GB2144455A

GB2144455A - Doffer robot for open-end spinning machine

Info

Publication number: GB2144455A
Application number: GB08415003A
Authority: GB
Inventors: Alan Smith; Bhupendra Patel; Stephen William Yates
Original assignee: Hollingsworth GmbH
Current assignee: Hollingsworth GmbH
Priority date: 1984-06-13
Filing date: 1984-06-13
Publication date: 1985-03-06
Also published as: GB8415003D0

Abstract

A doffer robot (1) includes a transport conveyor for empty conical winding tubes. The tubes (4) roll along the chute of the conveyor and on leaving the chute pass a reversing portion (4a) where every alternate tube (4) is reversed to arrive at a pre-winding position (4b) where seeding yarn (5) extending between a supply package (6) and the last preceding pre-wound tube (4c) is drawn into position ready for formation of the transfer tail. The pre-wound tube is then substituted for the full package doffed by the robot. <IMAGE>

Description

SPECIFICATION Doffer robot for open-end spinning machine The present invention relates to a doffer robot for an open-end spinning machine incorporating both a doffer robot and a piecer-cleaner robot.

It has been known to provide for automated doffing and piecing in open-end spinning machines by use of a doffer robot which patrols the two sides of the machine and, upon receipt of a "package full" signal, will stop at a particular spinning station, remove the full package, and replace that with a tube which may be either cylindrical or conical, to serve as the core on which the next package is to be wound. A separate piecer-cleaner robot will then arrive at the same spinning station once it has been vacated by the doffer robot and will clean the open-end spinning chamber and then insert a "seeding" end of yarn of yarn into the spinning chamber and, when spinning resumes, the seeding end becomes a part of the package being delivered.The piecer-cleaner robot also services a spinning station at which a yarn break may have occurred in which case there will be no need for the doffer to attend to that station first, because the package will not yet have become fully wound.

This known doffer robot is supplied with empty tubes and part of the doffing operation involves transferring a short length of the spun yarn from the full package to the tube by doffing "onthe-fly" and winding a tail on the tube before that short length of yarn is cut from the package and has its opposite end introduced into the spinning chamber to serve as the seeding yarn for the resumption of the spinning operation.

According to the present invention we provide a doffer robot including means for receiving a plurality of empty yarn package support tubes; means for engaging a full package at a spinning station and displacing that full package into a position to be transferred to a conveyor of the open-end spinning machine with which the doffer robot is used; means for placing a said empty tube in place of the doffed full package at the spinning station; means carried by the doffer robot for supporting a package of seeding yarn; and further means carried by the doffer robot for prewinding said tubes with seeding yarn to povide a transfer tail and a start to the traversed build-up after departure of the doffer robot from said spinning station.

The pre-winding of the tubes while they are being carried by the patrolling doffer constitutes a radical departure from prior art openend spinning machine operation.

In order that the present invention may more readily be understood the following description is given, merely by way of example, with reference to the accompanying drawings in which: The sole Figure is a general arrangement view of a doffer robot for use with an openend spinning machine.

The doffer robot shown in the drawing may be used with a double-sided open-end spinning machine of the type shown in our copending British Patent Application No.

(Folio N37753). Such a machine has two banks of spinning stations, one along one side of the elongate machine frame and the other along a second side of that frame.

The doffer robot 1 shown in the drawing patrols continuously around the open-end spinning machine in a repeating circulating motion until it arrives at a spinning station whose product yarn package is full. The doffer robot then stops, doffs that full package and replaces it by a preferably conical, winding tube on which a short length of seeding yarn has become pre-wound while the doffer has been patrolling. It leaves the spinning station ready for the piecer-cleaner to piece-up such an inserted pre-wound tube. The doffer robot is able to pre-wind its tubes as and when they are needed. There is thus no need for the doffer robot to return to the head end to receive further empty tubes from the conveyor until all six of its tubes have been pre-wound and then inserted.

The drawing illustrates the general arrangement of the doffer robot.

The projecting end 2 of the doffer robot is defined by a tube transport conveyor which receives empty winding cores, which may be either cylindrical or conical, and transports them along a shallowly downwardly inclined path towards a pre-winding station 3.

When the tubes 4 arrive at the lower end 8 of the conveyor they roll off and arrive at a position 4a where every second tube 4 is inverted. This compensates for the fact that conical tubes on the conveyor will have alternating orientation of the narrower and wider ends.

Just before the tube 4 drops from the inversion position 4a to its next position 4b, a previously pre-wound tube has been carried leftwardly away from the pre-winding location 4b and into a holding location 4c by means (not shown) linked for operation simultaneously with opening of a latch at the delivery end of the tube transport conveyor to release the next tube from the bottom of the conveyor.

The strand of seeding yarn 5 from a seeding yarn supply package 6 to the pre-wound tube 4c passes the end of the just delivered empty tube at position 4a, and becomes trapped against and then wound on that end of this tube. Before winding can start, the yarn 5 is severed from the tube at position 4c.

The pre-winding operation provides the tube 4 with a transfer tail and with the start of a traversed build up sufficient to allow piecing up of an open-end spinning station, for example by means of the automated piecing system of our co-pending British Patent Application No. 8411 793.

At this stage the doffer robot is able to carry out the doffing operation by removing the full package by means not shown, and replacing it with a pre-wound tube which is carried by a pivoting arm 7 from one portion 4dto the winder of the spinning station (at position 4c).The doffed full package is lowered onto a return conveyor (not shown) which passes the full packages along the length of the open-end spinning machine to a delivery point. Then the doffer robot departs and the piecer robot (not shown) comes to that spinning station, cleans out the spinning chamber of any fibrous debris and introduces the end of the length of seeding yarn from the pre-wound tube into the spinning chamber to recommence spinning.

Transfer of the pre-wound tube from position 4cto position 4d, by means (not shown), is able to be effected once the yarn 5 has been severed at the start of the pre-winding of the tube at position 4b.

The tube conveyor may be of the kind disclosed and claimed in our co-pending British Patent Application No. (Folio N37937).

Claims

1. A doffer robot including means for receiving a plurality of empty yarn package support tubes; means for engaging a full package at a spinning station and displacing that full package into a position to be transferred to a conveyor of the open-end spinning machine with which the doffer robot is used; means for placing a said empty tube in place of the doffed full package at the spinning station; means carried by the doffer robot for supporting a package of seeding yarn; and further means carried by the doffer robot for pre-winding said tubes with seeding yarn to provide a transfer tail and a start to the traversed build-up of yarn on the tube, ready for piecing up of said started build-up after departure of the doffer robot from said spinning station.

2. A doffer robot according to claim 1, wherein said means for receiving empty yarn package support tubes comprise a winding tube transport conveyor extending along the doffer robot for transporting empty yarn winding tubes, wherein means for supporting a package of seeding yarn is located near a first end and yarn is able to pass from the package towards the second end to a pre-winding station between said first and second ends, and wherein the doffing means is effective to doff a package underneath the doffer robot and the means for placing a pre-wound tube in place of the doffed package are effective to carry a pre-wound tube from said pre-winding station towards said first end of the doffer robot.

3. A doffer robot according to claim 1 or 2, wherein the winding tube transport conveyor is able to accept conical tubes arranged with alternating orientation and including means for inverting every second tube delivered by the winding tube transport conveyor.

4. A doffer robot substantially as hereinbefore described with reference to, and as illustrated in, Figures 2 to 5 of the accompanying drawings.