EP0154116B1

EP0154116B1 - Method and apparatus for opening a sliver

Info

Publication number: EP0154116B1
Application number: EP19850100306
Authority: EP
Inventors: Bruce Wayne C/O Allied Corporation Eaddy; James Bryson C/O Allied Corporation Shealy; Robert Pinckney C/O Allied Corporation Rhett; Edward David C/O Allied Corporation Girvan
Original assignee: AlliedSignal Inc
Current assignee: Honeywell International Inc
Priority date: 1984-02-17
Filing date: 1985-01-14
Publication date: 1988-10-12
Also published as: DE3565560D1; JPS60185822A; EP0154116A1; CA1270112A

Description

The present invention relates to a method and apparatus for opening a sliver for dispersion in staple; more particularly it relates to a method and apparatus for opening a sliver comprising fibres, e.g., nylon fibres, some of which are coated with silver, for dispersion in nylon staple.
The use of conductive fibres in yarn to provide antistatic properties is known. Specifically, it is known to utilize silver-coated nylon fibres in nylon yarn to reduce the tendency of the yarn to accumulate static charge. A sliver which includes these fibres is ordinarily broken into smaller pieces for dispersion in nylon staple. By sliver is meant a strand or rope of noncontinuous textile fibres produced by a carding or combing machine and ready for drawing, roving or spinning, etc., and including untwisted or false twisted strand.
Equipment for breaking a sliver, that is for separating it into smaller masses of lower dimensions (length and cross section), for introduction into the staple line is available from Rhone Poulenc and comprises two pairs of rolls. The first pair of rolls are nip feed rolls between which the sliver is fed to a second pair of rolls which are running at a faster speed (up to 25 times the speed of the feed rolls). As the sliver feeds between the second pair of rolls, the speed differential of the pairs of rolls causes the sliver to break off in pieces. Compression of the sliver by the second pair of rolls often causes fibre chunks to break off that have some cross sectional areas as large as that of the original sliver and/or that have a length as large as 6 to 8 inches (15 to 20 cm). These broken pieces of sliver are then aspirated to mix with the air-conveyed staple subsequent to cutting the prior to baling of the staple.
The bale customer (when, for instance, fibres from more than one source are to be combined) ordinarily opens, blends and rebales these initial bales of staple. The staple from several of the blended bales may then be hand fed onto a belt which conveys the staple to a carding roll. Just before entering the carding roll, there normally is an electronic detector which automatically shuts down the carding machinery in response to unacceptable levels of metal which could damage the carding roll. With the silver breaker just described, this occurs with unacceptable frequency when silver-coated nylon fibres are being treated. The present invention was designed to overcome these problems of the prior art, by providing a method and apparatus that could open a sliver without the production of large chunks.
The present invention provides method and apparatus for opening a sliver for dispersion in staple which avoids producing large chunks by avoiding compression of the fibre masses. According to one embodiment, this invention relates to a method for opening a sliver into a plurality of fibre masses, each of smaller dimensions than said sliver, for dispersion of said fibre masses in staple, byfeeding said sliver at a supply speed to a picking unit comprising a plurality of points spaced in and movable in the feeding direction of said sliver, the distance between the ends of successive points in direction of movement being at least 4 mm, and the picking unit being operated such that the ends of said points move at a speed which is at least 290 times the supply speed, whereby the sliver is dispersed into said fibre masses without the exercise of compressive force on said fibres.
According to another embodiment, this invention relates to an apparatus for carrying out such a process comprising a sliver supply means, a picking unit having a plurality of points thereon, spaced in, and movable in feeding direction, and a fibre transport system, the distance between the ends of successive points being at least 4 mm, the picking unit having means for moving said points at a speed at least 290 times the supply speed of said sliver supply means, and said apparatus comprising no means exerting compressive force on said sliver or said fibres after said fibre has reached said picking unit.
The picking roll comprises a plurality of points mounted for rotation about a common axis. The expression "point" as used herein means a member having a pointed free end and extending perpendicular to the sliver. The distance between the free ends of successive points is at least 4 mm, preferably about 5.8 mm. If the distances were less than 4 mm, the sliver would tend to be carried by the points without tearing. The largest distance between successive points is determined by how long the pieces of sliver may be. It is preferred that the distance between the free ends of successive points be no more than 12.5 mm. The supply speed of the sliver being fed to the points may be up to 30 ft/min (0.15 m/s), more preferably from 10 to 25 feet/min (0.051 to 0.13 m/s). The preferred means for feeding comprises a feed roll with at least one associated idler roll, preferably two, with a sliver passing between the feed roll and idler rolls. The feed roll is rotated when the apparatus is operational to feed the sliver into contact with one of the points.
It is preferred that the plurality of points be mounted on the surface of a roll which rotates in the direction of sliver feed. The points may comprise a plurality of needles mounted with their pointed ends out and preferably in a plurality of rows which are substantially parallel to the central axis of the roll. Alternatively, the points may comprise the teeth of at least one band saw blade mounted to the surface of the roll. The blade or blades may be mounted, preferably in grooves, spirally or in rows on the roll surface. When the blades are mounted in rows it is preferred that the rows be substantially perpendicular to the central axis of the roll.
The speed of succession of the plurality of points must be sufficiently faster than the speed of the sliver being fed to the points that the sliver tears without being carried by succeeding points. This corresponds to a surface speed of at least 8900 ft/ min (45 m/s). The most preferred speed is about 9000 ft/min (46 m/s).
The method of the present invention comprises continuously tearing, without compression, the sliver into a plurality of fibre masses, each of smaller dimensions than that of the sliver. The tearing step comprises picking the sliver with the plurality of points in succession and the speed of succession of the plurality of points is sufficiently faster than the speed of the sliver being fed to the points that the sliver tears without being carried by succeeding points. The distance between the free ends of successive points is preferably at least about 4 mm, and the translational speed of each of the points is at least 290 times faster than the speed of the sliver feeding to the points.
The invention is further described with reference to the accompanying drawings, in which:

Figure 1 is a front view, partially cut away, of the sliver opener 10 of the present invention;
Figures 2A and 2B are, respectively, front and side views of roll 20 with needles 21;
Figure 2C is an enlarged view of needle 21 mounted on roll 20; and
Figures 3A and 3B are, respectively, front and side views of roll 20' with teeth 21'.

In the accompanying Drawings, like numbers indicate like apparatus. With reference to Figure 1, side plate 30, which is welded to base plate 31, supports extension plate 15, the conventionally mounted feed roll 16 with associated idler rolls 17 and 17', and roll housing 22. Extension plate 15 has a central hole for seeding funnel 14. Funnel 14 is located in plate 15 by means of an exterior tab (unshown) with a hole through which fits a locating pin (unshown) extending from plate 15. The sliver exit end of funnel 14 preferably is canted up to 15° towards feed roll 16. Feed roll 16 is driven by motor 18 to rotate in the direction of the arrow. Associated idler rollers 17 and 17' are spring loaded to urge upward and in contact with sliver 11 which passes between each of the idler rollers and feed roll 16. Roll 20 is mounted in housing 22 on a shaft (unshown), the other end of which is conventionally mounted to a gear belt pulley which, in turn, has a gear belt driven by a second motor 19. Rotation of roll 20 in housing 22 is counter clockwise (as seen from the viewpoint of Figure 1). The base of roll housing 22 opens into tube 23 for evacuation of sliver particles. Tube 23 passes through an opening in base plate 31 to intersect with air-conveyed staple line 25. Air is injected into tube 23 at 24 to help evacuate the sliver particles from tube 23 and housing 22. The sliver particles are aspirated to mix with staple in line 15.
Figures 2A to 2C depict roll 20 with needles 21 pressed therein with the sharper pointed end sticking straight out. In Figure 2A a single row of needles 21 is shown. It is preferred that there be a plurality of rows, which preferably are parallel to the central axis of roll 20, and the shortest distance between the tips of successive rows of needles 21 is at least 4 mm. It is preferred, although not critical, that needles 21 be placed directly behind one another in succeeding rows; in this instance, the distance between the tips of successive rows of needles 21 will be the actual distance between needles in the two rows. The most preferred roll 20 having needles 21 thereon is characterized as follows: The roll has an outer diameter of 117 mm, a roll surface width of 22.3 mm, 63 rows of needles, 19 needles per row, rows equispaced 5.81 mm centre to centre. The 19 needles per row are equispaced within the row and rows of needles are not staggered, but lined up one behind the other. The individual needles extend 4.0 mm from the roll surface. Needles 21 could, of course, be offset in their rows, greater or fewer in number, as desired: The needles could also be angled, the key being that they pick the sliver 11 when it comes into contact therewith.
Figures 3A and 3B depict an alternate picking roll 20' with teeth 21'. A groove was precut to spiral around the surface of roll 20'. A band saw blade was placed into the groove with the set screw (unshown) holding the blade from a side of roll 28' at its starting and terminating points. The blade has a plurality of teeth 21' extending outwardly therefrom. In the embodiment depicted, the dimensions of roll 20' are identical to those of roll 20 in Figures 2A and 2B. The blade extends 4.0 mm from the surface of roll 20, 2.0 mm being the extension of teeth 21' from the body of the blade. As shown in Figure 3B, teeth 21' are canted approximately 9° in the direction of rotation.
With reference to Figure 1, sliver opener 10 operation is as follows. Sliver 11 is fed through inlet 13 in the top back side of opener 10. Housing/ cabinet 12 is opened and sliver 11 is pulled through by hand. Sliver guide funnel 14 is removed and sliver 11 is hand fed through the funnel, allowing approximately 0.75 inch (1.9 cm) to extend past the exit end of funnel 14. Funnel 14 is placed on extension plate 15 and cabinet 12 is closed. Electrical leads (unshown) are plugged into the control cabinet for the tow cutter (all unshown) upstream of air-conveyed staple line 25. Motor 19 is cut on to start rotation of roll 20. Roll 20 rotates at least at 6000 revolutions per minute (rpm), which is approximately 8900 ft/min (45 m/s) based on a roll diameter calculated from end of pin to end of pin. It is preferred that roll 20 rotate at 6800 rpm, or about 9000 ft. min (46 m/s), since at 6000 rpm sliver 11 occasionally wraps around roll 20. Feed roll 16 may be set to rotate at up to 30 ft/min (0.05 to 0.13 m/s). Feed roll 16 with associated idlers 17 and 17' pulls sliver 11 from the exit end of funnel 14 and guides it into one of needles 21 on roll 20 (or teeth 21' of roll 20'). Rotation of roll 20 and needles 21 tears sliver 11 into very small fibre masses (of smaller dimensions than sliver 11), and slings these sliver particles through the opening in the base of roll housing 22 into air injected tube 23 which carries the particles to be mixed with nylon staple in air-conveyed staple line 25 for subsequent baling.
The electrical setup is such that motor 19 must be started before feed roll motor 18. In the event sliver 11 becomes entangled or wraps on roll 20 (or 20') and jams, a current-monitoring relay (unshown) attached to motor 19 shuts off the power. Feed roll motor 18 is interlocked with the cutter (unshown). When the cutter is cut off, feed roll motor 18 is also shut off.
Although needles 21 and teeth 21' have been depicted and described as the plurality of points, other types of openers could readily be used as long as sliver 11 is picked to tear without compression. Individual filament lengths within the sliver should be sufficiently short to prevent wrapping around roll 20 or 20' when sliver 11 is picked. With rolls of the described size, a maximum length of about 5 inches (13 cm) is satisfactory.

Claims

1. A method for opening a sliver into a plurality of fibre masses, each of smaller dimensions than said sliver, for dispersion of said fibre masses in staple, by feeding said sliver at a supply speed to a picking unit comprising a plurality of points spaced in and movable in the feeding direction of said sliver, characterized in that the distance between the ends of successive points in direction of movement is at least 4 mm, and in that the picking unit is operated such that the ends of said points move at a speed which is at least 290 times the supply speed, whereby the sliver is dispersed into said fibre masses without the exercise of compressive force on said fibres.

2. A method according to claim 1 characterized in that the supply speed is up to 30 feet per minute (0.15 m/s), and the speed at which the points are moved is at least 8900 feet per minute (45 m/s).

3. A method according to claim 1 or 2 characterized in that the points are mounted on the surface of a roll.

4. Apparatus for carrying out a process according to claim 1 comprising a sliver supply means (14,15,16,17,17'), a picking unit (20, 20') having a plurality of points (21, 21') thereon, spaced in, and movable in the feeding direction, and a fibre transport system (23, 24, 25), characterized in that the distance between the ends of successive points (21, 21') is at least 4 mm, in that the picking unit has means for moving said points at a speed at least 290 times the supply speed of said sliver supply means, and in that said apparatus comprises no means exerting compressive force on said sliver or said fibres after said fibre has reached said picking unit.

5. Apparatus according to claim 4 characterized in that said supply means is adapted to deliver a sliver at a supply speed of up to 30 feet per minute (0.15 m/s), and in that said picking unit is adapted to move said points, at a speed of at least 8900 feet per minute (45 m/s).

6. Apparatus according to claim 4 or 5 characterized in that said picking unit comprises a roll (20) having a plurality of needles (21) mounted thereon.

7. Apparatus according to claim 4 or 5 characterized in that said picking unit comprises a roll (20') with at least one band saw blade having teeth (21') mounted thereon.