GB2037335A

GB2037335A - Yarn Storage and Feeding Device

Info

Publication number: GB2037335A
Application number: GB7942710A
Authority: GB
Original assignee: Savio SpA
Current assignee: Savio SpA
Priority date: 1978-12-27
Filing date: 1979-12-11
Publication date: 1980-07-09
Also published as: SE7910289L; IT7831315A0; FR2445288A1; JPS5593772A; IT1101097B; DD148331A5; DE2951346A1

Abstract

A yarn storage and feeding device for textile machinery, particularly suitable for flamed or pile yarns. The device comprises an upstanding finger alongside a yarn storage drum or cylinder, adjacent to that end thereof on which the turn is wound onto the drum or cylinder. The finger is rotatably movable relative to the cylinder or drum and has one or more grooves formed on its outer surface, for lifting yarn turns and then depositing them again on the cylinder or drum spaced apart from one another and with their piles combed by the grooves. <IMAGE>

Description

SPECIFICATION Yarn Storage and Feeding Device This invention is concerned with yarn storage and feeding devices for supplying yarn on demand to textile machinery, and more particularly to such a device for storing and feeding fancy yarns, such as flamed or pile yarns.

Many devices are known comprising a drum or cylinder on which yarn turns are wound up in mutual side-by-side contacting relationship to provide a reservoir of yarn, with the yarn being withdrawn, generally intermittently, by the textile machinery such as a loom. In the art, two basic variants of such apparatus are known, that is an embodiment in which the drum is stationary relative to a fixed bearing or support while a thread distributing arm rotates thereabout, this arm winding up thread turns at one of its ends; and an embodiment in which the drum rotates about its own axis withdrawing the thread from a fixed location to wind it up on the drum. Devices of both these types are well known, and some of them are described, for example, in U.S. Patent Specifications Nos. 3,093,339, 3,776,480, 3,834,635, 3,944,156,3,791,598, 2,625,340, 3,419,225 and 3,702,176.

In all of these devices the last thread turn being wound up on the drum is deposited in close contact with the turn deposited on thedrum in the preceding turn or revolution.

It has been found that, where a fancy yarn is used, the last turn being deposited on the drum alongside the preceding turn may interfere with that preceding turn, with laterally extending filaments of the preceding turn of yarn being lapped by the last turn of yarn on the drum.

Because the yarn is withdrawn from the opposite end of the drum to that on which it is deposited, each turn or convolution to be unwound from the drum may have lateral filaments projecting therefrom that are trapped or tightened under the thread turn or convolution next thereto. As a result, the thread withdrawal from the cylinder or drum is extremely difficult because in order to unwind the yarn turn by turn from the drum, those trapped filaments have to be pulled free. This trapping of filaments of the yarn is referred to herein as partial lapping of the yarn.

It is an object of the present invention to overcome or reduce the above disadvantages, and accordingly to allow an easy and simple unthreading or unwinding of the yarn from the drum of a yarn storage and feeding device, even when fancy threads are used.

The relative rotation between the yarn guide eye and the drum may be achieved by moving the yarn guide eye and the upstanding finger in a circular path aroung the drum which is stationary, or by rotating the drum while the yarn guide eye and the upstanding finger remain stationary.

Drawings Figure 1 is a schematic side view of a device according to the invention; Figure 2 is an enlarged view of a detail of the device shown in Figure 1; and Figure 3 is a section through the upstanding finger of Figure 2, in relation to the drum or cylinder of Figure 1.

The embodiment of the invention shown in Figure 1 comprises a cylinder or drum 1, at the base of which a hollow rotary arm 2, rotably driven by a pulley 3 connected to a motor through a belt, not shown in the drawing, is provided for distributing in the form of turns or convolutions 4 a yarn 5 from, for example, a yarn bobbin passing through a hollow hub 6 integral with said pulley 3 and arm 2.

Pulley 3, hollow hub 6 and drive arm 2 are rotably mounted on a stationary bracket 7.

Cylinder or drum 1 (which is slightly conical, slightly decreasing in diameter in the direction of the free end of the cylinder or drum) is mounted on bearings carried by hub 6, and its rotation is restrained by gears, such as described in U.S.

Patent Specifications Nos. 3,093,339 and 3,776,480, or by permanent magnets, such as described in U.S. Patent Specification No.

3,834,635, or by rolling bearings, such as described in U.S. Patent Specifications Nos.

3,944,156,3,791,598 and 4,090,677.

Yarn convolutions 4, distributed at the base of cylinder or drum 1 by rotary arm 2, are moved upwardly as viewed in the drawing by oscillating members (not shown) mounted on hub 6, or by the thrust of the last turn or convolution being wound and which operates between the previously wound turn or convolution and a rigid abutment surface. The structure of the feeder hitherto described is of no significance for the purposes of the present invention and has been given only to represent an embodiment of a -known type of thread storing device.

In the device illustrated, since the turns or convolutions 4 are placed closely side by side to one another, where the yarn 5 has laterally extending filaments, the turn or convolution being wound up as the last turn or convolution on the cylinder or drum will, by being placed side by side to that deposited in the preceding turn or revolution, lap over the pile or laterally extending filaments projecting from the yarn's previous turn, which normally would obstruct the unwinding operation from the other end of the cylinder or drum.

The device of the present invention overcomes such a disadvantage in a simple and economical manner. To this end, alongside the cylinder or drum 1 there is provided an upstanding finger 8 which is rotatable relative to the cylinder or drum 1 together with the yarn guide eye of the drive arm 2. In other words, if said cylinder or drum 1 is stationary and the drive arm 2 rotates thereabout, then the finger 8 is integral with the arm 2 and rotates therewith. Should the arm 2 be stationary while the drum or cylinder rotates, also the finger 8 is stationary.

The finger 8 comprises on its surface facing outwardly of the cylinder or drum two shaped grooves 9 and 10 which are spaced apart from each other (but also more than two grooves could be provided, or even only one groove or equivalent expedient), as particularly shown in Figures 2 and 3. Preferably, the groove 9 in the finger 8 is axially positioned just downstream of the yarn guide eye of the drive arm 2, from which the yarn exits and is deposited on the cylinder or drum 1.

Groove 9 receives, and lifts slightly from the cylinder or drum 1, the yarn turn or convolution adjacent to that which has been last deposited on the cylinder or drum (Figure 3), while another yarn turn or convolution that has previously been deposited is lifted by groove 10. Thus, during the relative rotation between said finger 8 and cylinder or drum 1, the finger lifts one or two yarn turns or convolutions away from the cylinder or drum, freeing any trapped filaments or piles of the yarn forming such a convolution or such convolutions away from below the convolutions next deposited on the cylinder or drum, while carrying out a combing action of the yarn.

Thus, by dragging in the grooves of the finger 8, the yarn is combed or teased, so that any filaments or piles projecting therefrom tend to lie down parallel with the thread, less and less projecting therefrom and reducing the possibility of being blocked below a next turn or convolution.

Still preferably, said grooves 9 and 10 are spaced apart from each other by a larger spacing than the diameter of the yarn 5, so that the turns or convolutions lifted by the finger 8 away from the cylinder or drum surface are deposited again on the cylinder or drum spaced apart by the turn or convolution next thereto: if the yarn turns or convolutions are fed to the free end of the cylinder or drum by mechanical members directly operating on the individual turns or convolutions, the latter would thus remain spaced apart from one another until withdrawal from a using machine.

If desired, additional combing or teasing elements can be advantageously associated with the finger 8, which elements are effective on the thread or promote the orientation and adhesion thereto of any filaments or piles projecting from the thread.

Claims

1. A yarn storage and feeding device comprising means for winding turns of yarn on a drum from a yarn supply zone axially spaced from one end of the drum, for subsequent withdrawal on demand axially from the other end of the drum, said means comprising a yarn guide eye radially outwardly of the drum adjacent the first end thereof and means for effecting relative rotation between the yarn guide eye and the drum, and an upstanding finger alongside the drum, rotatable relative to the drum together with the yarn guide eye, with a lateral groove on the finger for receiving one of the turns of yarn to lift the yarn from the drum.

2. A device according to claim 1, wherein the groove is at an axial position slightly downstream of the yarn guide eye.

3. A device according to claim 1 or claim 2, wherein the finger is provided with one or more other lateral grooves for receiving one or more other turns of yarn to lift the yarn from the drum.

4. A device according to any preceding claim, wherein the or each groove of the finger is shaped to effect a combing action on yarn passing therethrough.

5. A device according to any preceding claim, wherein the or each groove of the finger has associated therewith additional combing or teasing elements for the yarn.

6. A yarn storage and feeding device substantially as described herein with reference to the drawings.