JPS605004Y2 - Yarn drawing device - Google Patents

Description

[Detailed description of the invention] The present invention compares the movement of the yarn to a type of flow due to the play between the joints in each roller drive shaft when starting and stopping the drawing in the drawing process of synthetic fibers. This invention relates to a device for eliminating slack in a yarn drawing device that causes slack in the yarn between a roller on the upstream side and a roller on the downstream side, and thereby preventing yarn breakage and yarn coming off from the rollers. be.

A device for drawing fiber threads generally includes a roller for supplying and drawing the thread, a drive shaft to which the roller is attached, a gear train for rotationally connecting the drive shaft, and a motor for rotating the drive shaft, etc. It is made up of other things.

For example, the yarn drawing device according to the present invention comprises elements as shown in the partial perspective view of FIG.

That is, from the upstream side of the yarn Y, the device first passes a feed roller 1 for feeding the yarn Y to the drawing device, a hot roller 2 for heating the yarn Y, and a feed roller for feeding the yarn Y to the feeding roller. The yarn Y is applied to each of the draw rollers 3 for drawing the yarn Y by rotating at a higher speed than the draw roller 3 for drawing. 4 or by the high-speed motor 5 (via the one-way clutch 6 when moving the low-speed motor), (4)
Gear train 7 ←→ Drive shaft 8 of the feed roller 1, (B)
Gear train 7←→Drive shaft 9 of the hot roller 2 (a joint 10 is provided in the middle of the drive shaft 9)←→A bevel gear 11 that transmits the rotation of the drive shaft 9 to the hot roller 2;
and a driven shaft 12 connecting the hot roller 2, and (C)
Through a bevel gear driven shaft (not shown) (in the above, ←→“ means rotationally connected), as in the case of the gear train 74-→the drawer 3←→(B), A method of drawing undrawn yarn using this type of apparatus, which is configured to rotate, has been widely used in the past.

However, in recent years, there has been a demand for higher stretching speeds for the purpose of improving productivity, and it has become necessary to operate the stretching equipment at high speeds.

Therefore, when we sped up the conventional stretching device, that is, the stretching device without the brake 14 shown in Fig. 1, the speed of each roller increased rapidly at the start of stretching, resulting in frequent yarn detachment and yarn breakage. became.

When I searched for the cause, I discovered the following facts:

That is, as shown in FIG. 1, the hot rollers of a normal stretching apparatus made of the above elements are driven by a drive shaft via a pair of bevel gears or the like for each weight.

For purposes of centering during assembly, etc., the drive shaft is usually divided into units of several spindles and connected by a joint with elastic deflection or some play.

Therefore, when starting up or speeding up the stretching device, every time the torque of the motor or the like transmitted to the drive shaft is transmitted to the joint, there is a delay in torque transmission by the amount of play or deflection of the joint.

(In this invention, this play is referred to as play.) On the other hand, the drive shaft of the feed roller usually has less play than the drive shaft of the hot roller, so as a result, the feed roller temporarily overfeeds. The yarn is fed and slackens between the rollers.

In the end, in the case of the above-mentioned conventional drawing device, the cause of the yarn coming off at the start and yarn breakage is that the yarn becomes slack between the feed roller that supplies the yarn and the hot roller that heats the yarn.
This phenomenon is observed when a stopped drawing device is started, when the speed is increased from low-speed operation to steady operation for threading, etc., and when the drawing device is stopped.

In order to solve this problem, attempts have been made to gradually increase the speed of each roller by using speed-controllable motors, but these methods result in larger equipment and higher equipment costs. There were drawbacks.

As a result of extensive research, the inventors of the present invention have found that by attaching inexpensive elements to the conventional drawing device, it is possible to almost completely prevent the yarn from coming off and breaking at the start of drawing. This discovery led us to the present invention.

Therefore, the object of the present invention is to create a yarn that slackens between the rollers on the upstream side and the rollers on the downstream side due to the play between the joints of each roller drive shaft when drawing starts and stops. An object of the present invention is to provide a device that can prevent yarn from coming off the rollers and breaking the yarn in a stretching device.

This purpose is to create a device that is equipped with an element that actively applies torque to the drive side shaft end of the roller in a direction that substantially eliminates the play, that is, in a direction opposite to the normal rotation direction of the roller drive shaft. This is achieved by doing this.

In other words, in order to reduce the driving force, torque is applied in the opposite direction to the normal rotational direction of the drive shaft on the shaft end of the driven side (the side opposite to the driving force transmission side) of the drive shaft where the play cumulatively increases. In this state, the device is started and speeded up, with no play in the normal direction of rotation.

Although the present invention will be specifically explained with reference to drawings, the device of the present invention is not limited thereto, and the present invention can be applied to other yarn drawing devices as long as the essential technical idea of the present invention is followed.

FIG. 1 is a partial perspective view of the apparatus according to the present invention, FIG. 2 is a graph for conceptually explaining the relationship between stretching speed and time, and FIG. 3 is a diagram showing the apparatus according to the present invention. FIG. 4 is a graph showing the operating time of the brake, which is one of the elements for applying torque, and FIG. 4 is a graph similar to the above when the device of the present invention is operated in another manner.

As mentioned above, the main parts of the device of the present invention are the same as the conventional device.

However, in the device according to the present invention, a drive system including drive shafts 8, 9, 13, preferably a drive system having the largest amount of play, and in the device of FIG. It differs from conventional devices in that it has an element at the end that actively applies torque in a direction that substantially eliminates the play.

Therefore, the device of the present invention has certain elements added to the conventional device.

The brake 14, for example, an electromagnetic friction brake, is typically used as the element, but it is of course possible to use any device that reduces the driving force of the drive shaft, such as an air motor. .

Next, its effect will be explained.

Now, when starting the stretching device, it is first started by the low speed motor 4 from a stopped state.

At this time, due to the presence of the elastic joint 10, the closer the drive shaft 9 of the hot roller 2 is to the driven side, the later the activation thereof is than the feed roller 1, so that the yarn becomes slack between the feed roller 1 and the hot roller 2.

Generally, when the thread is slack at this time, the rotational speed of the roller is still low, so thread slippage and thread breakage are less likely to occur.

Next, let's consider when speeding up from low-speed operation to high-speed operation.

Draw roller 3 is used as hot roller 2 during low speed operation.
A large stretching tension is applied from the shaft, the tension of each weight is added, and a force that tries to rotate the drive shaft 9 in the driving rotation direction is exerted from the driven side, and the driven shaft side moves ahead by the amount of play in the joint 10. There is.

If the speed is rapidly increased by the high-speed motor 5 in this state, there will be a delay in the transmission of drive torque by the motor at the part where the slack effect is exerted, and in particular, the speed-up timing of the hot roller 2 near the driven side of the drive shaft 9 will be delayed. As a result, the yarn becomes slack between the hot roller 2 and the feed roller 1.

Therefore, when the brake 14 is operated at low speed as indicated by the broken line A in FIG. 2, the broken lines A and B in FIG.

Let it work in advance as shown in C.

Then, since the play has become smaller, there will be no delay in the hot roller 2 when speeding up at the next high speed.

Therefore, the yarn does not become slack.

On the other hand, if the stretching device is to be stopped after normal operation at high speed, the brake 14 is applied as indicated by broken lines B and C in FIG.

Then, at the next low speed start, hot roller 2
There is no longer a delay, and no more thread coming off the rollers or thread breakage.

In addition, as a means to prevent a delay in the hot roller 2 when starting the stretching device from a stopped state, the above-mentioned through-rebrake is installed as shown in FIG. 3B.
However, if you use a device that gradually starts the low-speed motor 4, such as a powder clutch or an acdle starter, the rise in the stretching speed will be smoother as shown in Figure 4, and the speed will be even higher. It is possible to completely prevent yarn slack.

By installing the device according to the present invention, the delay of the hot rollers at the start of stretching is eliminated, so yarn slack and yarn breakage can be prevented, and the effects of reducing the amount of waste yarn and the number of working personnel are extremely large.

As an actual example, when drawing a 100 denier polyethylene terephthalate yarn, the start success rate, which was previously about 80%, was improved to over 98% by applying a brake as shown in FIG. 3B.

This invention can be applied not only to a device for drawing polyethylene terephthalate yarns, as shown above, but also to devices for drawing other synthetic fibers.

The device according to the invention is particularly useful in pinless stretching devices.

This is because a pinless stretching device does not have a stretching pin for fixing the stretching point, which is normally provided between the feed roller and draw roller of a stretching device. This is because it is much more difficult than.

Then, by eliminating slack in the yarn at the start of stretching and when speeding up,
Being able to change the speed is important for stabilizing pinless drawing operations.

Since the device of the present invention can be applied to a pinless stretching device, the present invention has great industrial significance.

[Brief explanation of the drawing]

FIG. 1 is a partial perspective view of the yarn drawing device according to the present invention, FIG. 2 is a graph for conceptually explaining the relationship between drawing speed and time, and FIG. 3 is a graph showing the relationship between the drawing speed and time. 4 is a graph showing the time or period for operating the brake, which is one of the elements that apply torque in the device;
The figure is a graph similar to the above when the device of the present invention is operated in a different manner. 2 to 4 correspond to each other in terms of time. Y... Yarn, 1... Feed roller,
2...Hot roller, 3...Draw roller, 4...Low speed motor, 5...High speed motor, 6...One-way clutch ,7...
・Gear train, 8...Feed roller drive shaft, 9・
... Hot roller drive shaft, 11 ... Bevel gear, 13 ... Draw roller drive shaft, 14.
·····brake.

Claims (1)

[Claims for Utility Model Registration] In a yarn drawing device in which roller drive shafts are connected by a plurality of joints, a shaft end on the driven side of the roller drive shaft is provided with a shaft opposite to the normal rotation direction of the roller drive shaft. Apply torque in the direction. A yarn drawing device characterized by being provided with an element.