IE46687B1

IE46687B1 - Improvements relating to the spooling of threads of thermoplastic material,in particular glass threads

Info

Publication number: IE46687B1
Application number: IE575/78A
Authority: IE
Original assignee: Saint Gobain
Priority date: 1977-03-23
Filing date: 1978-03-22
Publication date: 1983-08-24
Also published as: DK144006C; PL112729B3; IE780575L; PL205464A1; HU178096B; JPS53119328A; DK131478A; CS215107B2; AT382352B; MX147618A; YU68178A; ES468103A1; DE2812356A1; FI62806C; ATA209478A; AU3443778A; BR7801792A; NO781037L; BE865197R; LU79291A1

Abstract

In this device, the yarn (3), applied to the front face of a wind-on (delivery) drum provided at the end of the spindle, is seized by gripping means (70) arranged on the perimeter of the drum in order to lead the yarn into a circular groove made on the drum so as to wind the yarn thereon until the spindle is brought to the normal winding speed. The gripping means (70), preferably produced in the form of channels or notches, are at least three in number and are disposed on the front face of the wind-on (delivery) drum so that the angular distance which separates two successive members, which is measured from the axis of rotation of the drum, has a constant value.

Description

COMPLETE SPECIFICATION (54) IMPROVEMENTS RELATING TO THE SPOOLING OF THREADS OF THERMOPLASTIC MATERIAL, IN PARTICULAR GLASS THREADS (61) Patent of Addition to 43444 PATENT APPLICATION BY (71) SAINT-GOBAIN INDUSTRIES, A FRENCH BODY CORPORATE OF 62 BOULEVARD VICTOR HUGO, NEUILLY-SUR-SEINE, FRANCE.

Price 90p 6 6 8 7 The invention relates to improvements relating to winding threads of thermoplastic material such as glass threads. In particular the invention is an improvement in or modification of the invention described in our Irish Patent No. 43444 (hereinafter called the Main Patent) According to the invention described in the main Patent there is provided apparatus for winding a thread of thermoplastic material wherein a rotatable spindle has at a free end thereof a waste yarn wind-up device with a circular end face which communicates by way of thread.gripping means with an annular groove of the wind-up device, the construction and arrangement of end face, gripping means and annular groove being t t such that thread applied to the end face is taken up by the gripping means and guided .into the groove for winding therel η . Preferably such gripping means comprises two opposed slots on a single diameter or some other even number of diametrically opposed slots. Although the Applicant has found that such an arrangement was generally satisfactory it had certain disadvantages as will be explained with reference to Figs 1 to 4 of the accompanying drawings which represent schematically in end ί view the waste yarn wind-up described in the Main Patent. These figures I to 4 are identical to Figure 35 of the Main Patent. ' The figures show at 7 the wind-up device provided with two grooves 10 situated diametrically opposite each other and at 3; the strand or thread which ie to be gripped in the grooves 10 on rotation of the spindle -2ί υ 6 a 7 at the end of which tfie device 7 is mounted.

Figure 1 shows clearly how in order that the thread 3 may be held in the two grooves 10, it must be situated in a plane containing a diameter of the device 7. This requirement may fail to be fulfilled at the required moment, in particular for the following reasons; a) Misal ignment of the devices provided for holding the thread: or strand in position (for example, the holding finger 11 for holding the thread and the channel 13 described in the Main Patent with reference to Figures 1 to 3). The thread is then no longer in a diametrical IO plane D. This functional fault is illustrated in Figures 1 to 3. j Figure shows how the thread 3 is not situated in the diametrical plane D and is therefore held only in the upper groove. As the device 7 continues to rotate (figure 2), the thread 3, pulled downwards by the thread attenuating device (not shown here but described in the Main Patent with reference to Figures 1 to 3), tends to move out of this groove and finally escapes fiom it altogether (Figure 3). b) Sticking of the thread 3 (Figure 4) to the surface of the device 7 by deposits of solidified size on the surface of the device in spite of wetting of the system by spraying as described in the Main Patent with reference to Figure 17. As in the case of the defective functioning described under a) above, the thread is now no longer situated in the diametrical plane D and is held in only one groove (the lower.groove) -346687 from which it escapes as described above with reference to Figures 1 to 3 before encountering the second groove.

The Applicant has also found that the gripping devices must be regularly spaced apart on the front surface of the device so that rotation will not produce any imbalance which could impair rotation of the spindle.

According to the present invention there is provided apparatus for winding a thread of thermoplastic material in which a rotatable spindle has at a free end thereof a waste yarn wind-up device with a circular end face which communicates with an annular groove of the wind-up device IO by way of three thread gripping means which are arranged at angle^ of 120° to one another about the axis of rotation of the wind-up device, the construction and arrangement of end face, gripping means and annular groove being such that thread applied to the end face is taken up by two of the gripping means and guided into the groove for winding thereon.

Ig Preferably the gripping means are slots inclined at an angle of o or less to the front surface of the wind-up device to provide an acute angle connecting the slots with the annular groove.

In a preferred embodiment a thread ejection device is provided including a bar provided at one end with a V-shaped guide device to hold the thread in the annular groove of the wind-up device so that the thread will be wound in this groove, the said V-shaped guide device being attached I, -44 6 6 8 7 to said end of said bar by the end of one of the two arms of the V.

Apparatus in accordance with the invention will now be described by way of example with reference to the accompanying drawings in which:Figures 5 to 7 are schematic end views of a waste yarn wind-up device according to the present invention, represented in three successive operating positions: Figures 8 to 10 are views similar to Figures 5 to 7 representing three other successive operating positions of the same waste yarn wind-up device Ιθ Figure 11 is an elevational view in detail, representing one example of a gripping slot according to this Addition; Figure 12 is a partial view corresponding to Figures 22 and 23 of the Main Patent, provided to explain certain operating faults of the thread ejection device shown in the Main Patent; and I5 Figure 13 is a view corresponding to Figure 12, showing an improved thread ejection device according to the present invention.

Referring to Figures 5 to 10, the waste yarn wind-up device is provided on its front surface with three gripping slots 70 arranged at 120° from each other measured about the axis of the device 7. By virtue of this arrangement, it is no longer necessary to hold the thread or strand 3 strictly along a diameter of the front surface of the device 7. As can be seen from -5the figures, the thread 3 situated about the centre of the device 7 inevitably falls into two successive slots. There is no risk of missing the o slots for the thread since the distribution of the slots at angles of 120 from each other requires no preferential position of the device 7 for gripping the thread in these slots. Moreover, this arrangement balances the device 7.

Figures 5 to 10 illustrate how the thread will be gripped no matter what the initial position of the device 7 and even though the thread is not situated on the centre of the device. An inspection of these figures, which are self-explanatory, will show that the thread or strand 3 wilt; in all cases fall into two consecutive slots 70. ! Referring now to Figure 11, this is an elevational view showing the spindle 4 on which the thread or strand is wound as described in the Main Patent. The device 7 fixed to the spindle is formed with a groove 8 as described in the Main Patent, slots 70 arranged as described above and which guide the thread or strand into the groove 8, and a smooth, shiny front surface with which the thread comes into contact.

The Applicant has observed that when a slippery size is used, the thread slides along the cord before it is ruptured at the level of attenuating rollers 19 and 20, as described in the Main Patent. To overcome this disadvantage, the present invention provides that the slots 70 are inclined at an angle of 45° or less to the front surface 9, to provide an -646037 acute angle connecting this groove to the front surface. By virtue of this feature, the thread or strand is always gripped in the base of the groove and will not slip out of position.

The description will now be continued with reference to Figures 12 and 13.

Using the same reference numerals as in the Main Patent, Figure represents the thread ejection device which was described in the Main Patent with reference to Figures 22 and 23. This ejection device comprises a bar 15 at the end of which is mounted a V-shaped device 51 which serves |0 to hold the thread in the groove 8 of the starting device 7. The V-shaped / device 51 also has other features mentioned in the Main Patent. With this type of V-shaped device, it has been found that when the operator throws the thread or strand 3 into the thread attenuating device (not shown in Figure 12) for normal transfer to an automatic winding machine, the thread is liable to get caught in the space A between the bar 15 and one of the arms of the V 51 and cannot be released.

To obviate this disadvantage, the present invention provides that this V-shaped device, indicated by the reference numeral 71, is attached to the end of the bar 15 by the end of one of thp two arms of the V-shaped device 71. There is therefore no risk of the thread or strand getting caught between the bar 15 and one of the arms of the V. During normal transfer, -7the thread is conducted to B by the fork 47 so that it will be directed to the smooth part 52 which is contiguous with the channel 8 and on which the transfer ring will be formed, as described in the Main Patent.

Tests carried out by the Applicant have shown that where the thread attenuating rollers 19,20 are made of metal, the hard rollers rarely enable the thread to be cut progressively. It has therefore been attempted to find a softer material which will ensure the success of this operation at all times. The Applicant has found that the best results were obtained with an elastomer, in particular a polyurethane resin, having a Shore hardness |0 of 95. The rollers are preferably produced by casting on a metal core.

Claims

CLAIMS:

1. Apparatus for winding a thread of thermoplastic material in which a rotatable spindle has at a free end thereof a waste yarn wind-up device with a circular end face which communicates with an annular groove of the 5 wind-up device by way of three thread gripping means which are arranged at angles of 120° to one another about the axis of rotation of the wind-up device, the construction and arrangement of end face, gripping means and annular groove being such that thread applied to the end face istaken up by two of the gripping means and guided into the groove for winding therein. 10

2. Apparatus according to Claim 1 in which the gripping means are o slots inclined at an angle of 45 or less to the front surface of the wind-up device to provide an acute angle connecting the slots withthe annular groove

3. Apparatus according to Claims 1 or 2, comprising a thread ejection device including a bar provided at one end with a V-shaped guide device I5 to hold the thread in the annular groove of the wind-up device so that the thread will be wound in this groove, the said V-shaped guide device being attached to said end of said bar by the end of one of the two arms of the V.

4. Apparatus according to any one of claims 1 to 3, in which thread attenuating rollers are provided under the wind-up device for pulling >q and attenuating the thread before it engages in the gripping means, said rollers being made of an elastomer. -94306?

5. Apparatus according to Claim 4, in which the elastomer has a Shore hardness of 95.

6. Apparatus according to Claim 5, in which the elastomer is a polyurethane resin. 5

7. Apparatus according to claims 4, 5 or 6 in which the said rollers are produced by casting the elastomer on a metal core.

8. Apparatus for winding a thread of thermoplastic material constructed and arranged substantially as described herein with reference to figures 5 fc 11 and figure 13 of the accompanying drawings.