EP2671834A2

EP2671834A2 - Yarn winding device

Info

Publication number: EP2671834A2
Application number: EP13170641.8A
Authority: EP
Inventors: Shotaro Okugawa
Original assignee: Murata Machinery Ltd
Current assignee: Murata Machinery Ltd
Priority date: 2012-06-08
Filing date: 2013-06-05
Publication date: 2013-12-11
Also published as: CN103482413A; EP2671834A3; JP2013252966A

Abstract

A yarn winding device includes a yarn directing mechanism (71) that, when a yarn (Y) is cut, moves a yarn end (YB) from a package (P) toward the center of an outer peripheral surface of the package (P). The yarn directing mechanism (71) includes jet nozzles (72) that are oriented from a downstream side of a contact portion (C) between the outer peripheral surface of the package (P) and the outer peripheral surface of a winding roller (23) in a winding and rotating direction of the winding roller (23) and also from both ends of the winding roller (23) toward the center of a contact portion (C) between the outer peripheral surface of the package (P) and an outer peripheral surface of a winding roller (23) in a longitudinal direction. Most Illustrative Drawing: FIG. 3A

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a yarn winding device that winds a yarn on a winding bobbin to form a package.

2. Description of the Related Art

In a yarn winding apparatus, such as, a spinning machine or a winder, a cutter cuts the yarn when a yarn defect detecting section (yarn clearer) detects a defective portion in a yarn during formation of a package. Because the package keeps spinning due to inertia even after the yarn has been cut by the cutter, a yarn end from the package is wound and stays on the package. The yarn end, however, may not be wound on the package and be hanging down from the outer peripheral surface of the package. Such a state is "end missing".
When the end missing occurs, the yarn end cannot be found in performing yarn joining, leading to reduced operation efficiency of the yarn winding apparatus. Furthermore, fuzzing can occur in the package in the process of finding the yarn end in the end missing state, leading to a drop in the quality of the package.
Even if end missing has not occurred, the location of the yarn end wound around the peripheral surface of the package can vary. For example, the yarn end could be located near the center of the outer peripheral surface or could be located near one of the ends of the outer peripheral surface. Because the position of the yarn end on the outer peripheral surface of the package is indeterminate, a suction member that finds the yarn end from the package during yarn joining should be able to suck and catch the yarn end wherever the yarn is. Consequently, with the conventional technologies, a width of a suction vent of the suction member has to be made greater than a width of the outer peripheral surface of the package.
However, more air is sucked by the wider suction vent of the suction member, and to produce an air current that is necessary to suck and catch the yarn end with the wider suction vent, a larger and high-power negative pressure source is used. Consequently, the conventional yarn winding apparatus consumes a large amount of energy for sucking and catching just one end of a yarn.
As a solution to the above problem, a yarn winding device having jet nozzles for ejecting compressed air from both ends of an axial direction of the package forward and toward the center of the package has been suggested (see, for example, Japanese Patent Application Laid-open No. H3-42468 ). In the yarn winding device disclosed in Japanese Patent Application Laid-open No. H3-42468 , the compressed air is ejected before the cut yarn end is wound on the package to prevent the end missing and also to move the yarn end to a position near the center of the outer peripheral surface of the package.
However, the duration from the time point when the yarn is cut to the time point when the yarn end is wound on the package is extremely short. Even assuming that compressed air is ejected through the jet nozzles at the same time the yarn is cut, extremely short time is available for the compressed air to act on the yarn. It is therefore difficult, even if the compressed air is ejected toward the yarn that is being wound, to reliably prevent the end missing from occurring and also to reliably move the yarn end toward the center of the outer peripheral surface of the package.

SUMMARY OF THE INVENTION

The present invention has been made in view of the problems described above. One object of the present invention is to provide a yarn winding device that can reliably prevent end missing from occurring, and also that can move the yarn end to a position near the center of the outer peripheral surface of the package. Another object of the present invention is to provide a yarn winding device that requires less power for a suction member to suck and catch the yarn end.
The problems that the present invention has been made to solve have been explained above. The means to solve those problems are explained below.
A yarn winding device that forms a package according to an aspect of the present invention includes a winding roller that rotates in contact with the package and assists in winding of the package; a cradle that rotatably supports the package and that is swingable in a contacting direction in which the package comes into contact with the winding roller, and a separating direction in which the package is separated from the winding roller; a driving mechanism that drives the cradle in the contacting direction and the separating direction; a braking mechanism that brakes rotation of the package; and a yarn directing mechanism that, when a yarn is cut, causes a yarn end to move from the package toward a center of an outer peripheral surface of the package by an action of air currents, wherein the yarn directing mechanism includes jet nozzles that eject compressed air and that are arranged at positions that are on a downstream side of a contact portion between the outer peripheral surface of the package and an outer peripheral surface of the winding roller in a winding and rotating direction of the winding roller and at both ends of the outer peripheral surface of the winding roller, and the jet nozzles are arranged so that jet vents thereof are oriented toward center of the contact portion between the outer peripheral surface of the package and the outer peripheral surface of the winding roller in a longitudinal direction.
The above and other objects, features, advantages and the technical and industrial significance of this invention will be better understood by reading the following detailed description of presently preferred embodiments of the invention, when considered in connection with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a simplified front-view diagram of a yarn winding device according to an embodiment of the present invention;
FIG. 2 is a block diagram of main circuits of the yarn winding device;
FIG. 3A is a side view of a package and a winding roller showing a state in which a yarn is being wound;
FIG. 3B is a plan view of the package from above;
FIG. 4A is a side view of the package and the winding roller showing a state in which the package has been lifted and a yarn directing mechanism is in action;
FIG. 4B is a plan view of the package from above;
FIG. 5A is a front view showing a state in which a suction member according to the embodiment is in close proximity to the package;
FIG. 5B is a front view showing a state in which a conventional suction member is in close proximity to the package; and
FIG. 6 is a timing chart showing operations of the yarn winding device before and after a yarn is cut.

DETAILED DESCRIPTION OF EMBODIMENTS

Exemplary embodiments of the present invention are explained in detail below with reference to the accompanying drawings.
A yarn winding device 11 according to a first embodiment of the present invention is explained with reference to FIGS. 1 to 6.
First, an overall structure of the yarn winding device 11 is explained. As shown in FIG. 1, the yarn winding device 11 unwinds a yarn Y from a supply bobbin 91 and traverses the yarn Y with a winding roller 23 thereby forming yarn layers on a winding bobbin B to form a package P. A running direction of the yarn Y is from the supply bobbin 91 toward the package P. The yarn winding device 11 shown in FIG. 1 is a single unit. A yarn winding apparatus (automatic winder) is formed by arranging a plurality of such yarn winding devices 11 side by side. In the explanation given below, the winding bobbin B and the package P in which the yarn layers are formed on the winding bobbin B are collectively referred to as the package P.
As shown in FIGS. 1, 3A, and 3B, the yarn winding device 11 includes a winding section 21, a yarn supplying section 31, and a yarn directing mechanism 71.
The winding section 21 winds the yarn Y to form the package P. The winding section 21 includes a cradle 22 and the winding roller 23. The cradle 22 rotatably supports the package P. The cradle 22 swings in a contacting direction causing the package P to come into contact with the winding roller 23, and swings in a separating direction causing the package P to separate from the winding roller 23. As the yarn Y is wound around the winding bobbin B, the diameter of the package P increases, and the cradle 22 swings. Consequently, an appropriate degree of contact is maintained between an outer peripheral surface of the package P and an outer peripheral surface of the winding roller 23.
A lift cylinder 24 is coupled to the cradle 22. The lift cylinder 24 is a driving mechanism that drives the cradle 22 to move in the contacting direction and in the separating direction relative to the winding roller 23. The lift cylinder (driving mechanism) 24 lifts the cradle 22 and thereby separates the outer peripheral surface of the package P from the outer peripheral surface of the winding roller 23.
The cradle 22 has bearings 25. The winding bobbin B is removably attached to the bearings 25 and is rotatably supported by the bearings 25 at both ends thereof. A package brake 26 (refer to FIG. 2), which is a brake mechanism that brakes the rotation of the package P, is built into the bearings 25. When the cradle 22 is lifted to separate the outer peripheral surface of the package P from the outer peripheral surface of the winding roller 23, the package brake (brake mechanism) 26 brakes and stops the rotation of the package P.
The winding roller 23 according to the present embodiment is a traverse drum and has a function of traversing the yarn Y in an axial direction of the package P (traversing function) and rotating the package P (rotational driving function). The winding roller 23 is arranged so that its outer peripheral surface is in contact with the outer peripheral surface of the package P. A winding roller driving motor (driving source) 27 is connected to the winding roller 23. By rotating while in contact with the outer peripheral surface of the package P, the winding roller 23 causes the package P to rotate accordingly. Traverse grooves 28 are formed on the surface of the winding roller 23. The yarn Y is wound on the package P while traversing the traverse grooves 28.
The yarn supplying section 31 supplies the yarn Y to be wound on the winding bobbin B. The yarn supplying section 31 includes a supply bobbin holding peg (not shown), and the supply bobbin 91 is mounted on the supply bobbin holding peg. A tension applying device 41, a yarn joining device 42, a yarn speed sensor 43, and a yarn clearer 44 are arranged on a yarn running path, in this order from the yarn supplying section 31 side, between the yarn supplying section 31 and the winding roller 23.
The tension applying device 41 applies appropriate tension to the yarn Y. The yarn clearer 44 detects yarn defects, such as a slub, by detecting by a sensor a thickness of the yarn Y that passes through a detecting section and analyzing by an analyzer (not shown) signals obtained from the sensor. The yarn clearer 44 can also be configured to detect a presence/absence of a foreign matter in the yarn Y in addition to an abnormality in the thickness of the yarn Y. The yarn clearer 44 cuts the yarn Y upon detection of a yarn defect (clearer cut). If no yarn defect is found but a traverse failure is found, the yarn clearer 44 cuts the yarn Y to stop the winding (additional cut). For this reason, a cutter 45 is attached to the yarn clearer 44.
When the yarn Y is cut by the yarn clearer 44 or when the yarn Y from the supply bobbin 91 runs out, the yarn joining device 42 joins a lower yarn end YA from the supply bobbin 91 and an upper yarn end YB from the package P. The yarn speed sensor 43 detects a running speed (yarn speed) of the yarn Y in a non-contact manner.
A suction pipe 51 is arranged below the yarn joining device 42 (on an upstream side of the running direction of the yarn Y). The suction pipe 51 catches by suction the yarn end YA from the supply bobbin 91 and guides the caught yarn end to the yarn joining device 42. A suction member 61 is arranged above the yarn joining device 42 (on a downstream side of the running direction of the yarn Y). The suction member 61 catches by suction the yarn end YB from the package P side and guides it to the yarn joining device 42. The suction pipe 51 is shaped into a pipe and is pivotable up and down about a shaft 52. A suction vent 53 is arranged at the leading end of the suction pipe 51. The suction member 61 is also shaped into a pipe and is pivotable up and down about a shaft 62. A suction vent 63 is arranged at the leading end of the suction member 61. A not-shown negative-pressure source is coupled to the suction pipe 51 and the suction member 61. The negative-pressure source produces a suctioning action at the suction vent 53 and the suction vent 63 at the leading ends.
The suction member 61 according to the present embodiment is explained below in detail. As shown in FIG. 5A, after the yarn Y is cut, the suction member 61 according to the present embodiment brings the suction vent 63 near the outer peripheral surface of the package P, upon which the suction vent 63 sucks and catches the yarn end YB that is located on the outer peripheral surface of the package P. The yarn joining is then performed with the caught yarn end. The suction vent 63 is a horizontal opening. Air currents for sucking in the yarn end YB are generated at the suction vent 63 by the not-shown negative-pressure source. As shown in FIG. 5A, in the present embodiment, a width LS1 of the suction vent 63 in the longitudinal direction is smaller than a width LP of the outer peripheral surface of the package P. Air is sucked in a central area in the width direction and a surrounding area SA1 of the central area on the outer peripheral surface of the package P.
On the other hand, as shown in FIG. 5B, in a conventional suction member 161, a width LS2 of a suction vent 163 in the longitudinal direction needs to be larger than the width LP of the outer peripheral surface of the package P. This is because the yarn end YB may be located at any position on the outer peripheral surface of the package P, sometimes near the center of the outer peripheral surface and sometimes near one of the ends of the outer peripheral surface (state shown in FIG. 5B). Because the position of the yarn end YB on the outer peripheral surface of the package P is indeterminate, it is necessary for the suction member 161, which finds the yarn end YB from the package P during yarn joining, to be able to suck and catch the yarn end YB wherever the yarn end YB may be located on the outer peripheral surface of the package P. Consequently, in the conventional suction member 161, the width LS2 of the suction vent 163 in the longitudinal direction is larger than the width LP of the outer peripheral surface of the package P. Therefore, the position where suction is applied on the outer peripheral surface of the package P spans the entire region SA2 of the outer peripheral surface of the package P.
The width LS1 of the suction vent 63 according to the present embodiment in the longitudinal direction is smaller than the width LP of the outer peripheral surface of the package P. This is because, when the yarn Y is cut, the yarn end YB from the package P is moved toward the center of the outer peripheral surface of the package P by the later-explained yarn directing mechanism 71. Consequently, although the suction vent 63 is narrower, the suction member 61 according to the present invention can reliably suck and catch the yarn end YB by application of suction to the central area and the surrounding area SA1 thereof of the outer peripheral surface of the package P in a width direction thereof.
As shown in FIGS. 3A and 3B, the yarn directing mechanism 71 moves the yarn end YB from the package P toward the center of the outer peripheral surface of the package P when the yarn Y is cut. The yarn directing mechanism 71 mainly includes a pair of jet nozzles 72, a pair of compressed air current channels 73, and a pair of valves 74.
The jet nozzles 72 eject compressed air. The jet nozzles 72 are connected to an air supply device (not shown) that is common to all the yarn winding devices 11 of the yarn winding apparatus (automatic winder) via the compressed air current channels 73 and the valves 74. The valves 74 are electro-magnetic valves that control the opening and closing of the compressed air current channels 73 upon receiving control signals.
As shown in FIG. 3A, the jet nozzles 72 are located on the downstream side of a contact portion C between the outer peripheral surface of the package P and the outer peripheral surface of the winding roller 23 in a winding and rotating direction of the winding roller 23, when viewed from the side. The winding and rotating direction of the winding roller 23 refers to the rotating direction of the winding roller 23 when the yarn Y is being wound around the package P. The winding and rotating direction of the winding roller 23 in FIG. 3A is in a counter-clock-wise direction. Furthermore, as shown FIG. 3B, the jet nozzles 72 are located on the two ends of the outer peripheral surface of the winding roller 23, when viewed from the top.
As shown in FIGS. 3A and 3B, the jet nozzles 72 are oriented from the two ends of the outer peripheral surface of the winding roller 23 toward the center of the contact portion C between the outer peripheral surface of the package P and the outer peripheral surface of the winding roller 23 in the longitudinal direction of the contact portion C. The jet nozzles 72 are oriented toward the outer peripheral surface of the winding roller 23.
The yarn directing mechanism 71 comes into operation and ejects compressed air from the jet nozzles 72 when the yarn Y is cut while the yarn Y is being wound (refer to FIGS. 3A and 3B). More specifically, the yarn directing mechanism 71 comes into operation and ejects compressed air from the jet nozzles 72 when the yarn Y is cut and the lift cylinder 24 separates the package P from the winding roller 23, and the package brake 26 brakes the rotation of the package P, as shown in FIGS. 4A and 4B.
The reason why the yarn directing mechanism 71 moves the yarn end YB from the package P toward the center of the outer peripheral surface of the package P is explained in detail.
First, if the yarn Y is cut while the yarn Y is being wound (refer to FIGS. 3A and 3B), the cradle 22 is lifted by the lift cylinder 2 so that the outer peripheral surface of the package P separates from the outer peripheral surface of the winding roller 23 (refer to FIGS. 4A and 4B). Thereafter, the package brake 26 comes into operation and brakes the rotation of the package P. Because the package P is rotating and winding the yarn Y at a considerably high speed until just before the package brake 26 comes into operation, the package P does not stop immediately and continues to rotate at a considerable speed by inertia even after the package brake 26 comes into operation. In this state, the yarn end YB from the package P does not adhere to the outer peripheral surface of the package P and sways owing to the centrifugal force generated by the inertial rotation of the package P. Consequently, the yarn end YB from the package P repeatedly hits and contacts the outer peripheral surface of the winding roller 23 until the package P comes to a stop.
Meanwhile, just before or substantially at the same time the cradle 22 is lifted, the yarn directing mechanism 71 starts the ejection of compressed air from the jet nozzles 72. The compressed air from the jet nozzles 72 forms strong air currents onto the outer peripheral surface of the winding roller 23. The air current direction is substantially the same as the directions in which the jet nozzles 72 are oriented. That is, the air current is oriented from the downstream side of the contact portion C between the outer peripheral surface of the package P and the outer peripheral surface of the winding roller 23 in the winding rotation direction of the winding roller 23 and also from both the ends of the outer peripheral surface of the winding roller 23 toward the central area of the contacting portion C between the outer peripheral surface of the package P and the outer peripheral surface of the winding roller 23 in the longitudinal direction.
Consequently, the yarn end YB from the package P that sways owing to the centrifugal force generated by the inertial rotation of the package P and repeatedly hits and contacts the outer peripheral surface of the winding roller 23 is moved toward the center of the package P by the repeated action of the strong air currents formed onto the outer peripheral surface of the winding roller 23.
Next, a structure that controls the operations of the yarn winding device 11 is explained. As shown in FIG. 2, a unit controller (controller) 81 that controls the yarn winding device 11 is arranged in the yarn winding device 11. The unit controller 81 is electrically connected to each section of the yarn winding device 11, and controls the operations of those sections. The unit controller 81 is connected to a machine controller 82. The machine controller 82 manages and controls one or more of the yarn winding devices 11 that form the automatic winder. The unit controller 81 receives signals from the sections of the yarn winding device 11 and controls the yarn directing mechanism 71 based on those signals. The unit controller 81 and the machine controller 82 include a CPU as a calculating section, and a ROM, a RAM, etc., as storage sections.
The operations of the yarn winding device 11 are explained below in greater detail.
As shown in FIG. 6, while the yarn Y is being wound, if the yarn clearer 44 detects a yarn defect, such as a slub, the yarn clearer 44 is turned "ON" (t21). The yarn clearer 44 then sends a control signal to the cutter 45 to cut the yarn Y. Upon receiving the control signals from the yarn clearer 44, the cutter 45 is turned "ON" (t22), and cuts the yarn Y. The yarn clearer 44 then sends a yarn defect detection signal and a yarn cut signal to the unit controller 81.
Meanwhile, upon receiving the yarn defect detection signal and the yarn cut signal from the yarn clearer 44, the unit controller 81 sends a control signal to the lift cylinder 24 to lift the cradle 22. Upon receiving the control signal from the unit controller 81, the lift cylinder 24 is turned "ON" (t23), and lifts the cradle 22.
Substantially at the same time the cradle 22 is lifted, the unit controller 81 sends a control signal to the package brake 26 to brake the rotation of the package P. Upon receiving the control signal from the unit controller 81, the package brake 26 is turned "ON" (t24), and brakes the rotation of the package P.
Just before or substantially at the same time the cradle 22 is lifted, the unit controller 81 sends a control signal to the yarn directing mechanism 71 to eject the compressed air. Upon receiving the control signal from the unit controller 81, the valve 74 is turned "ON" (t25), and the yarn directing mechanism 71 ejects the compressed air from the jet nozzles 72.
Just before the rotation of the package P comes to a stop, the unit controller 81 sends a control signal to the suction member 61 to suck and catch by the suction vent 63 the yarn end YB that is positioned on the outer peripheral surface of the package P. Upon receiving the control signal from the unit controller 81, the suction member 61 is turned "ON" (t26), the suction member 61 pivots so as to bring the suction vent 63 closer to the outer peripheral surface of the package P and sucks and catches the yarn end YB from the package P.
The above-explained yarn winding device 11 according to the present embodiment has the following advantages.
In the yarn winding device 11, when the yarn Y is cut, the lift cylinder 24 separates the package P and the winding roller 23, and the jet nozzles 72 of the yarn directing mechanism 71 eject the compressed air while the package brake 26 brakes the rotation of the package P. The yarn end YB from the package P, which is swaying owing to the centrifugal force generated by the inertial rotation of the package P, repeatedly hits and contacts the outer peripheral surface of the winding roller 23 until the package P comes to a stop. Consequently, the action of air currents of the compressed air can continue to be applied onto the yarn end YB passing through the gap between the outer peripheral surface of the package P and the outer peripheral surface of the winding roller 23 until the package P comes to a stop. Consequently, by reliable application of the action of the air currents of the compressed air on the yarn end YB, the missing of the yarn end YB can be reliably prevented, and the yarn end YB can be moved toward the center of the outer peripheral surface of the package P.
Moreover, because the jet nozzles 72 are oriented toward the outer peripheral surface of the winding roller 23, the yarn directing mechanism 71 forms strong air currents of the compressed air from the jet nozzles 72 toward the outer peripheral surface of the winding roller 23. Consequently, the action of the air currents of the compressed air can be reliably applied onto the yarn end YB from the package P that repeatedly hits and contacts the outer peripheral surface of the winding roller 23 by swaying owing to the centrifugal force generated by the inertial rotation of the package P. Thus, the missing of the yarn end YB can be reliably prevented, and the yarn end YB can be moved toward the center of the package P.
Furthermore, the width LS1 of the suction vent 63 of the suction member 61 in the longitudinal direction is smaller than the width LP of the outer peripheral surface of the package P, and therefore, air is sucked from the central area of the outer peripheral surface of the package P in the width direction. Because the yarn end YB from the package P has been moved toward the center of the outer peripheral surface of the package P by the action of the air currents of the compressed air from the jet nozzles 72 of the yarn directing mechanism 71, the yarn end YB can be reliably sucked and caught by the suction member 61, which sucks air in the central area of the outer peripheral surface of the package P in the width direction. Thus, the size of the suction vent 63 of the suction member 61 can be reduced, and a suction volume of the air can be reduced. Consequently, the energy required for sucking and catching the yarn end YB by the suction member 61 can be reduced.
Although the invention has been described with respect to specific embodiments, the present invention is not limited thereto, and various modifications can be made.
For example, in the yarn winding device 11 according to the above embodiment, the winding roller 23 is a traverse drum with the traverse grooves 28 formed on the roller surface, and, when the winding roller 23 is driven to rotate, the package P, which is subjected to a rotation force, is rotated. However, the structure is not limited thereto. For example, it is also possible to have a structure that includes a package driving source that drives the package P to rotate, a traversing device that traverses the yarn Y, and a second driving source that drives this traversing device. An arm-type mechanism or a belt-type mechanism can be accepted as the traversing device. In this case, the winding roller 23 will be a contact roller that is rotated by the rotation force received from the package P.
A yarn winding device that forms a package according to an aspect of the present invention includes a winding roller that rotates in contact with the package and assists in winding of the package; a cradle that rotatably supports the package and that is swingable in a contacting direction in which the package comes into contact with the winding roller, and a separating direction in which the package is separated from the winding roller; a driving mechanism that drives the cradle in the contacting direction and the separating direction; a braking mechanism that brakes rotation of the package; and a yarn directing mechanism that, when a yarn is cut, causes a yarn end to move from the package toward a center of an outer peripheral surface of the package by an action of air currents, wherein the yarn directing mechanism includes jet nozzles that eject compressed air and that are arranged at positions that are on a downstream side of a contact portion between the outer peripheral surface of the package and an outer peripheral surface of the winding roller in a winding and rotating direction of the winding roller and at both ends of the outer peripheral surface of the winding roller, and the jet nozzles are arranged so that jet vents thereof are oriented toward center of the contact portion between the outer peripheral surface of the package and the outer peripheral surface of the winding roller in a longitudinal direction.
In the yarn winding device according to the above aspect of the present invention, upon occurrence of a yarn breakage, the driving mechanism separates the package and the winding roller, and the yarn directing mechanism ejects compressed air through the jet nozzles while the braking mechanism is braking the rotation of the package. The yarn end from the package sways owing to the centrifugal force generated by the inertial rotation of the package, and repeatedly hits and contacts the outer peripheral surface of the winding roller until the package comes to a stop. Consequently, the air currents of the compressed air can be repeatedly applied onto the yarn end passing through a gap between the outer peripheral surface of the package and the outer peripheral surface of the winding roller until the package comes to a stop. By reliable application of the air currents of the compressed air onto the yarn end, the end missing can be reliably prevented, and the yarn end can be moved toward the center of the outer peripheral surface of the package. Furthermore, it is preferable that the jet nozzles be oriented toward the outer peripheral surface of the winding roller so that the yarn directing mechanism forms strong air currents of the compressed air from the jet nozzles toward the outer peripheral surface of the winding roller. Consequently, the air currents of the compressed air can be reliably applied onto the yarn end from the package, which sways owing to the centrifugal force generated by the inertial rotation of the package and repeatedly hits and contacts the outer peripheral surface of the winding roller. Thus, the end missing can be prevented, and the yarn end can be moved toward the center of the package.
The yarn winding device according to another aspect of the present invention further includes a controller that, when the yarn is cut, causes the driving mechanism to separate the package and the winding roller, the braking mechanism to brake the rotation of the package, and the yarn directing mechanism to eject the compressed air from the jet nozzles.
It is preferable that the controller operates the driving mechanism to separate the package and the winding roller, and the jet nozzles of the yarn directing mechanism eject compressed air while the package brake is braking the rotation of the package so that the yarn end does not become trapped between the package and the winding roller. This means that the yarn end can be moved toward the center of the package.
In the yarn winding device according to still another aspect of the present invention, the jet nozzles of the yarn directing mechanism are oriented toward the outer peripheral surface of the winding roller.
Because the jet nozzles are oriented toward the outer peripheral surface of the winding roller, the yarn layers on the package surface do not become disturbed by the compressed air that is ejected through the jet nozzles.
The yarn winding device according to still another aspect of the present invention further includes a driving source that produces a driving force, wherein the winding roller is a traverse drum with a traverse groove formed on a surface thereof and is driven by the driving source, and the package rotates upon receiving a force from the traverse drum.
The yarn winding device according to still another aspect of the present invention further includes a package driving source that produces a driving force; and a traversing device that traverses the yarn, wherein the winding roller is driven to rotate by a force received from the package.
The yarn winding device according to still another aspect of the present invention further includes a yarn joining device that joins ends of the yarn that has been cut; and a suction member that sucks and catches a yarn end from the package when the yarn joining device joins the yarn, wherein a width of a suction vent formed in the suction member in a longitudinal direction is smaller than a width of the outer peripheral surface of the package in a rotation axis direction, and the suction vent sucks air in a central area of the outer peripheral surface of the package in the rotation axis direction.
It is preferable that the width of the suction vent of the suction member in the longitudinal direction be smaller than the width of the outer peripheral surface of the package so that air can be sucked in the central area of the outer peripheral surface of the package in its width direction. Because the yarn end from the package has been moved toward the center of the outer peripheral surface of the package by the action of air currents of compressed air through the jet nozzles of the yarn directing mechanism, the yarn end can be reliably sucked and caught by the suction member, which reliably sucks the air in the central area of the outer peripheral surface of the package in the width direction. Thus, a size of the suction vent of the suction member can be reduced and a suction volume of the air can be reduced. Consequently, the energy required by the suction member for sucking and catching the yarn end can be reduced.
Although the invention has been described with respect to specific embodiments for a complete and clear disclosure, the appended claims are not to be thus limited but are to be construed as embodying all modifications and alternative constructions that may occur to one skilled in the art that fairly fall within the basic teaching of the claims.

Claims

A yarn winding device (11) that forms a package(P), comprising:
a winding roller(23) adapted to rotate in contact with the package(P) and to assist in winding of the package(P);

a cradle(22) that is adapted to rotatably support the package(P) and that is swingable in a contacting direction in which the package(P) comes into contact with the winding roller(23), and a separating direction in which the package(P) is separated from the winding roller(23);

a driving mechanism(24) that is adapted to drive the cradle(22) in the contacting direction and the separating direction;

a braking mechanism(26) that is adapted to brake rotation of the package(P); and

a yarn directing mechanism(71) that, when a yarn is cut, is adapted to cause a yarn end to move from the package toward a center of an outer peripheral surface of the package by an action of air currents,

wherein the yarn directing mechanism(71) includes jet nozzles(72) that are adapted to eject compressed air and that are arranged at positions that are on a downstream side of a contact portion between the outer peripheral surface of the package(P) and an outer peripheral surface of the winding roller(23) in a winding and rotating direction of the winding roller and at both ends of the outer peripheral surface of the winding roller(23), and

the jet nozzles(72) are arranged so that jet vents thereof are oriented toward center of the contact portion between the outer peripheral surface of the package(P) and the outer peripheral surface of the winding roller(23) in a longitudinal direction.
The yarn winding device(11) according to Claim 1, further comprising a controller(81) that, when the yarn is cut, is adapted to cause the driving mechanism(24) to separate the package(P) and the winding roller(23), the braking mechanism(26) to brake the rotation of the package(P), and the yarn directing mechanism(71) to eject the compressed air from the jet nozzles(72).
The yarn winding device(11) according to Claim 2, wherein the jet nozzles(72) of the yarn directing mechanism(71) are oriented toward the outer peripheral surface of the winding roller(23).
The yarn winding device(11) according to Claim 3, further comprising a driving source(27) that is adapted to produce a driving force,
wherein the winding roller(23) is a traverse drum with a traverse groove(28) formed on a surface thereof and is driven by the driving source(27), and
the package(P) is adapted to rotate upon receiving a force from the traverse drum.
The yarn winding device(11) according to Claim 3, further comprising:
a package driving source that is adapted to produce a driving force; and

a traversing device that is adapted to traverse the yarn,

wherein the winding roller(23) is adapted to be driven to rotate by a force received from the package(P).
The yarn winding device(11) according to any one of Claims 1 to 5, further comprising:
a yarn joining device(42) that is adapted to join ends of the yarn that has been cut; and

a suction member(61) that is adapted to suck and catch a yarn end from the package(P) when the yarn joining device(42) joins the yarn,

wherein a width of a suction vent(63) formed in the suction member(61) in a longitudinal direction is smaller than a width of the outer peripheral surface of the package(P) in a rotation axis direction, and

the suction vent(63) is adapted to suck air in a central area of the outer peripheral surface of the package(P) in the rotation axis direction.