WO1999029941A1

WO1999029941A1 - Alternate twisted yarn manufacturing method

Info

Publication number: WO1999029941A1
Application number: PCT/US1998/025939
Authority: WO
Inventors: Kazuyoshi Kida
Original assignee: Izumi International, Inc.
Priority date: 1997-12-10
Filing date: 1998-12-07
Publication date: 1999-06-17
Also published as: AU1630499A

Abstract

In a manufacturing method for alternate twisted yarn in which raw yarn (1) is drawn out continuously from supply bobbin (2), the raw yarn (1) thus drawn out is inserted and passed through twist spindle (6) that is repeating unidirectional intermittent rotation or clockwise and counter-clockwise intermittent rotation at given time intervals. The yarn sent out from the twist spindle (6) is wound on to the take-up bobbin (9). The twist spindle (6) is arranged adjacent to the take-up bobbin (9), and the yarn is wound on to the take-up bobbin (9) while a reciprocating motion is given to the take-up bobbin (9) at the stroke corresponding to its traverse width or, the yarn is wound on to the take-up bobbin (9) while a reciprocating motion is given to the traverse base on to which the twist spindle (6) is mounted at the stroke corresponding to the traverse width of the take-up bobbin (9).

Description

Alternate Twisted Yarn Manufacturing Method Background of the Invention

This invention relates to the method for manufacturing an alternate twisted yarn in which the Z twist area and S twist area alternately exist along the longitudinal direction of the yarn.

The example manufacturing method for alternate twisted yarn is shown in the Official Gazette of Patent OPI Publication 1996-246280 and the Specification in Patent Application 1997-155996 associated with the patent application by the applicant of this patent. The method disclosed in Official Gazette of Patent OPI Publication 1996-246280 is such that the raw yarn is drawn out continuously or intermittently from the supply bobbin (which is fixed) and the raw yarn thus drawn out is inserted and passed through the twist spindle rotating intermittently in one direction for intermittent twisting, which is then to be heat set after it is wound on to the take-up bobbin. Further, the method disclosed in the specification in Patent Application 1997-155996 is such that the raw yarn is drawn out of the supply bobbin and is inserted and passed through the twist spindle that is rotating alternately clockwise and counter clockwise at given time intervals, which twists the yarn in alternating directions thus periodically changing the direction of the twist on the yarn which is then wound on to the take-up bobbin.

The yarn wound around the take-up bobbin by the method described above becomes an alternate twisted yarn in which the Z twist area and S twist area exist alternately in the longitudinal direction of the yarn, and the shrink wrinkle processing texture with its unique feeling can be woven by using this alternate twisted yarn. According to the method of rotating the twist spindle clockwise and counter clockwise, an alternate twisted yarn with higher twist can be obtained, compared with the method of rotating the twist spindle intermittently in only one direction.

Figure 4 typically illustrates example equipment for manufacturing an alternate twisted yarn by the conventional method described above. Raw yarn 1 is drawn out in the axial direction from the supply bobbin 2 attached to the twisting machine frame with no rotation, which passes through yarn guide 4 and feed roller 5, and is inserted and passed through the twist spindle 6 that is rotating intermittently or in reverse at given time intervals, and the twist yarn 13 thus passing through the twist spindle 6 is wound on to the take-up bobbin 9 via feed roller 8 and traverse mechanism 12. Traverse mechanism 12 has different types of structures; for example, as shown in Figure 4, this structure is such that yarn guide 16 is fixed to the traverse shaft 11a located in parallel to drive drum 14 which rotates and drives the take-up bobbin 9. The twisted yarn 13 is wound on to the take-up bobbin 9 at the predetermined winding width by giving reciprocating motion in the axial direction to the traverse shaft 11a with a cam and pulse motor or the like. Further, the take-up bobbin 9 is of a structure rotated and driven by drive drum 14 that rotates adjacent to the outer circumference of wound yarn (surface driven) , and twisted yarn 13 is wound at a constant speed regardless of the diameter of take-up bobbin 9.

Summary of the Invention Regarding the method of manufacturing an alternate twisted yarn in which the Z-and S-twist areas exist alternately along the longitudinal direction of the yarn, the technical method of reducing the length of the transition area existing in the twisting inversion portion is obtained.

Since the Z-twist area and S-twist area exist alternately in the longitudinal direction of the yarn in the alternate twisted yarn, there exists a virtually non-twisted transition area with a small number of twists between both the Z-twist and S-twist areas. Generally speaking, depending on the application of the alternate twisted yarn, it is more preferable that this transition area be short. In particular, when an attempt is made to form more Z and S twist areas alternately at short intervals, it is essential to make the transition area short.

In the conventional method, a problem exists in which there arises a transition area with considerable length such that higher twisting cannot be applied alternately at short intervals. Another problem is also manifested in that there is a limit to the sharp feeling given to the shrink wrinkle processing texture since the twisting direction changes slowly in the transition area. This invention is, therefore, directed to obtaining a technical means of being able to reduce the length of the transition area that exists in the portion where alternate twisted yarn twisting is inverted.

The alternate twisted yarn manufacturing method in this invention is such that raw yarn 1 is pulled out continuously from the supply bobbin 2. The raw yarn 1 thus pulled out, is inserted and passed through twist spindle 6 that repeats unidirectional intermittent rotation or reverse rotation at given time intervals, and the yarn delivered from the twist spindle 6 is wound on to the take-up bobbin 9. In the invention in claim 1, the twist spindle 6 is arranged adjacent to the take-up bobbin 9, and the yarn is wound while reciprocating motion is being given to the take- up bobbin 9 at the stroke corresponding to its winding-up width. On the other hand, in the invention disclosed in claim 2, the twist spindle 6 is mounted on the traverse base 11 arranged adjacent to the take-up bobbin 9, thus winding the yarn while giving reciprocating motion to the traverse base 11 at the stroke corresponding to the take-up bobbin 9 winding-up width.

When a yarn is twisted with the twist spindle 6 arranged between the supply bobbin 2 and take-up bobbin 9, the yarn will be twisted on the twist spindle against itself on the upstream side (supply bobbin side) and the downstream (take-up bobbin side) in the reverse direction. If the yarn is stopped, the number of yarn twists on the upstream and downstream sides will increase in proportion to the twist spindle revolutions. If the yarn is travelling, however, the twisting on the downstream side is wound on to the take- up bobbin 9, which is fixed, but on the upstream side, the length of yarn that is sent to the downstream side passing through the twist spindle will be untwisted.

If the twist spindle 6 is rotated continuously in one direction, the yarn wound up shortly after the rotation starts will be twisted, but the number of twists decreases soon thereafter and then non-twisted yarn will be wound up. This indicates the condition in which the yarn twisted on the downstream side by the twist spindle is countervailed by twisting in the reverse direction approaching the downstream side from the upstream side. If the twist spindle 6 is rotated intermittently in one direction, the twisting in the reverse direction on the upstream side is sent to the downstream side through the stopped twist spindle, which is wound on to the take-up bobbin 9 and fixed, so that the yarn thus wound onto the take-up bobbin 9 turns into an alternate twisted yarn in which both S and Z twist areas appear alternately in the longitudinal direction of the yarn. If the twist spindle 6 is rotated alternately in the clockwise and the counter clockwise directions, the twisted yarn sent to the downstream side from the upstream side when the twist spindle rotation is reversed, will be accelerated by means of the twist spindle inversion. This will cause the transition area to be shorter than it would be if the twist spindle were rotated intermittently in one direction. By alternating the direction of the twist spindle it is also possible to obtain an alternate twisted yarn with a higher twist in each area

To obtain an alternate twisted yarn, whose transition area is short, the twisting may be fixed by winding the yarn on the downstream side of twist spindle 6 as quickly as possible. For this purpose, it is effective to reduce the length of the downstream-side yarn between twist spindle 6 and take-up bobbin 9. To wind the yarn on to the take-up bobbin 9, however, a traverse mechanism for giving traverse motion to the yarn is indispensable. Further, since the yarn is traversing at an angle by the traverse mechanism, it is impossible to significantly reduce the spacing between traverse mechanism 12 and feed roller 8 shown in Figure 4. If this distance is made short, the yarn traverse angle from the feed roller will become large, thereby causing increased tension fluctuations. The method in this invention makes it possible to wind the yarn on to the take-up bobbin 9 without providing a traverse mechanism by giving reciprocating motion in the axial direction to the take-up bobbin 9 (Invention in Claim 1) or, allow the twist spindle 6 to share the traverse mechanism function by giving reciprocating motion to the twist spindle 6 itself (Invention in Claim 2) . Therefore, it is possible to arrange the twist spindle 6 very close to the take-up bobbin, making the length of the transition area on the alternate twisted yarn extremely short. Brief Description of the Drawings

Figure 1 is an oblique drawing typically showing the embodiment of the invention in Claim 1. Figure 2 is an oblique drawing typically showing the embodiment of the invention in Claim 2.

Figure 3 is a cross -sectional drawing showing a sample twist spindles.

Figure 4 is a typical oblique drawing for conventional alternate twisted yarn manufacturing Method.

Description of the Preferred Embodiment

Figure 1 is the first embodiment of the invention. The take-up bobbin 9 is equipped with a flange 9a at both ends. Both ends are supported with bearings on both sides at the edge of the cradle 17 with the support shaft 19 as an oscillation center, which is vertically movable. The bearing unit on both sides at the edge of cradle 17 is of a flexible structure so that it opens slightly to the outside in order to facilitate removal and re-installation of take- up bobbin 9. The driving drum 14 supports the outer circumference of the wound yarn in the state in which it is fitted between the flanges 9a of take-up bobbin 9. The drive drum 14 is fixed to the drive shaft 15, which rotates at a constant speed. The drive shaft 15, in addition to the above-mentioned motion, reciprocally moves in its axial direction together with support shaft 19 simultaneously on the given cycle. The stroke of this reciprocating movement determines the traverse width of take-up bobbin 9. The twist spindle 6 is pivotally secured to bracket 18 fixed to the twisting machine frame, which is arranged in the fixed position close to the take-up bobbin 9 and drive drum 14 (the contact point through which the twisted yarn passes) . Since the yarn thus twisted by twist spindle 6 is immediately wound on to the take-up bobbin 9, it is possible to greatly reduce the length of the transition area that occurs during the twist spindle 6's rotation, stop or reverse rotation. For example, when the travelling distance of the yarn between twist spindle 6 and take-up bobbin 9 is set to 3 centimeters, the actual length for the transition area can be 1 to 2 centimeters.

Figure 2 shows the second embodiment of this invention. In this second embodiment, the take-up bobbin 9 and drive drum 14 do not make a reciprocating motion in the axial direction. The traverse base 11 is arranged in parallel to the shaft of take-up bobbin 9 and drive roller 14, and a reciprocating motion is given to this traverse base 11 in the axial direction at the stroke corresponding to the take-up bobbin 9 traverse width. The twist spindle 6 is pivotally secured to the bracket 18a and is fixed to the traverse base 11, which is placed adjacent to the position where the take-up bobbin 9 and drive roller 14 come into contact with each other. In this second embodiment, the twist spindle 6 is reciprocated in the axial direction of take-up bobbin 9 by giving a reciprocating motion to the traverse base 11, thus giving a traverse motion to the yarn wound onto the take-up bobbin 9.

The twist spindle 6 as shown in Figure 3, is provided with support shaft 22 inclined to the inside of cylindrical body 21. The grooved pulley 24 equipped with U- or V-groove 23 for wrapping the yarn on the outer circumference is pivotally secured in the center of this support shaft. The cylindrical body is shaft supported with a bearing (not illustrated) on its outer circumference side, which is coupled to the rotary drive source that can be rotated clockwise and counter clockwise. This rotary drive source can be an electrical motor and/or an air motor. When the method in the above-mentioned second embodiment in particular is employed, the inertial load required for giving a reciprocating motion to the twisting device 6a can be reduced by adapting the structure for rotating the twist spindle 6 with an air motor. Since the traverse speed of the yarn to be wound is not so high for the twisting machine, there is no problem in the twisting machine even when an electric motor is employed. Further, the support shaft 22 that bears the grooved pulley 24 of the twist spindle is offset from the center of cylindrical body 21 by the distance nearly equal to the radius of grooved pulley 24 so that the pullout end of the yarn set over the groove 23 of the grooved pulley falls on the center shaft line of cylindrical body 21.

The twist spindle 6 is arranged with the center shaft of cylindrical body 21 matched with the yarn passage line. The yarn 13 is inserted into the cylindrical body 21 and is wrapped around the grooved pulley 24 only once, which is drawn out from the opposite side. Since the grooved pulley 24 is secured to the inclined support shaft 22, both ends of the yarn wrapped around the grooved pulley are drawn out from the groove 23, whereby the yarn entering the grooved pulley 24 does not contact the yarn exiting the grooved pulley. By using such a grooved pulley, it is possible to avoid the problem where the yarn on the entrance side and the exit side of the pulley rub each other. In particular, when a stronger twist is applied to the yarn on the entrance side and makes contact with the untwisted yarn on the exit side this will generate fluff or cause entanglement thus causing yarn breakage.

Description of Reference Numerals

1 Raw yarn

2 Supply bobbin 6 Twist spindle Take-up bobbin Traverse base

Claims

CLAIMSWhat is claimed is:

1. An alternate twisted yarn manufacturing method, comprising: providing a supply bobbin of raw yarn and substantially continuously drawing said raw yarn out of said supply bobbin; providing a twist spindle which repeats unidirectional intermittent rotation or reverse rotation at predetermined time intervals; inserting said raw yarn drawn from said supply bobbin into said twist spindle and passing said raw yarn therethrough; providing a take-up bobbin defining a winding width and winding said raw yarn from said twist spindle on said take-up bobbin; providing said twist spindle adjacent to said take-up bobbin; and winding said raw yarn on said take-up bobbin while giving reciprocating motion to said take-up bobbin at a stroke corresponding to said winding width of said take-up bobbin.

2. An alternate twisted yarn manufacturing method, comprising: providing a supply bobbin of raw yarn and substantially continuously drawing said raw yarn out of said supply bobbin; providing a twist spindle which repeats unidirectional intermittent rotation or reverse rotation at predetermined time intervals; inserting said raw yarn drawn from said supply bobbin into said twist spindle and passing said raw yarn therethrough; providing a take-up bobbin defining a winding width and winding said raw yarn from said twist spindle on said take-up bobbin; providing a traverse base and positioning said traverse base adjacent to said take-up bobbin; mounting said twist spindle on said traverse base; and winding said raw yarn while giving reciprocating motion to said traverse base at a stroke corresponding to said winding width of said take-up bobbin.