JPH0213057B2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention aims to improve a weft thread cutting device for a loom, and more specifically, to be capable of reliably cutting inserted weft threads, and to operate the loom 24 hours a day. The present invention relates to a high-precision weft thread cutting device that almost never stops due to a weft cutting error even when continuously operated at high speed.

[Prior art and its problems to be solved]

A weft cutting device rotates a circular cutter disposed on the edge side of a woven fabric so as to face the beating line, and cuts the inserted weft yarn by bringing it into contact with the circular cutter through the beating action of a reed. It is conventionally known (for example, Japanese Utility Model Publication No. 49-41140).

However, in conventional weft cutting devices that cut weft yarns only by contact with a circular cutter, the tension of the inserted weft yarn is weak, or the knotted part of the weft yarn is accidentally cut by the cutter. In addition to easily causing cutting errors if they come into contact with each other, especially when cutting untwisted or glueless weft yarns with poor cohesiveness between fibers, it is important to Because the fibers come apart when they come into contact, it is extremely difficult to cut them completely continuously without leaving a single strand, no matter how sharp a circular cutter you use.
Some errors in cutting had been dismissed as unavoidable.

However, as seen in the recent weaving industry, high-speed looms such as water jet looms and air jet looms have become widespread, and 24-hour full operation has become the norm. This is becoming a problem that has a serious impact on the operating rate of the loom. The reason is that the number of workers has been reduced to the point where it is almost unmanned, and it takes a considerable amount of time and effort to restart a loom that has been stopped due to a weft cutting error.
This is because they will be forced to put in a lot of labor.
By the way, 10 water jet rooms (500 rotations per minute) are equipped with conventional weft cutting devices.
In experiments conducted by the present inventors over 24 hours of continuous operation, it has been confirmed that the operation is stopped due to cutting errors as many as 10 to 20 times, and as many as 5 times.

Due to these circumstances, it has become necessary to improve the precision of the weft thread cutting device, and as shown in FIG. By forcibly rotating both the thread guide rotor R and the thread guide rotor R, the circular cutter 1' is able to rotate and guide the inserted weft yarn Y' by the claws of the thread guide rotor R.
A weft cutting device has been proposed which attempts to cut the weft thread by bringing it into contact with the periphery of the thread (see Japanese Patent Laid-Open No. 45865/1983). However, this improvement plan also had another problem.

From a weaving perspective, the problem is that the rotating guiding body R tends to wind up the inserted weft yarns.
This has the disadvantage that the woven weft threads may be twitched and cause weaving damage, and from a mechanical standpoint, it is necessary to forcibly rotate the thread guide R in addition to the circular cutter 1'. This has the disadvantage that the rotation transmission mechanism has to be complicated, and furthermore, since the dent 22' of the lead 2 facing the cutting device T has to be removed over a considerable area, the life span of the lead itself has to be reduced. The problem is that it may impair versatility.

Although the conventional rotary weft cutting device using a circular cutter has excellent latent qualities in terms of durability and high-speed followability, the present invention
In view of the above-mentioned problems with the cutting accuracy, this was made to improve this problem, and to clear and cut reliably and easily without causing undue stress or twitching to the inserted weft yarn. The object of the present invention is to provide a highly reliable, high-precision weft cutting device that can perform the following steps.

[Means adopted to solve the problem and examples thereof]

The means adopted by the present invention to solve the above technical problems are as illustrated in FIGS. 1 to 9, and are arranged on the edge side of the woven fabric C facing the beating line B. Rotate the circular cutter 1,
In a conventionally well-known weft cutting device in which the inserted weft Y is brought into contact with the circular cutter 1 and cut by the beating action of the reed 2; a plurality of thread hooks 3 are provided on the circumferential surface and are inclined in the direction of rotation;
1, 31... is attached to the cutter rotating shaft 1 so as to be adjacent to the circular cutter 1.
1, the thread hook 3
1, the rotation of the hook foil 3 is stopped when any of the hook wheels 1 receives rotation-preventing resistance due to the engagement of the weft yarn. The gist lies in the provision of a weft holder 21 that partially pushes out the weft yarn Y slightly toward the circular cutter 1 with respect to the beating line B and supports it in a bridge shape.

To explain the illustrated example in more detail, the circular cutter 1 is designed with sharpness and durability in mind.
Usually, those made of ceramic or cemented carbide are selected, but they are not necessarily limited to these, and depending on various conditions such as the desired price, performance, and rotational speed of the loom to be installed. Appropriate materials may be selected accordingly.

In the illustrated example (FIGS. 6 to 9), the circular cutter 1 is placed near the fabric edge on the side of the weft jet nozzle 8 along the beating line B. Rotating axis 1
1 is bracket 1 fixed to loom temple bar A
The circular cutter 1 is rotatably supported by a shaft at the end of the rotary shaft 11, and rotation is transmitted to a pulley 4 provided on the rotary shaft 11, thereby rotating the circular cutter 1. The pulley 4 in the illustrated example is
Rotary transmission mechanism 4, 5, 6, 7 in relation to drive pulley 5, idler pulley 6, and belt 7
The rotating shaft 51 of the drive pulley 5 is rotated in conjunction with the rotation of the main shaft of the loom (not shown). However, the rotation transmission mechanisms 4, 5, 6, and 7 as shown in the illustrated example are not essential to the present invention, and a method is adopted in which the cutter rotating shaft 11 is rotated by a small motor (not shown). In some cases it is not necessary at all.

Next, as the hook foil 3, a ratchet type hook having sawtooth-shaped thread hooks 31, 31, etc. as shown in FIG. A pin foil type one having hooks 31, 31, . . . can be adopted. However, this hook foil 3
is loosely fitted onto the cutter rotating shaft 11 adjacent to the circular cutter 1 so as to rotate along with the rotational movement of the rotating shaft (in the illustrated example, there is a space between the circular cutter 1 and the bracket 12). The more sensitive the sensitivity to the inserted weft Y, the more effective it is, so it is required to reduce the inertial force during entrained rotation as much as possible, so the hook foil itself should be as light as possible, Moreover, it is desirable that the coefficient of friction at the contact portion be as small as possible. Therefore, in the embodiment, the hook foil 3 is made of a plastic material such as oleoresin acetal resin. However, the material of the hook foil 3 is not an essential part of the present invention, and the material of the hook foil 3 is not an essential part of the present invention.
The material of the hook foil 3 does not matter as long as it functions to stop the rotation of the hook foil 3 when it receives rotation-preventing resistance due to the engagement of the weft Y with any one of the hook wheels 1. In addition, the diameter of the hook foil 3 (thread hook 3
1) is usually designed to have approximately the same size as the circular cutter 1, but there is no problem in making it larger than the circular cutter 1 as shown in FIG.

On the other hand, the weft holder 21, which is fixed to the reed 2 in a state facing the circular cutter 1 and the hook foil 3 and supports the inserted weft Y in a bridge shape, is made of a metal fitting whose cross-sectional shape at the weft abutting part is approximately rectangular in the illustrated example. holder recessed part 21 where the weft yarn Y crosslinks.
The size of a is such that the tips of the circular cutter 1 and the hook foil 3 can enter therein.

The weft cutting device of the present invention is generally as described in the above embodiments, but the present invention is by no means limited to the illustrated embodiments, and various design changes may be made within the scope of the claims. Needless to say, it is possible, for example, hook foil 3
The installation position is on which side of the circular cutter (nozzle 8
side or woven fabric C side), and as for the rotational drive mechanism of the circular cutter 1, conventionally known means can be appropriately adopted.

[Function and effect of the embodiment device]

The effects of the apparatus according to the embodiment of the present invention will be explained below based on FIGS. 7 and 8.

Suppose now that the weft Y is ejected from the weft jetting nozzle 8 and inserted into the opening of the weft W, and the beating operation by the reed 2 begins (see FIG. 7). In this state, the weft yarn Y comes into contact with the tip of the weft yarn holder 21 and starts moving forward toward the beating line while forming a bridge on the recessed portion 21a.

Eventually, the bridge-forming portion of the inserted weft yarn Y comes into contact with the circular cutter 1 (see FIG. 8). Therefore, the weft yarn Y is often cut at the moment of this contact.

By the way, the weft Y, which was not cut due to lack of tension or the like due to the contact with the circular cutter 1, is further pushed out by the weft holder 21, and is bent at the beating line position as shown in FIG. Become. Then, one of the thread hooks 31 of the hook wheel 3 hooks the weft yarn Y with a moderate force and presses it against the circular cutter 1, and even after the reeding is finished and the reed 2 starts the backward movement, the weft yarn Y remains This state is maintained until Y is cut off. However, in this case, the time it takes for the weft yarn Y to be cut is not so long, and only a very small time lag occurs, which does not interfere with the next weft insertion.

Since the weft yarn Y is cut using the process described above, there are almost no cutting errors in the apparatus according to the embodiment of the present invention, and in fact, the present inventor installed it in 10 water jet rooms and cut it at 500 rotations per minute for 24 hours. Even in the experimental results of continuous operation, there was not a single machine that stopped operating due to a cutting error.

In addition, in the embodiment shown in FIG. 6, in which the diameter of the hook foil 3 is increased, the hook foil 3 moves to capture the weft yarn Y every time the weft is inserted, so the cutting accuracy is the highest, but the rotation stop frequency is extremely high. It can be said that it is necessary to strengthen the wear resistance of the contact parts.

[Effects of the present invention]

In the weft cutting device of the present invention, a hook wheel that rotates as the circular cutter rotates and a weft holder that supports the inserted weft in a bridge state and presses it toward the circular cutter are skillfully arranged. Therefore, unlike conventional rotary weft cutting devices that use this type of circular cutter, weft cutting errors are almost completely eliminated, dramatically improving the operating rate and productivity of the loom; the hook wheel is rotated by the cutter. Since it is designed to rotate along with the rotation of the shaft,
Unlike the weft cutting device described in Publication No. 55-45865, the weft is not wound up; the circular cutter and hook wheel are coaxially arranged, so it can reliably follow any high-speed loom without causing discrepancies; Since there is no need to drive in synchronization with the beat timing, production costs can be reduced; Since the weft is supported in a bridge shape on the weft holder and cut, there are no disadvantages such as those caused by removing the dent; It has the following advantages, and its industrial applicability is extremely high.

[Brief explanation of drawings]

FIG. 1 is a side view of the apparatus of the present invention, FIG. 2 is a plan view thereof, and FIG. 3 is a sectional view of essential parts showing an example of the connection relationship between the circular cutter, rotating shaft, hook foil, bracket, and pulley in the present invention, Fig. 4 is a side view showing an example of the shape of the hook foil, Fig. 5 is a side view showing another example of the shape of the hook foil, Fig. 6 is an explanatory diagram of the mechanism when the diameter of the hook foil is made larger than the circular cutter, and Fig. 7 9 to 9 are explanatory diagrams sequentially showing the weft cutting process by the device of the present invention, and FIG.
45865).

Claims (1)

[Claims] 1. Woven fabric C facing the beating line B
In a weft cutting device that rotates a circular cutter 1 disposed on the edge side of the fabric and causes the inserted weft Y to come into contact with the circular cutter 1 and cut by the beating action of a reed 2; Multiple thread hooks 3 that can be tilted to
1, 31... is attached to the cutter rotating shaft 1 so as to be adjacent to the circular cutter 1.
1, the thread hook 3
The hook wheel 3 is configured to stop rotating when any of the hook wheels 1 receives rotation-preventing resistance due to the engagement of the weft. A high-precision weft cutting device characterized in that a weft holder 21 is disposed to partially push out an input weft Y slightly toward a circular cutter 1 with respect to a beating line B and support it in a bridge shape. 2. The high precision weft cutting device according to claim 1, wherein the hook wheel 3 is a ratchet wheel having serrated thread hooks 31, 31, . . . . 3. The high-precision weft cutting device according to claim 1, wherein the hook foil 3 is a pin foil having needle-shaped thread hooks 31, 31, . . . that are inclined in the rotation direction. 4. Claims 1 to 4 in which the rotating shaft 11 of the circular cutter 1 is rotated via a rotational transmission mechanism 4, 5, 6, 7.
3. The high-precision weft cutting device according to any one of 3. 5. The high-precision weft cutting device according to any one of claims 1 to 3, wherein the rotating shaft 11 of the circular cutter 1 is rotated by a small motor attached to the circular cutter 1.