JPS6133472A - Adjusting of string tension - Google Patents

Abstract

PURPOSE:To automatically adjust the tension of string uniformly from the start to the end of winding by rotating a rotary member with which the circumference of string will contact with such circumferential speed as higher than the travelling speed of string in the travelling direction while sliding the string through the contacting section with the rotary member. CONSTITUTION:The string Y released from a string feed body 1 is led through a guide 2 to tension setting guide 3 and contacted against the circumferential face of rotary member 4. Then it is passed through a tension setting guide 5 to be traversed with predetermined amplitude through a traverse guide 6 and wound over a winding member 7. Here, the rotary member 4 is rotated in the travelling direction with higher circumferential speed than the travelling speed of the string Y thus to travel the string Y while sliding against the circumferential face of the rotary member 4. The initial specified tension is selected to desired level through adjusting of the contacting angle theta of the string Y against the rotary member 4 due to the motion of said guides 3, 5 or the rotation of the rotary member 4. Consequently, the tension of the string Y can be automatically adjusted uniformly from the start to the end of winding.

Description

Detailed Description of the Invention [Technical Field of the Invention] The present invention is directed to applying the tension of a yarn that is continuously wound onto a winding body while being unwound from a yarn supply body to the winding body. This invention relates to a yarn tension adjustment method that can automatically adjust the tension almost uniformly from the beginning of winding to the end of winding.

[Prior art]

When the yarn unwound from the yarn supplying body is continuously wound onto the winding body, the winding of the yarn increases as the number of yarn layers wound on the winding body increases (the diameter of the winding body increases). As the speed increases, the unwinding speed increases as the yarn layer of the yarn feeder gradually decreases, making it more likely that abnormal tension will occur in the yarn that is continuously unwound from the yarn feeder. The thread layer of the body undergoes a change in hardness, with the inner layer being soft and the outer layer being hard, which can cause the thread layer to collapse, making it difficult to make large packages. In order to solve this problem, it is possible to gradually lower the winding speed or to amplify the initial tension to match the tension at the end of winding, but neither of these methods is practical and still remains. No effective solution has yet been found.

In addition, in shuttleless looms that use fluid injection to insert weft yarns, the weft yarns unwound from the yarn feeder are measured to a specified length and temporarily stored in the length measuring device due to intermittent weft insertion. However, if the unwinding tension fluctuates in the weft yarn being unwound from the yarn supplier, accurate length measurement may not be possible and the inserted length may be incorrect. Since the weft becomes uniform, there is a problem that the weft insertion trouble occurs and the frequency of stopping of the loom increases. In order to solve this problem, it may be possible to adjust the length measurement to the length at the highest level of unwinding tension, but in this case, the length measurement becomes longer than necessary at the initial tension of unwinding. However, there are problems such as causing stoppage factors other than weft insertion troubles and leading to weft loss, and no effective solution has been found yet.

[Purpose of the invention]

In view of the conventional problems as described above, an object of the present invention is to reduce the tension of a yarn that is continuously wound onto a winding body while being unwound from a yarn supplying body. It is an object of the present invention to provide a method for automatically adjusting yarn tension almost uniformly from the beginning to the end of winding.

[Structure of the invention]

The thread tension adjustment method of the present invention that achieves the above object is such that when the yarn is unwound from the yarn supplying body and continuously wound onto the winding body, there is a gap between the yarn supplying body and the winding body. , a rotating body is provided with which the yarn comes into contact with the circumferential surface, and the rotating body is rotated at a circumferential speed higher than the running speed of the yarn in the running direction, so that the yarn comes into contact with the rotating body. It is characterized by sliding.

[Embodiments of the invention]

Next, the present invention will be described in detail with reference to the drawings.

FIG. 1 shows a first embodiment, in which the present invention is applied to the process of sequentially joining yarns from a yarn feeder and winding them into a winding body to form a sillage package. FIG.

The yarn Y unwound from the yarn supplying body 1 passes through the guide 2, enters the tension setting guide 3, comes into contact with the circumferential surface of the rotating drum 4, which is a rotating body, and then passes through the tension setting guide 5.
A traverse of a predetermined width is given by a traverse guide 6, and the material is wound onto a winding body 7. The most important point here is to rotate the rotating drum 4 at a circumferential speed higher than the running speed of the yarn Y in the running direction so that the yarn Y runs while sliding on the drum circumferential surface. 1. In this respect, the function of the drum 4 is completely different from that of a conventional feed roller.

The number of revolutions of the winding body 7 is constant, and the diameter of the winding body 7 changes (increasing force h) from the beginning of winding the yarn (indicated by a dotted line) to the end of winding (indicated by a solid line). As the winding speed increases, the unwinding speed of the yarn from the yarn supplying body 1 increases, and the unwinding tension increases as the yarn layer of the yarn supplying body gradually decreases. Therefore, in this case, the contact pressure of the contact portion of the yarn Y with the rotating drum 4, especially the contact portion A on the inlet side, is strengthened, and the rotating drum 4 (as described above, this rotating drum 4 is Since the rotational force of the yarn Y (which is rotating at a circumferential speed of
The amount of yarn supplied to the machine increases. As a result, the winding tension on the winding body 7 decreases and is maintained at the initially specified tension. In addition, when the yarn in the yarn feeder 1 runs out and is replaced with a new yarn feeder and the winding tension falls below the initial specified tension, the contact portion of the yarn Y with the rotating drum 4, especially the contact portion B on the exit side. (In this case, the contact pressure on the contact part on the inlet side is eased by the decrease in the unwinding tension from the yarn supplying body), and the yarn runs while removing the yarn from the drum surface. In order to
The amount of yarn supplied to the winding body 7 is reduced. As a result, the winding tension on the winding body 7 increases and is maintained at the initially specified tension. In this way, the tension of the yarn Y, which is unwound from the yarn supplying body 1 and continuously wound onto the winding body 7, can be automatically adjusted to be substantially uniform from the beginning of winding to the end of winding.

Note that the initial specified tension can be adjusted by increasing or decreasing the contact angle θ of the yarn with the rotating drum 4 due to movement of the tension setting guide 6.5;
A desired tension can be selected by adjusting the rotation speed of the rotating drum 4, etc.

FIG. 2 shows a second embodiment, and is a side view showing an embodiment in which the present invention is applied to a process of feeding yarn (weft) from a yarn feeder to a length measuring device in a shuttleless loom. It is.

The yarn Y unwound from the yarn supplying body 1 passes through the guide 2, enters the tension setting guide 3, comes into contact with the circumferential surface of the rotating drum 4, which is a rotating body, and then passes through the tension setting guide 5.
It is led to the length measuring device 8 via the length measuring section guide 6'. Also in this case, when the unwinding tension from the yarn supply body 1 increases, the yarn Y
The contact pressure at the contact portion with the rotating drum 4 is strengthened, the amount of yarn supplied to the length measuring device 8 is increased, and the initially specified tension to the length measuring device 8 is maintained. Further, the tension adjustment when the unwinding tension is lowered from the yarn supplying body 1, the selection of the initial specified tension, etc. are the same as in the first embodiment.

Note that the configuration, usage conditions, etc. of the rotating body used in implementing the present invention, that is, the rotating drum 4 in each of the above embodiments, can be selected as follows.

(1) The rotating drum 4 can be rotated by direct drive of a motor or can be rotated from a machine via a drive system.

(2) The rotating drum 4 can be surface-treated to obtain a desired rubbing effect with the yarn. The surface treatment can be performed by, for example, hard chrome coating, hard matte plating, hard rubber treatment, alumina material treatment (alumina explosion bonding), coating with metal to increase Vickers hardness, etc.

(3) The rotating drum 4 must be rotated at a circumferential speed higher than the yarn traveling speed and in the traveling direction. The rotation speed is selected taking into account the quality of the yarn running on the drum surface, the running speed, the sliding force with the drum surface (relationship with the rotating drum material, surface treatment, etc.), etc. The ratio of the circumferential speed of the drum 4/the speed of the yarn running on the surface of the drum is 1 to 2
It is preferable to set it as the range of.

(4) The rotating drum 4 is linked to stopping and restarting the machine. Therefore, there is no problem with the unwinding tension when the machine is stopped and restarted.

(5) The use of the rotating drum 4 is not limited to one as in the above embodiment, but a combination of a plurality of drums may also be used.

Incidentally, FIG. 3 shows an embodiment of a rotating body directly driven by a motor consisting of a combination of two rotating drums, including a lower rotating drum 4a and an upper rotating drum 4b. 4a is directly connected to and driven by a motor M that can continuously change the number of revolutions, and the upper rotating drum 4b is interlocked by the meshing of gears G+ and G2.

This rotating body unit is attached to a desired location on a loom or the like using an attachment member 9. Each rotating drum 4a.

4b has circumferential grooves S, S2 with a U-shaped cross section,
The yarn Y unwound from a yarn feeder (not shown) meanderingly passes through the circumferential grooves 5l-82 of both rotating drums 4a and 4b.
It slides inside and is supplied to a winding body (not shown). In addition, in the rotating body of this embodiment, since the yarn Y is meandering, each rotating drum 4a.

The yarn Y is securely brought into contact with the yarn 4b, and therefore the tension setting guide as in each of the embodiments described above can be omitted.

Next, the present invention will be specifically explained using examples.

EXAMPLE The rotating body shown in FIG. 3 was installed between the yarn feeder and length measuring device of the following shuttleless loom, and weaving was carried out under the following conditions.

Loom used: Water jet loom LW-52-
T4-150 (manufactured by Nissan Motor Co., Ltd.) Loom rotation speed: 520 rpm Weaving width: 132 cIIL Yarn used (weft): Polyester false twisted yarn 75 d (7
5/2 → First twist 750 t/m → False twist → Additional twist 1500 t/m) Yarn feeding and unwinding speed: 377 m/min (2 synthetic fibers) Rotating drum 4a
, 4b: Main body, aluminum light alloy; peripheral part, ceramic;
Diameter: 120 L/rpm: 1 rotation L: 100 rpm This was compared with the case of not using the rotating body (conventional method) shown in Fig. 3, and the results were as shown in the table below.

(Left space on this page) (*) Operating efficiency indicates the ratio of actual operating time over a 24-hour period.

As is clear from the table, in the case of the conventional method, fluctuations in the unwinding tension occur in the yarn (weft) unwound from the yarn feeder, making it difficult to measure the length accurately, resulting in an incorrect weft-inserted length. The problem of uniform weft insertion increases the number of stops of the loom, increases the rate of weft loss, and reduces operating efficiency.In contrast, with the method of the present invention, tension adjustment is performed efficiently and the loom improves. Both the number of stops and the incidence of weft loss were extremely low, and the operating efficiency was excellent.

〔Effect of the invention〕

As described above, in the yarn tension adjustment method of the present invention, when the yarn is unwound from the yarn supplying body and continuously wound onto the winding body, there is a gap between the yarn supplying body and the winding body. , Providing a rotating body with which the yarn comes into contact with the circumferential surface, and rotating the rotating body at a circumferential speed higher than the running speed of the yarn and in the running direction to bring the yarn into contact with the rotating body. Since the structure is such that the thread is slid on the winding body, the tension of the yarn that is unwound from the yarn feeder and continuously wound onto the winding body is controlled from the beginning of winding on the winding body to the winding end. It can be automatically adjusted almost uniformly. Therefore, by applying the present invention to the yarn large packaging process,
It is possible to efficiently form a yarn layer with almost uniform hardness in the inner and outer layers without fear of deformation, and the present invention can be applied to one step of feeding yarn to a length measuring device in a shuttleless loom. As a result, accurate length measurements can be made and weaving efficiency can be significantly improved. Further, the rotating body used in carrying out the present invention is rotated at a circumferential speed higher than the running speed of the yarn and in the running direction, so that the yarn runs while sliding on the circumferential surface of the rotating body. Its function is completely different from that of conventional feed rollers in that it is designed to do this, and by simply installing such a rotating body between the yarn feeder and the winder, the tension of the yarn can be adjusted automatically. It is easy to operate and handle.

[Brief explanation of the drawing]

The figure shows an embodiment of the present invention, and Fig. 1 shows a state in which the tension of the yarn is adjusted in the process of sequentially joining the yarn from the yarn supplying body and winding it onto a winding body to form a large package. Figure 2 is a side view showing the state in which the tension of the yarn is being adjusted in the process of feeding the yarn from the yarn feeder to the length measuring device in a shuttleless loom, Figure 3, ) shows an example of a rotating body used in the implementation of the present invention, in which the figure shows a front view with a portion cut away, and the figure (■) shows a side view. 1... Yarn feeder, 4, 4a, 4b... Rotating body (
(rotating drum), 7... winding body, 8... winding body (length measuring device), Y... thread. Figure 1 (A) Figure 3 (B)

Claims (1)

[Claims] When unwinding the yarn from the yarn supplying body and continuously winding it onto the winding body, a rotating body is provided between the yarn supplying body and the winding body, with which the yarn comes into contact with the peripheral surface. A method for adjusting the tension of a yarn, which comprises rotating the rotating body in the running direction at a circumferential speed higher than the running speed of the yarn, and causing the yarn to slide at a contact portion with the rotating body.