JPH0146609B2 - - Google Patents

Description

[Detailed description of the invention]

A. Industrial Application Field The present invention relates to a method for forming a cot in a draw-twisting machine. More specifically, the present invention relates to a method of forming a cot in a draw-twisting machine that allows the winding shape to be freely changed and has good operability. B. Prior Art As shown in FIG. 3, in the conventional method of forming a cot in a draw-twisting machine, when winding the yarn 13 around the package 1, the direction switching valve 16, the oil pump 17, and the oil tank 1 are used.
The ring rail 14 is operated by a hydraulic cylinder 15 driven by a hydraulic cylinder 8. Conventionally, the direction of movement of the ring rail was controlled using a combination of an eccentric cam and a position detector. In this method, the winding shape is determined by the shape of the cam. Therefore, when switching brands or changing the winding shape, it is necessary to change the rotation speed of the cam (gear exchange) and replace the cam. It is not possible to obtain the desired winding shape. Furthermore, there are many moving parts such as rotating parts, contact parts, and sliding parts, which can easily cause failures and require a lot of parts management. C Problems to be Solved by the Present Invention The present invention aims to improve the above-mentioned problems of the prior art and provide a method for efficiently forming pots having various shapes with good operability. It is. D. Means for Solving the Problems The present invention employs the following means to solve the above problems. In other words, in the cot forming device of the draw-twisting machine, an arbitrary package shape is replaced with a corresponding functional formula,
Using this functional formula, the traverse width of the ring rail is calculated by a microcomputer every time the direction of movement of the ring rail is changed, and this is combined with the separately measured traverse width of the ring rail or the moving speed of the ring rail to measure the timing of the rise and fall of the ring rail. This is a tip forming method that uses the results to generate electrical signals to control the reciprocating movement of the ring rail. E Effects and Examples In the present invention, the shape of the package is replaced by a functional expression, but at the same time, the thickness and shape of the yarn, the outer shape of the pirn, the winding width and diameter of the package, the angle of the tapered part, etc. are used as data. By giving the following information, the coefficients of the function are automatically calculated and the shape of the package is determined. The method will be explained in detail below with reference to the drawings. In Fig. 1, the winding diameter 2 of the package 1 at a certain point in time is x, and the vertical distances 3 and 4 of the tapered portion at that time are y ₁ and y ₂ , respectively. y ₁ = f(x) (1) y ₂ = g (x) (2) Assume a function. That is, f(x) is a curve representing the shape of the upper tapered portion, and g(x) is a curve representing the shape of the lower tapered portion. Note that 7 represents the traverse width at a certain point, and 8 represents the winding width of the innermost layer. Now, when x is changed from bobbin outer diameter 5 to package diameter 6 after tip formation, point (x, y ₁ ) and point (x, y ₂ )
The trajectory drawn by is the shape of the package. f(x),
g(x) is a multidimensional equation f(x)=a _n-2 x ^m-2 +a _n-3 x ^m-3 +……+a ₀ (3) g(x)=p _n-2 x ^{m- 2} +p _n-3 x ^m-3 +……+p ₀ (4) However, m is a positive integer greater than 3. Then, the volume v of the yarn from the beginning of winding is given by the following formula. v=A _n x ^m + A _n-1 x ^m-1 +……+A ₀ ………(5) However, A _n ,……A ₀ is a _n-2 ………, a ₀ and
p _n-2 ... is a constant derived from p ₀ , and can be uniquely calculated from the thickness of the yarn. (3)～(5)
Considering the shape of the package generally obtained by a draw-twisting machine, it is sufficient for m in the formula to be 3≦m≦5 (6). Furthermore, it is common to give different coefficients to f(x) and g(x) for one package depending on the range of the winding diameter x, and to vary the winding shape by combining several types of functions. . From equation (5), the final winding amount V ₀ is V ₀ =A _n D ₀ ^m +A _n-1 D ₀ ^m-1 +……+A ₀ (7). If the winding time is N, then V ₁ = V ₀ /N (8) V ₁ is the volume of the yarn that increases in thickness per unit time, but if we consider that the drawing speed is constant, V ₁ is the volume of the yarn that increases in thickness per unit time. It is a constant determined only by the thickness and shape. If J is the time from the start of winding, then V=J×V ₁ , J=1, 2...,N...(9) V given by a discrete value and v in equation (5) are:
If N is set sufficiently large, it can be regarded as Vv. From the above, the following formula holds true. VA _n x ^m +A _n-1 x ^m-1 +......+A ₀ ......(10) From equations (9) and (10) and Figure 1, J→V→x→y ₁ , y ₂ →
Each variable is determined in the order of z, and the traverse width z of the ring rail at each moment can be calculated. In order to raise and lower the ring rail with the traverse width calculated using the above method, the position detector 9 shown in FIG.
10, measure the ring rail speed each time when going up and down,
From the speed and traverse width, the timing of lifting/lowering switching may be calculated by the microcomputer 11 and a signal sent from 12 to the hydraulic system, or the moving distance of the ring rail may be actually measured and the traverse width determined by calculation may be calculated. It is also possible to make a comparison and issue a signal to the hydraulic system at the moment of agreement. In the present invention, a microcomputer (11 in FIG. 1) is used to calculate the traverse width, the ring rail speed, and the winding time, and a schematic flowchart is shown in FIG. 2. Example When forming a cot made of polyester multifilament of 75 denier and 36 filaments, data were set as shown in Table 1, and the results shown in Table 1 were obtained. It can be seen that once the data is set and input in this way, a tip of the form corresponding to the data is formed. Although the tapered portion is a straight line in this example, it may be curved if necessary.

[Table] In the table, the angle of the taper part is as shown in Figure 1.
This is the angle between the straight line showing the taper and the straight line showing the edge of the pan.
F. Effects of the invention According to this method, the shape of the package can be changed freely, and the movable parts associated with the eccentric cam, which are prone to failure, can be omitted, improving operability and the economic effect is tremendous. be.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram of one embodiment of the present invention.
1 is a package, 11 is a microcomputer, and 9 and 10 are position detectors for measuring the moving speed of the ring rail. FIG. 2 is a schematic flowchart of a microcomputer program in carrying out the method of the present invention. Figure 3 shows the area around the ring rail of a conventional draw-twisting machine, where 13 is the yarn to be wound, 1 is the package cage, 14 is the ring rail, 1
5 is a hydraulic cylinder, 16 is a directional control valve, 17 is an oil pump, and 18 is an oil tank.

Claims (1)

[Claims] 1. In the method of forming cots in a draw-twisting machine, the shape of an arbitrary package is replaced with a corresponding functional formula, and from that functional formula, the traverse width of the ring rail is calculated by a microcomputer every time the direction of movement of the ring rail is changed, and the traverse width of the ring rail is separately measured. A method for forming a cot tip, characterized in that the timing of raising and lowering the ring rail is measured in combination with the traverse width of the ring rail or the moving speed of the ring rail, and based on the results, an electric signal is generated to control the reciprocating movement of the ring rail.