GB2092624A - Apparatus for taking up slack yarn in a winder - Google Patents

Abstract

In a yarn slack take-up apparatus for retaining a fed yarn therein during a knotting operation in a winder, a yarn sucking action is caused in the tube (2) only when the knotting operation is carried out, while the sucking action of the tube (2) is stopped by movement of tube opening 4 from shutter plate opening 7 to lie behind and be blocked by the shutter plate. <IMAGE>

Description

SPECIFICATION Apparatus for taking up slack yarn in a winder The present invention relates to an improved apparatus for taking up slack yarn in a winder or the like. More particularly, it relates to an improved slack tube which is provided on a winder for sucking a yarn during the knotting operation.

When a yarn spun in a pneumatic spinning apparatus or the like is wound on a package or the like, or when a bobbin is changed and re-winding is carried out, if a yarn being wound is broken, a splicing or knotting operation must be carried out.

A slack tube is provided to suck the yarn ends and eliminate slack during the splicing operation.

However, since this slack tube continues the sucking action even when the splicing operation is not carried out, an unnecessary load is imposed on the suction system.

An object of the present invention is to provide a yarn slack take-up device by means of which the load imposed on the suction system is reduced to a minimum.

According to the present invention, the sucking action is caused in the slack tube only when the knotting or splicing operation is carried out, while the sucking action of the slack tube is stopped when the knotting or splicing operation is not being carried out.

In accordance with the invention there is provided apparatus for taking up slack yarn in a winder or the like which includes two yarn holding and guiding members arranged, on yarn breakage, to hold the yarn ends on the package side and feeding side and guide them to a knotter, the apparatus comprising a shutter plate having an opening formed along the path of the yarn being wound on the package, a slack tube arranged behind the shutter plate, being swingably supported on a main suction tube and having an end suction opening in close contact with the rear surface of the shutter plate, a first oscillating member for swinging and moving the slack tube so that the suction opening in the shutter plate, and a second oscillating member arranged so that said first oscillating member is operated when the yarn holding and guiding members guide the yarn ends to the knotter.

One embodiment of apparatus in accordance with the present invention will now be described in detail with reference to the accompanying drawings, in which: Fig. 1 is a perspective view illustrating this embodiment of apparatus in accordance with the present invention; Fig. 2 is a side view of the apparatus shown in Fig. 1; Fig. 3 is a plan view of the apparatus shown in Figs. 1 and 2; and, Fig. 4 is a diagrammatic side view illustrating an embodiment of spinning apparatus which incorporates the apparatus for taking up slack yarn.

One common main suction tube 1 is laid out on the back portions of units arranged in parallel across the entire width of the machine, and the main suction tube 1 is connected to a suction system (not shown). Slack tubes 2 for the respective units are mounted on the main suction tube 1 for horizontal swinging movement. More specifically, each slack tube 2 is loosely fitted in a supporting piece 3 projecting from the main suction tube 1 , or else the supporting piece 3 may be constructed as an elastic member or a bellows member. A suction opening 4 is formed at the outer end of each slack tube 2, and the suction opening 4 is brought into close contact with a shutter plate 5. In order to bring the suction opening 4 into close contact with the shutter plate 5, the slack tube 2 is always urged to the left in Figs. 1 to 3 by a spring (not shown).Openings 7 are formed in the shutter plate 5 in alignment with the respective paths of individual yarns 6 being wound on packages 26 (Fig. 4) in the respective units, so that the distance between every two adjacent openings 7 is the same as the distance between every two adjacent units. A slub catcher 8 is disposed below each opening 7. A first oscillating member 21 is provided for swinging and moving the slack tube 2 so that the suction opening 4 of the slack tube 2 is in communication with the opening 7 of the shutter plate 5, and a second oscillating member 1 6 is provided for swinging and moving the slack tube 2 in the reverse direction, away from the opening 7. The structures of the first and second oscillating members 21 and 16 will now be described.

An L-shaped arm 9 is pivoted on the slack tube 2, and the arm 9 is urged by a spring 10 so that it rotates in the clockwise direction about a horizontal axis as shown in Figs. 1 and 2. A stop 11 is disposed on the slack tube 2 to limit rotation of the L-shaped arm 9. A cam piece 12 is mounted on a frame 13 so that an inclined face 14 of the cam piece 12 can come into abutting contact with the vertical limb 1 5 of the L-shaped arm 9. A bar 1 6 capable of reciprocating in the longitudinal direction of the machine is disposed above the slack tube 2. A striker 17 is mounted on the bar 16. The striker 17 makes abutting contact with the L-shaped arm 9 when the L-shaped arm 9 is brought into abutting contact with the stop 11.

The bar 1 6 makes a traverse movement and its width is the same as the width of a feed roller (not shown). The bar 1 6 always traverses the yarn so as to prevent wearing of the feed roller; this is caused when the yarn is always kept in contact with a specific portion of the feed roller.

A knotter truck 20 is arranged to move along a plurality of units arranged parallel to one another for performing the knotting or splicing operation.

The knotter truck 20 comprises a knotter 23 and a pair of yarn-holding members for holding the ends of a broken yarn end guiding the yarn ends to the knotter 23. Reference numeral 21 represents a swinging arm and when it swings, the top end thereof makes abutting contact with the depending portion 1 5 of the L-shaped arm 9.

Reference numeral 22 represents a guide roller.

The operation of the apparatus of the present invention will now be described.

When the slub catcher 8 does not detect a slub or yarn breakage does not occur, the bar 1 6 makes a reciprocating movement while traversing the yarn. The L-shaped arm 9 is pulled by the spring 10 and kept in abutting contact with the stop 1 Accordingly, the striker 1 7 is kept in contact with the L-shaped arm 9 and brings the L-shaped arm 9 downwards in Fig. 3 with the traverse movement, and the slack tube 2 having the L-shaped arm 9 pivoted thereon is kept in the state where it is rotated in the counterclockwise direction with the supporting piece 3 acting as the fulcrum. The suction opening 4 at the outer end of the slack tube 2 is therefore kept in contact with the non-open portion of the shutter plate 5.

Therefore, in this state, suction of air through the suction opening 4 is prevented.

When yarn breakage takes place in the abovementioned state, the knotter truck 20 stops at a position confronting the unit where yarn breakage has taken place, in response to a signal from the slub catcher 8, and the yarn-holding members (not shown) of the knotter truck 20 hold the packageside and feed-side yarn ends of the broken yarn 6 and guide them to the knotter 23. When the knotter bill of the knotter 23 holds the feed-side yarn end, the slack tube 2 is oscillated so that the suction opening 4 of the slack tube 2 is in communication with the opening 7 in the shutter plate 5. More specifically, in response to the signal from the slub catcher 8, the swinging arm 21 rotates in the clockwise direction in Fig. 2 and makes abutting contact with the depending portion 1 5 of the L-shaped arm 9 to rotate the Lshaped arm 9 as indicated by a one-dot chain line.

Since the depending portion 1 5 of the L-shaped arm 9 is brought into contact with the inclined face 14 of the cam 12 at this time, upon rotation of the arm portion 1 5 in the counterclockwise direction in Fig. 2, the depending portion 15 moves upwards in Fig. 3, with the result that the slack tube 2 which is integrated with the L-shaped arm 9 is oscillated in the direction A in Fig. 3 about the supporting piece 3 as the centre, and the suction opening 4 communicates with the opening 7, whereupon the slack tube 2 sucks the yarn end through the opening 7.

After the knotting or splicing operation by the knotter 23 has been completed, by rotation of the swinging arm 21 in the counterclockwise direction, the depending portion 1 5 of the Lshaped arm 9 is set free and the L-shaped arm 9 is returned to the original position as indicated by a solid line in Fig. 2 by the elastic force of the spring 10. Accordingly, when the bar 1 6 making the traverse movement moves downward in Fig. 3, the striker 1 7 makes abutting contact with the L-shaped arm 9 to press the L-shaped arm 9 downwards (in Fig. 3). Therefore, the slack tube 2 is also oscillated to the position indicated in Fig. 3 and the suction opening 4 separates from the opening 7, with the result that the sucking action of the slack tube 2 is stopped.

According to the present invention, as the opening of the slack tube 2 communicates with the opening in the shutter plate to suck the yarn on the spinning side into the slack tube simultaneously with a knotter bill of the knotter (not shown) holding the yarn ends on the package side 26 and spinning side 27 and knotting them together, the yarn continuously spun during the knotting operation is sucked and retained in the slack tube 2, preventing an occurrence of kinky threads due to loosening of yarns.

During the operation for guiding the yarns on the package side and feeding side into the knotter 23, the sucking action by the slack tube 2 is not applied to the yarn because the slack tube is closed by the shutter plate 5. So, even if the yarn on the spinning side passes in front of the opening 7 in the shutter plate 5 during the yarn guiding process, the yarn is not sucked into the slack tube, and then a miss in the process for guiding the yarn into the knotter can be prevented.

In the embodiment shown in Fig. 4, the device for holding the yarn end on the feeding side is a suction pipe 28. The pipe 28, which is able to rotate to the position shown in solid line about a supporting shaft 29 secured on the knotter, turns in the counterclockwise direction, sucking the yarn on the feeding side 27 therein, and inserts the yarn Ya into the knotter in conjunction with another guide at the position shown by the chaindotted line 28a. At this time, if the sucking action of the slack tube 2 is affected, the yarn can be held in only if the suction force from the suction pipe 28a is greater than the suction force from the slack tube 2. In the present invention, as aforementioned, it is not necessary to make the suction force of the suction pipe 28 larger because the sucking action is not effected at the opening 7 during the yarn guiding operation into the knotter.

As will be apparent from the foregoing description, in the apparatus of the present invention, since the sucking action of the slack tube is exerted only during the splicing action and the sucking action is stopped while the yarn is travelling during the winding operation, the load imposed on a blower of the suction system can be reduced to a minimum. Therefore, the size of the blower can be minimised and the consumption of electric power can be reduced.

Claims (4)

1. Apparatus for taking up slack yarn in a winder or the like which includes two yarn holding and guiding members arranged, on yarn breakable, to hold the yarn ends on the package side and feeding side and guide them to a knotter, the apparatus comprising a shutter plate having an opening formed along the path of the yarn being wound on the package, a slack tube arranged behind the shutter plate, being swingably supported on a main suction tube and having an end suction opening in close contact with the rear surface of the shutter plate, a first oscillating member for swinging and moving the slack tube so that the suction opening of the slack tube communicates with the opening in the shutter plate, and a second oscillating member arranged so that said first oscillating member is operated when the yarn holding and guiding members guide the yarn ends to the knotter.

2. Apparatus as claimed in claim 1 , wherein said first oscillating member comprises an Lshaped arm pivoted on the slack tube and urged by spring means to rotate in a first direction, a stop disposed on the slack tube to limit rotation of the L-shaped arm in said first direction, and a cam piece mounted on a frame so that an inclined face of the cam piece makes abutting contact with the L-shaped arm.

3. Apparatus as claimed in claim 1 or 2, wherein said second oscillating member is a swinging arm one end of which makes abutting contact with the first oscillating member to rotate it and to connect the suction opening of the slack tube with the opening in the shutter plate when yarn breakage takes place and the yarn holding and guiding members hold the respective yarn ends.

4. Apparatus substantially as hereinbefore described with reference to the accompanying drawings.