US2958177A - Cordforming - Google Patents

Description

Nov. 1 1960 L. SEIDL CORDFORMING Filed April 14, 1958 INVENTOR. LQI S SE! D L 2,958,177 c Patented Nov- 1, 9

CORDFQRMING Lois Seidl, Arnhem, Netherlands, assignor to American Erika Corporation, Enka, N.C., a corporation of Delaware Filed Apr. 14, 1958, Ser. No. 728,357

Claims priority, appllication Netherlands Apr. 23, 1957 12 Claims. (Cl. 57-585) The present invention relates to cordforming in general and more particularly to single spindle cordforming machines which utilize cooperating pairs of braked rollers for tensioning individual singles being plied together.

One cordforming machine of the type mentioned above is shown and described in application Serial No. 364,174, dated June 25, 1953, which is owned in common with this case. That machine consists essentially of a rotatably mounted hollow spindle having a lateral thread discharge opening and a thread storage disc adjacent thereto and extending outwardly therefrom. A package support is rotatably mounted above and coaxially with the hollow spindle, the relative movement being provided so that rotation of the spindle will not affect the stationary disposition of a package placed on the support.

Thread fed from this package, which will be referred to hereinafter as the internal thread, for reasons to appear, is tensioned and then combined with another thread in a cording zone above the upper package. A second package is mounted beneath the hollow spindle and supplies what will be referred to hereinafter as the external thread through the hollow spindle, outwardly through the discharge opening, over the thread storage disc, and around the upper package in the form of a balloon upon rotation of the spindle. This external thread is tensioned prior to passage through the hollow spindle. Suitable thread guides of course are provided to insure proper passage of the threads from the respective supply packages to the cording zone, as well as from the cording zone to a suitable collection device.

The tension in the thread ballooning around the upper package is maintained substantially constant by the use of the thread storage disc connected to the hollow spindle. In order to obtain uniform twist in the cording zone, however, it is necessary that thread be supplied to the disc under a predetermined tension which does not vary, or which varies very slightly only. The tension in the internal thread should balance, if possible, the tension in the ballooning external thread, or the component threads in the cord will not have the same length when the tension therein is released. It is evident that the singles making up the cord should have equal lengths in order that a load applied to the resulting cord will be divided equally. Although the storage disc compensates for variations in tension on the external thread (as explained in aforesaid application Serial No. 364,174), this disc has no effect on fluctuations in tension on the internal thread, since the latter thread does not contact this disc. High demands, therefore, are placed on the tensioning device for the internal thread, or internal tensioning device, in order to prevent the occurrence of fluctuations in tension. It has been found that a tensioning device of the type described in application Serial No. 532,920, filed September 7, 1955, which on February 3, 1959, matured to US. Patent No. 2,872,128, operates very effectively for this purpose. This tensioning means consists in a pair of cooperating freely rotatable rollers, or gears, preferably wheels having meshing teeth, and means for applying a constant braking force, or resistance to rotation, to one of the pair.

In the past it was thought that satisfactory tensioning of the external thread could be accomplished by passing this thread in a serpentine fashion over one or more fixed surfaces. These devices have an advantage of simple construction, and actually effectuate a sufficiently high and uniform tension in the external thread. In a commercial application of this type external tensioning device to a single spindle cording machine, however, it was found that the cord obtained thereby was fibrous, or had broken filaments extending therefrom. Since this condition is undesirable in cord construction, the fixed external tensioning device had to be discarded,

Further experimentation indicated that the aforesaid fibrous characteristic in the cord could be overcome by the use of the internal tensioning rollers described earlier for tensioning the external thread, with this thread pass ing in an are over the rollers before entering the hollow spindle. A new problem arose, however, upon use of a pair of cooperating, braked, rollers in this manner. It was found that upon the occurrence of tension variations in the external thread supplied to this tensioning device, the thread would run off the end of the braked rollers. This lateral shifting of the external thread results from a rolling force or torque generated as the hollow spindle twists this thread during ballooning around the upper package. If a constant tension is maintained on the external thread, the resistance offered by the tensioning rollers will counteract the twist torque imparted by the spindle.

When the external thread runs off the tensioning rollers, it becomes soiled and very often becomes fibrous by the breaking of outer filaments. Moreover, the tension imparted by the tensioning rollers is abruptly discontinued with the result that non-uniform twist occurs in the cording zone and the cord produced will consist of singles having unequal lengths. Any load applied to this cord of course will not be distributed equally, and the cord will have a lower overall strength than cord produced under uniform conditions. Further, the external thread could become wedged between one or both of the tensioning rollers and its supporting shaft and cause an entanglement which would require considerable time to repair.

The obvious solution to the problem enumerated above would appear to involve no more than the placing of a suitable guide adjacent to the tensioning rollers in order to prevent lateral movement of the external thread when fluctuations in tension occur. While this certainly would prevent thread run-off, it would not indicate to the machine operator when there had been a change in thread tension. In other words, a variation in thread tension sufficient to cause run-off could occur and there would be no apparent change in operation of the cordforming machine. Nothwithstanding this apparent normal operation, the machine in the meantime would be producing cord from singles which were non-uniformly tensioned, with the resulting product being inferior for reasons previously mentioned. 7

An important object of this invention, therefore, is to provide a modified external thread tensioning device not having the disadvantages of known means.

Another object of the present invention is to provide a device which will discontinue the cording operation upon occurrence of fluctuations in tension on the external thread.

A further object of this invention is to provide a device which will terminate the cording operation immediately upon occurrence of conditions which heretofore embodiment,

' In accordance with the present invention, the external thread supplied to a single spindle cording machine is wrapped in an are over the periphery of one of a pair of cooperating, braked rollers, of the type described, prior to passage into the rotatable hollow spindle of the cording machine. The thread discharge portion of the rollers is disposed adjacent to the entrance of the hollow spindle, and the axes of the rollers are substantially perpendicular to the axis of the spindle. Adjacent to that end of the thread discharging roller to which the twist torque'imparted by the spindle is directed, a knife blade is suitably mounted so as to contact and sever thread which runs off the tensioning roller.

During operation of a cordforming machine equipped in the manner specified, external thread which previously would have produced inferior cord runs off the tensioning roller and immediately thereafter is severed by the knife blade. That portion of the external thread which has already passed into the hollow spindle is hurled to the outside thereof by centrigufal force acting on the balloon. This not only prevents the formation of poor quality cord, but also prevents entanglements due to Winding of the thread about the rollers or their supporting shafts and consequent retraction of that thread in the spindle and balloon, which thread could be wound around the rotating spindle before detection of the malfunction.

Although the thread tensioning rollers may be provided with smooth, grooved or toothed surfaces, the most constant grip on the thread is obtained if the same is guided between cooperating toothed wheels. Furthermore, it is preferred that the tensioning rollers be supported in cantilever fashion, or from one end only. This arrangement facilitates threading-in and also the knife blade mounting. It is evident, of course, that the twist imparted by the rotating hollow spindle should be directed to the unsupported end of the rollers if this is where the knife blade is to be located. The direction of twist torque of course is determined by the type of twist (S or Z) being imparted to the external single.

Considering the variables mentioned above, preference is given to an external thread tensioning device wherein the tensioning rollers or wheels are positioned immediately adjacent to the hollow spindle entrance, each roller being provided with intermeshing teeth, with the first or thread receiving roller being directly braked and the second or thread discharge roller being indirectly braked through the intermeshing teeth. It is also preferred that the discharge portion of this Second roller lie diametrically opposite to the intermeshing zone between the two rollers, facing, of course, the hollow spindle, and that the axes be perpendicular to the spindle axis, and that the rollers be supported from one end only, for example, with stub shafts. The twist torque imparted by the spindle, in this case, must be directed toward the free end of the rollers, at which endthe knife blade should be mounted, preferably with the cutting edge thereof extending beyond the connecting line between the intermeshing zone and entrance to the spindle opening.

The most satisfactory cutting action is obtained if the cutting edge is mounted as nearly as possible to the periphery of the tensioning roller. An advantageous arrangement is such that the cutting edge converges with the axis of the thread discharge roller in the direction away from the same. An optimum cutting angle has been found to be 70 between the cutting edge and the roller axis. The cutting action is further facilitated if a guiding mem- 2,95s,177 V r I ber is provided between the cutting edge and the side of the discharge roller, with the edge of the guiding member converging under a smaller angle than that between the cutting edge and roller axis.

By the use of the guiding member mentioned, the distance from the cutting edge of the knife blade to the connecting line between the intermeshing zone and the entrance to the spindle opening is increased, this increase benefitting the cutting action of the knife blade. The cutting action is even further improved if guide rods are mounted on both sides of the cutting edge at a distance equal to the diameter of the thread being corded. These rods serve as counter knives, preferably being placed at an angle of from 10 to 30 with respect to the cutting edge, and press the thread which runs off the roller against the knife blade.

One embodiment of the apparatus according to the present invention will now be described, with particular attention directed to the accompanying drawings, wherein Figure 1 represents an elevational view, partly in section, of a single spindle cordforming machine to which this invention is particularly adaptable, and

Figure 2 is a perspective view showing the external thread tensioning rollers of Figure l on an enlarged scale, and the disposition of the knife blade and guiding member with respect thereto.

The cordforming machine generally indicated by reference numeral 10 in Figure 1 comprises a hollow rotatable spindle 11 suitably supported in an upright, slightly inclined, position by means not shown, a thread tensioning or storage disc 12 secured to or formed integral with said spindle for rotation therewith, and a belt pulley 13 through which rotation is imparted to the spindle by conventional means, also not shown. Mounted above and coaxially with hollow. spindle 11 is a package support or stator 14. This support is rotatable relative. to the spindle 11 and remains 1 substantially stationary during rotation of the latter, by virtue of the inclined axis and a suitably positioned counterweight, as fully explained in aforesaid application Serial No. 364,174.

An upper or internal thread package 15 is positioned on package support 14 and internal thread 16 is withdrawn axially from this package and passed around internal tensioning rollers 17 to the cording zone generally indicated at 18. The internal tensioning rollers may be of the type described in said Patent No. 2,872,128. A hood 20, preferably transparent, surrounds the upper package and prevents contact between the individual singles prior to passage into the cording zone. A cover plate 21 for the hood 20 is suitably apertured whereby internal thread 16 may be passed from the package to the internal tensioning rollers. This hood may support the internal tensioning rollers, if desired.

Mounted on a stationary support beneath the cordforming machine 10 is an external or lower thread package 22, from which external thread 23 is withdrawn axially in a manner to be explained. This external thread passes through thread guide 24 and over the external tensioning rollers 25 prior to passage into and through the hollow spindle 11. A radial opening 26 in storage disc 12 communicates with the axial opening in the spindle, and external thread 23 is threaded therethrough. This thread next passes around the storage disc for approximately one complete turn and balloons outwardly around the hood 20 which surrounds the internal package 15. This ballooning is produced by centrifugal force and of course occurs only when the spindle 11 is rotated through the belt pulley 13. The external thread passes from the balloon into the cording zone 18 at which'position it is wrapped around and therefore combined with internal thread 16 to produce cord 27. The cord 27 is withdrawn through thread guide 28 by a suitable cord collection device (not shown). The tensions applied by the internal and external tensioning devices'may be adjusted in order to vary the cording point within the cording zone between thread guide 28 and game pin 30, over which internal thread 16 is passed to efiectuate more complete wrap about the internal tensioning rollers.

Inasmuch as internal tensioning rollers 17 are identical to external rollers 25 insofar as concerns tensioning, only the latter group has been shown in Figure 2 for further illustration of this invention.

The external tensioning device 25 comprises a thread receiving toothed wheel 31 and a thread discharge toothed wheel 32. The teeth of these wheels loosely intermesh at zone 33. As a result of this loose engagement, thread knots which occasionally are necessary may pass through the zone without binding. The thread discharge wheel 32 is freely rotatable about fixed shaft 34 and the thread receiving wheel 31 is fixed on rotatable shaft 35. The receiving wheel 31 may be directly braked in a known manner (not shown), for example magnetically, and thread discharge wheel 32 of course is indirectly braked by virtue of the intermeshing relationship with wheel 31.

The external tensioning device 25 is so positioned with respect to the hollow spindle 111 that the thread discharge point 36, which lies diametrically opposed to the intermeshing zone 33, faces the entrance or supply opening 37 in the spindle. External thread 23 is passed from package 22 over the thread receiving wheel 31 by the use of thread guide 38 which is spaced from the wheel, and a second thread guide 40 which is aligned with a tangent between the intermeshing wheels. The thread 23 therefore is fed vertically downwardly into the intermeshing zone 33, after which it passes in an arc over the periphery of wheel 32 and leaves the same at discharge point 36, which is in alignment with the axis of spindle 11.

Adajcent to the free or unsupported end of thread discharge roller 32, and on the lower side thereof, knife blade 41 is mounted. The plane of this blade extends generally perpendicular to the plane of rotation of wheel 32 and the cutting edge 42 forms an angle of approximately 70 with respect to the axis 34 of this wheel. Guiding portion 43 of the knife blade, which makes an angle of 15 with the axis 34, spaces or bridges the gap between the cutting edge 42 and the side of wheel 32. Guide rods 44, 45 are mounted on opposite sides of the cutting edge, and are spaced slightly therefrom. These rods serve as counter-knives and force thread which has run off the wheel 32 against the cutting edge of knife blade 41. Rods 44, 45 make an angle of 20 with respect to the cutting edge 42. The knife blade and guide rods may be supported from the fixed shaft 34, if desired, or in any other suitable manner, as from the cordforming machine frame.

During operation of the cordforming apparatus described above, external thread 23 does not travel over wheel 32 in a plane normal to shaft 34 as might be expected but, instead, travels in a plane inclined toward the unsupported end thereof. Upon rotation of spindle 11, and that portion of the external thread contained therein, a twist torque is generated between storage disc 12 and the intermeshing zone 33, which torque urges the thread laterally of the toothed wheel into the inclined path mentioned. The direction in which the twist torque urges the thread of course is determined by the direction of rotation of spindle 11 and the particular end from which the toothed wheels are supported, as explained hereinabove. During normal operation, this twist torque is not sufiicient to shift the external thread completely off the end of toothed discharge wheel 32.

If, however, a disturbance occurs in the ballooning portion of external thread 23, which could be caused, for example, by filament rupture and consequent decrease in thread tension, the twist torque will no longer be counteracted by the tension imparted at wheels 31, 32, and the thread 23 will migrate to the unsupported end of roller 32 and thereafter run off the same. Immediately upon running off this wheel, however, the thread will engage the guiding portion 43 of knife blade 41 and thereafter will become severed, which of course discom tinues the cording operation. In the event that rupture occurs in the balloon, the thread 23 will be wedged between the cutting edge 42 and the guide rods 44, 45, since that portion of thread within spindle 11 is twisted even after balloon breaking, which results in a shortening of the thread between the opening 26 in storage disc 12 and the intermeshing zone 33, and subsequent run-01f. If the decrease in thread tension is not caused by thread break or rupture, the balloon tension will cause the thread to wedge between the cutting edge and guide rods,.which of course will result in thread severance.

After thread severance, that portion remaining in hollow spindle 11 will be hurled outwardly through-opening 26 due to continued rotation of the spindle. This results in a very effective clearing of the external tensioningdevice, spindle and storage disc from any thread remnants which could give rise to malfunctioning'of the cordforming machine.

Inasmuch as many alternatives will become apparent to those skilled in this art, it is intended that the scope of this invention be limited only to the extent set forth in the following claims.

What is claimed is:

1. A cordforming machine comprising a rotatable hollow spindle receiving thread to be corded, a tensioning device for guiding thread to said spindle, a knife blade, and means supporting said knife blade outwardly of and stationary with respect to one end of said tensioning device to effectuate severance in the event thread runs off that end of said tensioning device.

2. The machine as set forth in claim 1 and further comprising means for guiding said thread into contact with a cutting edge of said knife blade in the event of thread run-off.

3. In a cordforming machine having a rotatable hollow spindle receiving thread to be corded and a tensioning device for guiding thread thereto, said tensioning device consisting of a thread receiving roller, a thread discharge roller and means for guiding thread between said rollers and in an are around the periphery of said discharge roller, the improvement comprising a knife blade mounted adjacent to one end of said thread discharge roller, the plane of said blade extending generally perpendicular to the plane of rotation of said rollers.

4. The improvement as set forth in claim 3 and further comprising guide rods mounted on opposite sides of said knife blade.

5. The improvement as set forth in claim 3 wherein the cutting edge of said blade forms a line which converges with the axis of said discharge roller in a direction away from the tensioning device.

6. The improvement as set forth in claim 5 wherein the cutting edge makes an angle of 70 with the axis of said discharge roller.

7. The improvement as set forth in claim 4 and further com rising a guiding edge extending between the cutting edge of said knife blade and one side of said discharge roller, said guiding edge converging under a smaller angle than that between the cutting edge and the roller axis.

8. The improvement as set forth in claim 3 and further comprising guide rods mounted on opposite sides of said knife blade, said rods being spaced from said blade a distance equal to the diameter of the thread being corded and extending at an angle of from 10 to 30 with the cutting edge of the knife blade.

9. A tensioning device comprising a thread receiving toothed wheel, a thread discharge toothed wheel intermeshing with said thread receiving wheel, means for guiding thread into an intermeshing Zone between said wheels and in an are around the periphery of said discharge wheel, and cutting means mounted adjacent to and extending away from one end of said discharge wheel,

10. A cordforrning machine comprising an internal thread package, means for tensioning thread which is withdrawn from said internal package and led to a cord ing zone, an external thread package, means for ballooning thread withdrawn from said external package around the internal thread in said cording zone, intermeshing toothed Wheels for tensioning thread withdrawn from said external thread package, a knife blade mounted adjacent to one end of said toothed wheels, and means for guiding cord away from said cording zone.

11. In a cordforming machine having an internal thread package, means for guiding thread withdrawn from said internal package to a cording zone, an external thread package, means for ballooning thread withdrawn from said external package around the internal thread in said cording zone, and means for withdrawing cord from said cording zone, the improvement consisting of means for tensioning thread Withdrawn from both said internal and external packages, at least one of said tensioning means comprising cooperating thread receiving and thread discharging wheels, and a knife blade mounted adjacent one end of said wheels for severing thread running ofi the ends thereof.

12. A thread tensioning device comprising a thread receiving wheel, a thread discharge wheel mounted in engagement with said receiving wheel for cooperation therewith, means for guiding thread into a tension zone between said wheels and into contact with said discharge wheel, and a knife blade mounted adjacent to and extending away from one end of said discharge wheel, whereby thread running oil the end of said discharge wheel will be immediately severed.

References Cited in the file of this patent UNITED STATES PATENTS

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