GB1583609A - Mechanical engagement between a spindle and a tubular member - Google Patents

Description

(54) MECHANI CAL ENGAGEMENT BETWEEN A SPINDLE AND A TUBULAR MEMBER (71) We, ANIC S.p.A., an Italian company, of Via Mariano Stabile 216, Palermo, Italy, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement This invention relates to mechanical engagement between a rotating spindle and a tubular member, e.g. a bobbin, to be rotated by the spindle. In particular, this invention relates to the clutching, centering and driving of bobbins on their respective spindles during the operation of winding, under tension at a high speed, textile yarns to form cops.

The invention is useful in the textile industry in those machines in which winding of threads and yarns onto bobbins is carried out automatically at a high speed and under high tension, such as for example drawing and doubling machines, ring spinning machines, recopping machines, and drawing and elasticising machines.

The threads and yarns are wound onto a bobbin, which is a metallic supporting member coated with a sheath of a thermoplastics material. The thread-supporting or yarn-supporting member itself is called a bobbin, wheras the finished article, i.e. the thread or yarn wound onto the bobbin, is commonly called a cop.

At present, to effect winding of threads or yarns onto bobbins, there are used machines which permit the simultaneous winding of the threads or yarns onto a large number of bobbins. Each bobbin is rotated at a high angular speed by its respective spindle. On completion of the winding operation, the cops are taken off and empty bobbins for new lengths of threads are positioned on the spindles.

The machines used for this purpose are generally equipped with bobbin-loading devices, which, without any manual intervention, slip the empty bobbins from above onto the spindles and remove the cops from the spindles. Engagement between bobbin and the spindle is achieved by engagement between a male trilobe with which the spindle is equipped and a female trilobe formed on the bottom face of the bobbin. As a result, engagment can be obtained only whenever the three faces of the trilobes, which faces are spaced apart by 120 from each other, coincide exactly. Accordingly, loading of the bobbins onto the spindles by an automatic mechanism may take place only after very accurate positioning of the bobbins on the loading device.Even this precaution is not sufficient to ensure correct positioning of the bobbins on the spindles since it is also necessary that all the spindles be in an exact angular phase relationship with each other and with the bobbins as well, so that the spindles receive the bobbins in any of the three angular positions which are exclusively allowed. Such a requirement is virtually impossible to fulfill since the drive from the mainshaft to the spindles is effected by means of a belt drive, and thus belt slip is possible, causing the angular phasing established beforehand to go astray.

It is not possible for the spindles to undergo small angular rotations with the bobbins in position to effect engagement between the spindles and bobbins, since breakage of the yarn, already arranged for subsequent winding, would take place.

The only method which is practicable at present is for an operator to effect engagement between the spindles and the bobbins.

It has been statistically shown that about 80% to 85% of the empty bobbins loaded onto the spindles have to be manually engaged by the operator.

According to the present invention, there is provided, in combination, (a) a tubular member having a female trilobe in an end face thereof and (b) a device for providing mechanical engagement between a rotating spindle and the tubular member so that the tubular member can be rotated by the spindle, the device comprising (i) a cam having three cam surfaces, which cam is fixed to, or adapted to be fixed to, the spindle so as to be rotatable therewith, and (ii) a floating cam follower associated with each of the three cam surfaces, the three cam followers being angularly spaced from one another by 1200, the device being such that, upon rotation of the cam relative to the cam followers, each cam surface engages its respective cam follower to cause the cam followers to move radially outwardly to engage the female trilobe of the tubular member.

By virtue of the present invention, the above described manual engagement can be dispensed with so that the time required for positioning of tubular members such as bobbins, which is about 3 minutes for each loading step, is reduced.

The diameter of the circle circumscribing the followers, when the followers are not engaged by the triangular cam, is preferably less than or equal to the diameter of the cicle inscribed in the female trilobe of the tubular member. The diameter of the circle circumscribing the followers, when the followers are engaged by the triangular cam, is preferably equal to the diameter of the circle which is circumscribed by the female trilobe in the bottom of the tubular member.

For a better understanding of the invention, reference will now be made, by way of example, to the accompanying drawings in which: Figure 1 is a perspective fragmentary view of the prior arrangement, showing a spindle provided with a male trilobe 1 m; Figure 2 is a fragmentary view of a bobbin for use with the device shown in Figure 1 having a female trilobe lf shown in phantom lines; Figure 3 is a diagrammatical plan view from beneath of the bobbin shown in Figure 2; Figure 4 is an exploded view of a device used according to this invention to replace the male trilobe shown in Figure 1; Figure 5 is a sectional view of the device of Figure 4 in its inoperative position;; Figure 6 is a sectional view, similar to that of Figure 5, which shows the device in its operative position after the spindle has rotated clockwise, wherein there is mechanical engagement between the spindle and the female trilobe of the bobbin; and Figure 7 is a cross-sectional view taken along line VIl-VIl of Figure 6.

Referring to Figures 4 to 7, there is shown a device used according to the present invention, consisting of a triangular cam 10 (best seen in Figure 4) which is sandwiched between two annular plates 12 and 13. These plates are connected by three screws 17 and spaced apart by three spacers 16. The screws 17 are angularly spaced at 120 from each other. Three floating followers 14, angularly spaced apart from each other by 120 , are arranged in a symmetrical array between the spacers 16, so that there is an angle of 60 between a spacer and a follower.

The followers 14 are called "floating followers" for the following reason. They fit onto respective resilient dowels 18 having an outside diameter which is smaller than the diameter of the bore of the follower so that the followers are able to "float" radially inward or radially outward, that is, towards or away from the inner surface of the trilobe of the bobbin 5.

Each floating follower 14 is bevelled at the top (best seen in Figure 4). The purpose of this will be made clear below.

As can be seen from Figure 4, the cam 10 has an inner bore which matches spindle 3, and the two ends of the cam 10 are terminated by cylindrical surface the outside diameters of which are equal to the inner diameter of the annular plates 12 and 13. The triangular cam 10, thus sandwiched between the annular plates 12 and 13, is slipped onto the spindle so as to rotate rigidly therewith.

It will be seen that the device according to Figures 4 can be used to replace the male trilobe Im of the conventional device shown in Figure 1. Figure 7 shows in detail how the spindle 3 and the bobbin 5 are mechanically engaged in use. In Figure 7, the male trilobe lm of the conventional device shown in Figure 1 on the bottom of the shaft 3, has been replaced by the device shown in Figure 4. The centering cone 2, conventional in itself, has been retained and has the function of encouraging the slipping of the bobbin onto the spindle, as it is well known.

The bobbins are generally loaded from above. As the spindle is rotated, the triangular cam 10, after a rotation through an angle of less than 1200, engages the floating followers 14 and urges them outwards so as to engage the female trilobe 1 f formed in the lower portion of the bobbin 5. The female trilobe, conventional in itself, has been retained.

Accordingly, mechanical engagement between the bobbin 5 and the spindle 3 is obtained.

The clearance of the bores of the floating followers 14 with respect to the dowels 18 is such that, when the triangular cam 10 does not engage the followers, the circle which encompasses the followers has a diameter which is smaller than, or equal to, the diameter d of the female trilobe lf (see Figure 3).

Conversely, as the floating followers 14 are engaged by the cam, the circle which encompasses the followers 14 has the same diameter as the diameter D of the female trilobe lf. When the floating followers 14 are thrust outwards by the triangular cam 10, they snugly fit against the female trilobe If, so that the latter is rotated by the rotation of the spindle.

When the bobbin has collected the required length of yarn, the spindle is automatically stopped by a braking mechanism. Due to the difference in mass between the spindle and the full bobbin (i.e. the cop), the spindle stops a moment before the cop, and thus disengagement of the floating followers 14 from the walls of the female trilobe if takes place. At this time, the cop can be automatically removed and an empty bobbin can be placed on the spindle.

It may be the case that, after removing the cops, the machine is required to run under no-load conditions, for example for adjustment or maintenance, and that, as the empty bobbins are loaded, some of the floating followers may still engage their respective cam surface. In this case, the bobbin placed on the spindle by the automatic bobbin loader does not reach at once its working position, but remains held on the bevelled edges 15 of the floating followers 14. When the spindles are rotated again, the floating followers, due to the rotation of the cam, the weight of the bobbin and the presence of the bevelled edges 15 on the followers (best seen in Figure 7), are urged inwardly between the annular plates 12 and 13, allowing the bobbin to be located correctly. Thereafter, the triangular cam 10 urges the floating followers 14 outwardly again for engaging the trilobe.

Field tests have proved that the selfacting engagement between the female trilobe if and the device shown in Figures 4 to 7 never takes longer than two seconds.

It is apparent that the device of Figures 4 to 7 can be dimensionally adapted to the various textile machines existing in the trade, and this can be effected without any difficulty.

WHAT WE CLAIM IS: 1. In combination, (a) a tubular member having a female trilobe in an end face thereof and (b) a device for providing mechanical engagement between a rotating spindle and the tubular member so that the tubular member can be rotated by the spindle, the device comprising (i) a cam having three cam surfaces, which cam is fixed to, or adapted to be fixed to, the spindle so as to be rotatable therewith, and (ii) a floating cam follower associated with each of the three cam surfaces, the three cam followers being angularly spaced from one another by 1200, the device being such that, upon rotation of the cam relative to the cam followers, each cam surface engages its respective cam follower to cause the cam followers to move radially outwardly to engage the female trilobe of the tubular member.

2. A combination as claimed in claim 1' wherein the diameter of the circle circumscribing the followers, when the followers are not engaged by the cam surfaces of the cam, is less than or equal to the diameter of the circle inscribed in the female trilobe.

3. A combination as claimed in claim 1 or 2, wherein the diameter of the circle circumscribing the followers, when the followers are engaged by the cam surfaces of the cam, is equal to the diameter of the circle which is circumscribed by the female trilobe.

4. A device as claimed in any of claims 1 to 3, wherein the cam followers are provided with bevelled edges.

5. A combination as claimed in any of claims 1 to 4, wherein the tubular member is a bobbin.

6. A combination as claimed in claim 1, substantially as hereinbefore described with reference to, and as shown in, Figures 4 to 7 of the accompanying drawings.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (6)

**WARNING** start of CLMS field may overlap end of DESC **. If, so that the latter is rotated by the rotation of the spindle. When the bobbin has collected the required length of yarn, the spindle is automatically stopped by a braking mechanism. Due to the difference in mass between the spindle and the full bobbin (i.e. the cop), the spindle stops a moment before the cop, and thus disengagement of the floating followers 14 from the walls of the female trilobe if takes place. At this time, the cop can be automatically removed and an empty bobbin can be placed on the spindle. It may be the case that, after removing the cops, the machine is required to run under no-load conditions, for example for adjustment or maintenance, and that, as the empty bobbins are loaded, some of the floating followers may still engage their respective cam surface. In this case, the bobbin placed on the spindle by the automatic bobbin loader does not reach at once its working position, but remains held on the bevelled edges 15 of the floating followers 14. When the spindles are rotated again, the floating followers, due to the rotation of the cam, the weight of the bobbin and the presence of the bevelled edges 15 on the followers (best seen in Figure 7), are urged inwardly between the annular plates 12 and 13, allowing the bobbin to be located correctly. Thereafter, the triangular cam 10 urges the floating followers 14 outwardly again for engaging the trilobe. Field tests have proved that the selfacting engagement between the female trilobe if and the device shown in Figures 4 to 7 never takes longer than two seconds. It is apparent that the device of Figures 4 to 7 can be dimensionally adapted to the various textile machines existing in the trade, and this can be effected without any difficulty. WHAT WE CLAIM IS:

1. In combination, (a) a tubular member having a female trilobe in an end face thereof and (b) a device for providing mechanical engagement between a rotating spindle and the tubular member so that the tubular member can be rotated by the spindle, the device comprising (i) a cam having three cam surfaces, which cam is fixed to, or adapted to be fixed to, the spindle so as to be rotatable therewith, and (ii) a floating cam follower associated with each of the three cam surfaces, the three cam followers being angularly spaced from one another by 1200, the device being such that, upon rotation of the cam relative to the cam followers, each cam surface engages its respective cam follower to cause the cam followers to move radially outwardly to engage the female trilobe of the tubular member.

2. A combination as claimed in claim 1' wherein the diameter of the circle circumscribing the followers, when the followers are not engaged by the cam surfaces of the cam, is less than or equal to the diameter of the circle inscribed in the female trilobe.

3. A combination as claimed in claim 1 or 2, wherein the diameter of the circle circumscribing the followers, when the followers are engaged by the cam surfaces of the cam, is equal to the diameter of the circle which is circumscribed by the female trilobe.

4. A device as claimed in any of claims 1 to 3, wherein the cam followers are provided with bevelled edges.

5. A combination as claimed in any of claims 1 to 4, wherein the tubular member is a bobbin.

6. A combination as claimed in claim 1, substantially as hereinbefore described with reference to, and as shown in, Figures 4 to 7 of the accompanying drawings.