock sewing machine head, 1a is a thread making bar provided on the entire surface of the lock sewing machine 1 for correcting entanglement of threads, and 2 is a cradle 2a fixed to the rear end of the lock sewing machine head.
The yarn tying device attached to the tie is normally submerged in the receiving table 2a, and is raised during the yarn tying operation to join the lower surface of the yarn supplying cassette 4 described later. Further, 2b is a cassette fitting portion for standing the yarn supply cassette 4 during the yarn knotting operation. 3 is a cradle
A thread retaining arm having a concave shape provided on the front surface of 2a as a thread retaining mechanism. Both ends of the thread retaining arm are pivotally supported by both side surfaces of the pedestal 2a and are rotatable. Further, 3a is a threading portion provided on the thread retaining arm.

The reference numeral 4c designates a cassette mounting portion provided on the back surface of the pedestal 2a, and the thread is supplied from the thread winding of the thread supply cassette 4 mounted here to a stitch forming mechanism such as a needle or a looper. In addition, 8 is an air cylinder as a drive source of the thread knotting device 2.

FIG. 2 is an external perspective view of the yarn supply cassette.

In the figure, reference numeral 4 denotes a yarn supply cassette, which is provided with three yarn winding receivers 4b at its end. Reference numeral 5 denotes a thread winder which is axially supported by the thread winder receiver 4b, and 6 denotes a thread hook which is erected upright on the thread winder receiver 4b and has respective threading holes 6a, 6b, 6c.

4a is a lid of the yarn supply cassette 4, and a yarn hook 7 having a yarn pushing hole 7a is formed at an end thereof.

The thread from the thread winder 5 is guided to a required place through the thread passing holes 6a, 6b, 6c, 7a.

The yarn supply cassette 4 is a new yarn supply cassette 4N,
It has the same structure as the yarn supply cassette 4U of the old yarn.

As described above, the yarn supplying cassette 4, the cassette fitting portion 3b, and the cassette mounting portion 4c constitute a cassette mechanism. 7c is a hook body having a thread hook groove.

FIG. 3 (a) shows the thread knotting device 2 during the stitch forming operation,
FIG. 3 is a partially cutaway side view showing a related configuration of a cradle 2a, a cassette mounting portion 4c, a thread fastening arm 3 and the like.

A yarn supplying cassette 4U of old yarn is attached to the cassette attaching portion 4c, and the yarn T from the yarn winding set in this is supplied.
Passes over the suture knotting device 2 submerged in the cradle 2a,
It is inserted into the threading portion 3a of the thread clamp arm 3. In this state, the thread clasp arm 3 is rotated downward by its own weight and is in contact with the upper surface of the lock sewing machine body 1.

Next, the thread T is directed upward, and after passing through the thread passing hole of the thread making bar 1a, engages with a required portion of the stitch forming mechanism such as a needle or a looper.

FIG. 3B shows the cassette 4U in the cassette mounting portion 4c.
The remaining amount of thread in the inner thread winder 5 has decreased and the cassette mounting section 4c
FIG. 7 is a side view showing a case where the yarn supplying cassette 4U is replaced with a new one.

First, a new thread supply cassette 4N (thread winding 5 as described
The thread end is pulled out from and is inserted into the threading hole 7a. )
Is attached to the cassette fitting portion 2b on the upper surface of the receiving table 2a.

Then, above the thread knotting machine 2, the thread already attached to the sewing machine (the thread from the thread supply cassette 4U of the cassette mounting portion 4c, hereinafter referred to as the old thread) and the lower surface of the new thread supply cassette 4N A thread (hereinafter referred to as a new thread) stretched between the through holes 6c and 7a is arranged side by side.

Next, the thread knotting device 2 is lifted from the pedestal 2a by the cylinder 9, and as a result, both the above-mentioned parallel old and new threads are engaged with the thread crossing mechanism described later in the thread knotting device 2 and also the thread described later While the old and new yarns are connected by the operation of the guide hook and the knotting mechanism, the yarn winding side of the old yarn is cut.

In the thread knotting operation by the thread knotting device 2, a considerable amount of thread is drawn by the engagement of the old and new thread, but the end of the old thread on the side of the stitch forming mechanism is engaged with each part of the sewing machine. Therefore, it cannot be pulled in smoothly. (In particular, in a lock sewing machine, the end portion of the old thread is fixed to the needle plate to form an empty ring.) In order to eliminate this inconvenience, a thread clasp arm 3 as a thread clasp mechanism is provided. At the time of knotting, when the yarn is pulled in the direction of the yarn knotting device 2, the yarn clamp arm 3 is rotated to the position of the broken line as shown in FIG. Retraction is done smoothly. Then, the knot tying device 2 descends and returns to the original position.

In this way, when the connection between the new thread from the new thread supply cassette 4N and the old thread mounted on the stitch forming mechanism of the sewing machine is completed, remove the old thread thread supply cassette 4U from the cassette mounting portion 4c. Instead, a new thread supply cassette 4N in the cassette fitting portion 2b is attached, and the sewing operation is restarted.

FIG. 4 is a partially cutaway perspective view showing a portion of the knotting machine 2.

In the figure, 10 is a first thread cross plate, 10a is a first link that is driven by the cylinder 8 to rotate the first thread cross plate 10, and 10a1 is a thread engaging claw. Reference numeral 11 is a second thread cross plate which is installed at a position facing the first thread cross plate 10 by sandwiching a thread guide hook described later, and 11a is a cylinder 8.
Is driven to rotate the second thread cross plate 11, and 11a1 is a thread engaging claw.

First thread cross plate 10 and second thread cross plate described above
A yarn cross mechanism is constituted by 11, the first link 10a, the second link 12a, and the like.

Further, 10b and 11b are presser springs for pressing the first link 10a and the second link 11a, respectively. 12 is a thread guide hook that is driven to rotate by the cylinder 8, and is a cutter plate 12c.
With the inside being a three-layer structure of hook plates 12a, 12b. The spring pressure of 11b is weaker than that of 10b.

Reference numeral 13 denotes a knot arm as a knot mechanism, which is driven by the cylinder 8 and wound around the yarn guide hook 12 to operate on both the old and new yarns in the front knot state to complete the connection.

Next, based on FIGS. 5 to 7, the yarn knotting of the old and new yarns by the yarn knotting device 2, that is, the connecting operation will be described.

In the figure, B is the yarn supplying cassette 4U of the cassette mounting portion 4c.
B1 indicates the stitch forming mechanism side of the old yarn B, and B2 indicates the yarn supply cassette 4 side. A is a new thread stretched between the threading holes 6c and 7a of the new thread supply cassette 4N mounted in the cassette fitting portion 3b, and A1 is the new thread A.
And A2 indicates the end side of the drawn new yarn.

The old thread B is normally above the thread knotting device 2 and faces both the first and second cross plates 10 and 11.

Then, the new yarn supply cassette 4N is inserted into the cassette fitting portion 2b.
New thread A stretched between the threading holes 6c and 7a when attached to the
Is parallel to the old yarn B and faces the yarn engaging claws 10a1 and 11a1 above the yarn knotting device 2.

Then, with the start of the knotting operation, the knotting device 2
When the thread is raised, the new thread A is engaged with the thread engaging claws 10a1 and 11a1 and the old thread B is engaged with the first and second thread cross plates 10 and 11 respectively.
Engage with. At this point, the yarn guide hook 12 is located between the old and new yarns A and B, and the tip of the yarn guide hook 12 faces upward. (See FIG. 5 (a)) Then, when the first and second links 10a, 11a move in the arrow direction shown in FIG. 5 (b) by the operation of the cylinder 8, the yarn cross plates 10, 11 is each thread engaging claw
By crossing 10a1 and 11a1, the new yarn A and the old yarn B are
Three thread loops are formed and crossed, with the middle thread loop of the three thread loops being in engagement with the thread guide hook 12. (See FIG. 5 (b)) Then, as shown in FIG. 6 (a), the yarn guide hook 12 rotates counterclockwise to engage with the yarn loop in the direction of the first yarn cross plate 10. .

The yarn guide hook 12 further rotates and cuts the old yarn B with the hook plate 12b at a position of about 270 degrees from the original position by rotation about the pin P of the cutter plate 12c.

At this time, the yarn supply cassette 4 side (B2) is cut off, and the other side (B1) is held by the hook plate 12a and the cutter plate 12c. Before the yarn guide hook 12 further rotates and returns to the original position, the old and new yarns engaged with the yarn guide hook 12 are in a front knot state as the yarn guide hook 12 rotates.
That is, when the yarns are tightened, the yarns that are engaged with each other are in a state of being fastened together. (See Fig. 7 (a)) When the thread guide hook 12 rotates to the original position, the knot arm 13
Is operated to pull up and fasten each yarn engaging with the yarn guide hook 12, and the yarn knotting, that is, the connection between the old and new yarns is completed.

By the way, at the time of knotting a thread, if the tensions of the threads to be engaged are made equal, the knot state of the thread becomes defective. Therefore, it is possible to separate the A2 side so as not to apply tension at the time of the yarn knotting operation, but yarn waste is generated and it is necessary to deal with the treatment. Therefore, in this embodiment, since the tension on the A2 side is weakened, the pressing pressure of the second yarn cross plate is weakened against the first yarn cross plate, and a good knot state of each yarn is realized without disconnecting A2. ing.

[Advantages of the Invention] With the configuration and operation described above, the present invention enables quick, reliable, and easy knotting at the time of thread replacement, thereby improving the sewing work efficiency.

In addition, since a plurality of yarns are simultaneously connected and no yarn waste is generated by cutting each yarn during the yarn knotting, a large number of yarn wastes are wound around the yarn knotting device and the operation of the yarn knotting device stops, This has the effect that thread knotting is never impossible.

[Brief description of drawings]

1 is a perspective view of an embodiment according to the present invention, FIG. 2 is an exploded perspective view of a yarn supply cassette according to an embodiment of the present invention, and FIG. 3 is a side view of FIG. The figure (a) shows the time of sewing work, and the figure (b) shows the time of thread threading, respectively. FIG. 4 is a partially cutaway perspective view showing a thread knot like part. 5 to 7 are partially cutaway perspective views showing the knotting operation of the knotting device. 2 ... Thread knotting machine 3 ... Thread clasp arm 4N ... Thread feeding cassette for new thread 4U ... Thread feeding cassette for old thread 6, 7 ... Thread hooking 8, 9 ... Cylinder as drive source 10 ... 1st thread cross plate 11 …… 2nd thread cross plate 12 …… thread guide hook

Claims (1)

[Scope of utility model registration request] 1. An old yarn, which is always located below a yarn path between a new yarn and an old yarn, and which is stretched over the first yarn cross plate and the second yarn cross plate, and in parallel with the old yarn. The new yarn, which is hung on the yarn guide hook, is moved to an intersecting state by the rotation of the first and second yarn cross plates, and
The new yarn and the old yarn are knotted by the rotation of the yarn guide hook,
The old thread is cut by the thread guide hooks, and the plurality of new thread knots that connect the new thread and the old thread to each other, and the machine frame are detachably mounted to accommodate the bobbin of the old thread. At the time of installation, the old thread that hangs on the sewing machine needle is provided on the first cross plate and the second thread cross plate of the thread knotting machine. A new yarn thread supply cassette containing a plurality of thread winding bobbins and a new yarn thread supply cassette are provided. When the new yarn thread supply cassette is placed on the thread knotting machine, the tip of each thread is knotted. A plurality of thread hooks that guide the new yarn so that they are located above the respective thread guide hooks on the device, and after mounting the yarn supply cassette of the new yarn on the yarn knotting machine, raise and operate the knotting machine. When the base is rotatably supported by the drive source and the machine frame, Knotting device in more becomes sewing yarn reservoir arm to engage the yarn rotated by the tension of the yarn during knotting loosen the yarn and between knotting device and the sewing machine the tip.