JPS5943564B2 - How to set the draft limit value in a draft device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for determining a draft ratio limit value in a draft device of a spinning machine, particularly in a three-wire draft device.

In a spinning machine that skips the roving process and directly feeds sliver for spinning, the non-twisted sliver with filaments is drafted by a three-wire draft device equipped with a back roller, a middle roller with an apron, and a front roller. In this case, the total draft ratio between the back roller and the front roller is as large as 100 to 400 times.

This total draft ratio is the break draft ratio between the back roller and middle roller, and the middle roller.

This relationship is divided into the main draft ratio between the front rollers and the main draft ratio between the front rollers.

The striated sliver is an aggregate of non-twisted fibers.
The parallelism of the fibers in the sliver varies greatly depending on the type of fiber and blending rate, and even if the fibers are the same and the blending rate is the same, depending on the previous spinning process. However, the limit value of the total draft ratio as a revisit range and the draft distribution between the break draft and the main draft differ each time, so conventionally, spinning experiments were conducted at various draft ratios each time, and the results were investigated and implemented. I was working on doing that.

This was very time consuming and sometimes confusing.

The present invention has been made in view of this problem, and it is possible to determine the degree of fiber aggregation based on the apparent thickness of the sliver and gelatin, and determine the revisit range, that is, the draft limit value and draft distribution, based on this. This is how it was done.

It has long been known that there is some relationship between the apparent thickness of a sliver and its spinnability, and in fact, slivers with a smaller apparent thickness have better spinnability, while larger slivers are more difficult to spin. was the general trend.

The present invention attempts to quantify this apparent thickness, and further captures this value by replacing it with the degree of aggregation of fibers, organizes the above trends based on this, and selects and sets a critical point for revisiting from among them. It was extremely successful.

The present invention will be explained in detail below.

What is shown in FIG. 1 is a device for measuring the apparent thickness of a sliver, and this device consists of a measuring device body 1, a pressure plate 2, and a weight 3.

The measuring device main body 1 is provided with a groove 4 having a horizontal U-shaped cross section in the front-rear direction, into which the sliver S is inserted, and a predetermined number of slivers S, for example, about 10 slivers S, are bundled and laid in parallel in this groove.

A scale 5 indicating the depth of the groove 4 is provided on the front and rear sides of the main body 10.
are engraved on both sides of the groove 4, so that the value can be easily recognized from the outside.

The groove 4 has a front-to-back width of 10 crrL, a left-right width of 2 crrL, and a depth of about 8 cIrL, and its bottom and inner surfaces are formed into smooth horizontal and vertical surfaces, respectively.

The pressure plate 2 includes a pressure plate 6 whose longitudinal width and horizontal width are the same as the groove 4, and two guide plates γ and 7 which are erected on the pressure plate 6 and whose left and right widths are the same as the groove 4. and is slidably fitted into the groove 4.

The weights 3 are prepared from several metal plates whose front and rear widths are approximately equal to the spacing between the guide plates 7 and 70, and whose weight is 50 mm.
y' or 1001, etc.

The guide plates 4, 4 are arranged at the front and rear ends of the pressure contact plate 6, and the weight 3 is placed between them to press the sliver S evenly.

In this state, read the vertical width of the sliver S on the scale 5, and perform the same operation while increasing the number of weights 3 sequentially.
Record the read values on the graph.

An example of this graph is shown in FIG.

By connecting the numerical points on this graph with a line and extending it naturally, you can find the value when no load is applied.

In this example, it is point (a), that is, 50 tomo.

This does not indicate the cross-sectional area of a single sliver, but is a scale value for 10 slivers in the measuring device, but for convenience, this value will be used as a thickness value representative of the sliver thickness in the following description.

Generally used filamentous slivers have different weight per unit length, that is, one sliver, so the thickness value can be simply compared for each sliver and corrected according to the following formula: There is a need to.

In the above formula, one target sliver refers to the grain of the sliver that is the target of this example whose thickness value was measured, and one reference sliver refers to the predetermined sliver used as a standard for comparison with other slivers. It is a gelen.

As is clear from the above equation, the correction value is understood to include various conditions such as the parallelism of the sliver and the clinging of the fibers, and the above-mentioned degree of aggregation of fibers means the correction value.

Here, the thickness values of various slivers were measured as described above, correction values were calculated, and spinning experiments were conducted for each of the slivers.The results are shown in the following table.

The spinning equipment used to create this table is No. 4.5,
Shown in Figures 6 and 7.

However, the invention is not limited only to the devices described below.

Namely, U.S. Pat. No. 4,112,658 for air spinning apparatus.
No. 4,169,350, No. 4,183,202, No. 4,142,353, and U.S. Patent No. 3 relating to the knot spinning method.
No. 079746, No. 3978648, No. 4003
No. 194, and is also applicable to ordinary ring spinning machines, open-end spinning machines, etc.

In FIG. 4, the sliver s in the can 8 is drafted by a drafting section 12 composed of a back roller 9, a middle roller 10, and a front roller 11, and turned into thread by a nozzle section 13.

This spun yarn Y is pulled out by a delivery roller 14, passes through a yarn unevenness detection section 15, and then passes through a friction roller 1.
6, a winding section 19 that is rotatable around a shaft 17, and is composed of a ladle 18 and a bobbin P supported by the cradle.
At this point, it is wound onto a bobbin P.

The Notsuta one-carriage 20 has a rail 22 inside the frame 21,
The knotter cart 20 travels along the line 23 and stops at the spinning unit that has not cut the material.

At that time, the suction pipe 25 pulls out the yarn from the nozzle 13, the suction pipe 26 pulls out the yarn from the bobbin P, and then both the yarn from the nozzle and the yarn from the bobbin are introduced into the knock 24 to perform yarn splicing. .

In addition, SP in FIG. 4 is a suction pipe for removing thread waste and fluff.

The draft section 12 is shown in FIG.

The sliver S is introduced into a sliver guide 2T whose inside is tapered and pulled out from the guide 27 by a back roller 9.9-1.

Back roller 9.9-1 and middle roller 10, 10-1
A break draft is performed between the back roller and the middle roller, and a guide 28 is provided between the back roller and the middle roller to prevent the width of the sliver from expanding more than necessary.

Next, a main draft is performed between the middle roller 10° 10-1 and the front rollers 11 and 11-1.

The sliver is then introduced into the nozzle 13 and spun out as yarn Y.

In addition, trough hack roller 9, top middle roller 10
, the dog front roller 11 is the draft cradle 2
They are placed independently on both sides with 9 in between.

On the other hand, bottom back roller 9-1, bottom middle roller 1
0-1. The bottom front row 211-1 is formed on a line shaft that is shared by all spinning units.

Therefore, the draft ratio between the back roller, middle roller and front roller is changed in the machine-side gearbox.

In FIG. 6, a motor M1 drives a bottom back roller 9≧-1, a bottom front roller 11-1, a delivery roller 14, and a friction roller 16 via a reduction gear and other gears.

In addition, the motor M2 causes the bottom middle roller 10-1 to
to drive.

Therefore, the back roller 9-1 and the front row 211-1
The total draft ratio determined between gears 30, 31,
The break draft ratio is set by replacing the gear 33 or the rotation speed of the motor M20.

Details of the drive system shown in FIG. 6 can be found in US Patent Application No.
No. 257510 (filed on April 27, 1981) for details.

Details of the nozzle 13 are shown in FIG.

The nozzle 13 is composed of two nozzles 34 and 35,
The swirling directions of the airflows ejected from the nozzles 34 and 35 are opposite to each other.

The nozzle 34 has an orifice 36 inclined to the passage 38, and the nozzle 35 has an orifice 37 perpendicular to the passage 39.

Further, the nozzle 34 has an aperture 40, 41, and the nozzle 35 has an aperture 42.

In the table, A1-A4 are 100% polyester, B1
~B4 is a blended yarn of polyester and cotton, 01~C8 is a blended yarn of 100% acrylic or acrylic and cotton, D1~D3
shows the case where 100% vinylon thread is used.

The experiment used a three-wire draft device, and the main draft ratio was set to 30 times.

Also, in the table, U%, Th1n, Th1ck, Nep for the product of correction value and break draft ratio (BDR)
Figure 2 is a graph of the relationship.

Here, each straight line and curved line represents a trend of the above relationships, and the characteristics of each relationship are prominently displayed, and this trend is expected to become even more pronounced as the number of samples is increased.

What we know from this diagram is that the product of the correction value and BDR is 30
250, if it exceeds 0, the spinning quality will be extremely deteriorated.
There is almost no problem below, and the critical point is estimated to be around 250, although it depends on the required yarn quality, and this is hereinafter referred to as the break draft limit coefficient.

That is, the coefficient serves as a guideline for setting the revisit range in the drafting device, and is understood to have general validity for various slivers.

The usage of this is therefore that the main draft ratio of the spinning machine is 3.
0 times, the correction value of the sliver to be spun is 40
If mm, then BDR=250÷40=6.25 (times), and the total draft ratio (TDR) is TDR=30.
X6.25=197.5 (times).

In this way, according to this method, by conducting experiments in advance using various slivers in the drafting device and determining the break draft limit coefficient unique to the device, the thickness value of the sliver to be spun can then be determined. You can easily know the limit of the break draft ratio just by measuring it.

In addition, in the above method, it becomes the object of measurement and experiment.

It goes without saying that the number of slivers that may be used must be the same for each sliver.

Similarly, the actual cross-sectional area may be used as the thickness value or correction value of the sliver (or this may be a value under a constant load).

Furthermore, in the above experiment, the main draft ratio was kept constant and the break draft ratio was varied, but instead of this, the main draft ratio, break draft ratio, and total draft ratio could be rearranged and used. good.

As explained above, according to the method of the present invention, the draft limit value can be easily set by measuring the thickness value of the sliver to be spun, and the work efficiency can be greatly improved.

[Brief explanation of drawings]

Fig. 1 is a perspective view showing a measuring device used in the present invention, Fig. 2 is a graph showing sliver thickness values under each load state, and Fig. 3 is a graph showing the yarn quality as a function of the product of the correction value and the break draft ratio. It is a graph showing a relationship. FIG. 4 is an overall side view of the spinning apparatus in which the method of the present invention is implemented, FIG. 5 is a side view of the draft section, FIG. 6 is a schematic diagram of the drive system, and FIG. 7 is a sectional view of the nozzle section. .

Claims (1)

[Claims] 1 Correcting the thickness values of various slivers by comparing the gelatin of the slivers with a predetermined reference value,
A method for setting a draft limit value in a draft device, characterized in that the limit of the draft ratio of the sliver to be used is determined from the relationship between the product of the correction value and each draft ratio and the quality of the spun yarn corresponding to the product.