Background Currently, the fiber industry typically measures physical properties of wool fibers in bulk form. By"bulk form"it is meant that many wool fibers, such as in a toe, are measured at the same time and the properties of the toe are ascribed to the individual fibers.

It may be more accurate, at times, to measure the properties of individual wool fibers, rather than to take bulk measurements. However, wool fibers tend to be very difficult to individualize. One reason for this is that wool fibers are comparatively longer than many other fibers. Thus, wool fibers are difticult to handle and are easily broken when individualized. These and other difficulties have caused the wool industry to predominantly use bulk measurements, rather than individual measurements.

It would therefore be desirable to have an apparatus for individualizing long fibers contained within a feed stream of wool, which will not break the wool fibers during individualizing.

Summary The above and other needs are met by an apparatus that individualizes fibers within a feed stream without breaking the fibers. A first stage, having first pinch rollers, receives the feed stream and provides it to a second stage. The second stage receives the feed stream from the first stage, and provides a thinned stream to a third stage. Second stage apron belts draw the feed stream under tension from the first stage into the second stage. Second pinch rollers draw the feed stream under tension from the second stage apron belts and provide the thinned stream to the third stage. The third stage receives the thinned stream from thc second stage and provides individualized fibers. Third stage apron belts draw the thinned stream under tension from the second stage into the third stage. Third pinch rollers draw the thinned stream under tension from the third stage apron belts and provide the individualized fibers.

The first, second, and third pinch rollers act as constant speed stages, in which the fibers are maintained at a constant speed for the entire time during which they are held by these pinch rollers. The second and third stage apron belts act as variable speed stages which transport and apply an acceleration force to each fiber, and then accelerate the fiber individually when the fiber's trailing end passes from the immediately preceding pinch roller, and which allow a fiber to further accelerate when the leading end of the fiber is acquired by the next pinch roller. Thus, fibers between the apron belts may be moving at any one of three different speeds. By successively thinning the feed stream through each of the three stages, the feed stream is reduced from a toe of fibers to individualized fibers. The individualized fibers can be drawn off one at a time to an analyzer, where they are measured for physical characteristics, such as length, color, or strength. Thus, the present invention allows such measurements to be made on fibers individually, and thus reduces the inaccuracies which may be inherent in making the measurements on the toe in bulk form.

In the preferred embodiment, second platens and third platens are disposed adjacent the second stage apron belts and third stage apron belts respectively. The platens provide pressure on the feed stream and thinned stream, and allow the fibers to slip to a controlled degree. Most preferably, at least one each of the second platens and third platens is a pressure platen, for adjusting the pressure on the feed stream between the second stage apron belts and the thinned stream between the third stage apron belts.

Stepper motors drive each of the first, second, and third pinch rollers and the second and third stage apron belts, and a speed control separately controls the rotation rates of each. The first pinch rollers rotate at a rate of about 5 rpm, the second stage apron belts rotate at a rate of about 15 rpm, the second pinch rollers rotate at a rate of about 30 rpm, the third stage apron belts rotate at a rate of about 60 rpm, and the third pinch rollers rotate at a rate of between about 300 rpm and about 400 rpm.

A vacuum nozzle is disposed adjacent the third stage, for drawing individualized fibers from the third stage with a non-turbulent air flow. An analyzer receives the individualized fibers from the vacuum nozzle, and detect physical properties of the individualized fibers, such as length.

The first, second, and third stages and the vacuum nozzle are adjustably mounted to a track, for increasing and decreasing gaps between the first, second, and third stages and the vacuum nozzle. There is a first gap of between about one-half inches and about four and one-half inches between the first and second stage, a second gap of between about one-half inches and about six and one-half inches between the second and third stages, and a third gap of between about zero inches and about one-quarter inches between the third stage and the vacuum nozzle.

First adjustable pressure means adjust the pressure between the first pinch rollers, and prevent the fibers within the feed stream from slipping between the first pinch rollers.

Similarly, second adjustable pressure means adjust the pressure between the second pinch rollers, and prevent the fibers within the thinned stream from slipping between the second pinch rollers. Likewise, third adjustable pressure means adjust the pressure between the third pinch rollers and prevent the individualized fibers from slipping between the third pinch rollers.

Second air knives disposed adjacent the second pinch rollers, and third air knives disposed adjacent the third stage apron belts, remove fibers from the second pinch rollers and the third stage apron belts respectively. Preferably, the fibers are wool and the feed stream is toe.

In a method for individualizing fibers within a feed stream, without breaking the fibers, the feed stream is provided to first pinch rollers that are rotating at a given speed.

The pressure between the first pinch rollers is increased until the fibers of the feed stream do not slip between them. The fibers are drawn under tension from the first pinch rollers and between a second upper and a second lower apron belts, which are rotating at a speed greater than the speed of the first pinch rollers. The pressure on the fibers between the second stage apron belts is adjusted to allow a controlled degree of slip between the fibers.

The fibers are drawn under tension from the second stage apron belts to second pinch rollers that are rotating at a speed greater than the speed of the second stage apron belts.

The pressure between the second pinch rollers is increased until the fibers do not slip between the second pinch rollers.

As before, the fibers are drawn under tension from the second pinch rollers between a third upper and a third lower apron belts, which are rotating at a speed greater than the speed of the second pinch rollers. The pressure on the fibers between the third stage apron belts is adjusted to allow a controlled degree of slip between the fibers. In a manner similar to that explained above, the fibers are drawn under tension from the third stage apron belts to third pinch rollers, which are rotating at a speed greater than the speed of the third stage apron belts. The pressure between the third pinch rollers is increased until the fibers do not slip between the third pinch rollers. The fibers are released from the third pinch rollers as individualized fibers.

The method described individualizes fibers by drawing them into each successive stage at ever increasing rates of speeds. As the fibers pass through alternate sets of pinch rollers and apron belts, those fibers that are slightly ahead of other fibers in the feed stream, or in other words, those fibers that enter each set of rollers or belts prior to other fibers in the feed stream, are drawn ahead of the fibers behind it. In this manner the feed stream is quickly drawn and thinned to the point that individualized fibers are produced.

Brief Description Of The Drawings Other objects, features and advantages of the present invention will become apparent by reference to the following detailed description when considered in conjunction with the accompanying drawings, which are not to scale, wherein like reference numbers refer to like elements throughout the several views, and wherein: Fig. 1 is a functional diagram of an apparatus of the present invention, and Fig. 2 is a partial perspective view of the apparatus of the present invention.

Description Of The Preferred Embodiments Shown in Fig. 1 is an individualizer 50 for individualizing fibers contained within a feed stream 9 without breaking the fibers. Preferably, the feed stream 9 is a toe of wool, but it could also be a sliver of cotton or some other fibrous material. The fibers of the feed stream 9 are substantially parallel within the feed stream 9, but are not aligned as to where they begin or end within the feed stream 9. In other words, the fibers overlap one another along their length within the feed stream 9, such that the feed stream 9 is a long cord of unwoven fibers. Further, the fibers of the feed stream 9 are not substantially twisted together, as are the fibers of a rope. Thus, it is primarily the friction between the individual fibers within the feed stream 9 that keeps the feed stream 9 together in a long cord.

A first stage 10 receives the feed stream 9 into the individualizer 50. In the preferred embodiment the first stage 10 has a fixed position. However, in an alternate embodiment the first stage 10 is adjustably mounted on a track 52 (depicted in Fig. 2), such that the first stage 10 can be moved and releasably affixed along the length of the track 52.

This may be accomplished in any one or more of several different ways.

For example, the track 52 may comprise one or more straight bars, either square or circular in cross-section, and the first stage 10 has clamps designed to fit around the bars.

The clamps are loosened so that the first stage 10 can slide and be adjusted in position along the length of the bars, and then the clamps arc tightened to aftix the first stage 10 in the desired position. Alternately, the track 52 could be one or more lead screws, with the bearing portions of the lead screws attached to the first stage 10. The lead screws of the track are then rotated to move the first stage 10 forward or backward along the track 52, and the first stage 10 is then held in place by the threads of the lead screws when they are no longer rotated, thus affixing the first stage 10 in place. Further, the track 52 may be onc or more toothed rails which mesh with gears attached to the first stage 10. The gears may be motorized to advance the first stage 10 back and forth along the length of the track 52.

The internal resistance of the motors may then keep the first stage 10 in the desired location. Of course, any combination of these methods may also be used to affix the first stage 10 to the track 52, and many other methods and devices could also be readily adapted, and are within the spirit of this disclosure.

The first stage 10 includes first pinch rollers 16a and 16b, for drawing the feed stream 9 into the first stage 10. As used herein the designations such as"first,""second," or"third"do not necessarily indicate how many of an element may be present in an embodiment, but rather tend to indicate the stage in which the clement is disposed.

Preferably, one of the first pinch rollers 16a and 16b is rubber and the other is stainless steel. However, in alternate embodiments, both of the first pinch rollers 16a and 16b are either rubber or some other elastomeric material, or stainless steel or some other hard material. The first pinch rollers 16a and 16b may be ribbed along their length to provide increased surfaces and edges for friction between the first pinch rollers 16a and 16b and the fibers of the feed stream 9 which pass between them.

First adjustable pressure means 56a (depicted in Fig. 2) are used to adjust the pressure between the first pinch rollers 16a and 16b. The first adjustable pressure means 56a may be provided by one or more of several different mechanisms. For example, the ends of the first pinch rollers 16a and 16b may each be mounted to a screw, with one end of the upper first pinch roller 16a at one end of the screw, and the corresponding end of the lower first pinch roller 16b at the other end of the screw, with a similar configuration at the other ends of the first pinch rollers 16a and 16b. In this manner, when the screws are rotated in one direction, the first pinch rollers 16a and 16b are drawn toward one another, and when the screws are rotated in the other direction the first pinch rollers 16a and 16b are pushed apart from each other.

As another example, one of the first pinch rollers 16a and 16b may be placed in an affixed position and the other of the first pinch rollers 16a and 16b may be adjustable toward and away from the affixed roller. This may be accomplished by mounting one of the first pinch rollers 16a and 16b on thumb screws, which can be adjusted to move the first pinch roller 16a or 16b back and forth. Further, pressurized cylinders, either hydraulically or pneumatically powered, may be attached to the movable first pinch roller 16a or 16b, to provide the pressure between the first pinch rollers 16a and 16b. Of course, there are several other devices which may also be employed to provide pressure between the first pinch rollers 16a and 16b, which other devices are contemplated by the invention and are within the scope of this disclosure.

The materials from which the first pinch rollers 16a and 16b are formed are selected in part on their ability to firmly grasp and provide friction to the fibers of the feed stream 9. The adjustable pressure between the first pinch rollers 16a and 16b is also provided, in part, to enhance the ability of the first pinch rollers 16a and 16b to provide friction to the fibers of the feed stream 9. In this manner, the fibers of the feed stream 9 preferably do not slip between the first pinch rollers 16a and 16b. By this it is meant that the fibers of the feed stream 9 will preferably retain their position relative to one another along the length of the feed stream 9 for the entirc time that they are engaged between the first pinch rollers 16a and 16b. The importance of retaining the fibers of the feed stream 9 between the first pinch rollers 16a and 16b such that they cannot slip past one another is described in greater detail below.

The first pinch rollers 16a and 16b are rotated at the same speed and in opposing directions, so that the feed stream 9 placed between them is drawn between the first pinch rollers 16a and 16b and ejected out from between the first pinch rollers 16a and 16b on the other side. A stepper motor 54 (depicted in Fig. 2) provides the rotation for the first pinch rollers 16a and 16b, and a speed control 42 (depicted in Fig. 2), in communication with the stepper motor 54, controls the speed at which the first pinch rollers 16a and 16b rotate.

The first pinch rollers 16a and 16b rotate at a first given speed, which in the preferred embodiment is about 5 rotations per minute (rpm). The significance of this speed is described in greater detail below.

A second stage 12 is disposed adjacent the first stage 10, and is also mounted on the track 52 (depicted in Fig. 2) in a manner similar to that described above in great detail for the first stage 10. The second stage 12 receives the feed stream 9 from the first stage 10, and provides a thinned stream 13. Second stage apron belts 18a and 18b receive the feed stream 9, and draw the feed stream 9 under tension between the second stage apron belts 18a and 18b. The second stage apron belts 18a and 18b are preferably an elastomeric material such as rubber, that provides a relatively great degree of friction between the fibers of the feed stream 9 and the second stage apron belts 18a and 18b.

The second stage apron belts 18a and 18b are preferably tensionally secured about sets 20a and 20b of two or more rollers. In this manner, when any one of the rollers 20a and 20b are rotated, the secoftd stage apron belts 18a and 18b are also rotated. The rotational power to the second stage apron belts 18a and 18b is provided by a stepper motor 54 (depicted in Fig. 2). The second stage apron belts 18a and 18b are driven in opposing rotational directions, such that the feed stream 9 which is received between them is drawn in between them and ejected out from between them on the other side.

The directions of rotation are selected to coincide with the directions of rotation of the first pinch rollers 16a and 16b. In other words, the second upper apron belt 20a and the first upper pinch roller 16a are rotating in a first direction, and the second lower apron belt 20b and the first lower pinch roller 16b are rotating in a second direction. The result of this configuration is that the feed stream 9 entering between the first pinch rollers 16a and 16b is urged in one direction along a path between the first pinch rollers 16a and 16b and the second stage apron belts 18a and 18b.

The speed at which the second stage apron belts 18a and 18b rotate is controlled by the speed control 42 (depicted in Fig. 2), and is independently variable depending on the draft ratio required. The rotational speed of the second stage apron belts 18a and 18b is greater than the speed at which the first pinch rollers 16a and 16b rotate, and the significance of this relationship is explained in greater detail below. In the preferred embodiment, the rotational speed of the second stage apron belts 18a and 18b is about 15 rpm.

Second platens 22a and 22b are disposed adjacent and on opposing sides of the second stage apron belts 18a and 18b. Because the second stage apron belts 18a and 18b are preferably constructed of an elastomeric material, the second platens 22a and 22b provide some rigidity and resistance to the second stage apron belts 18a and 18b along a distance between the rollers 20a and 20b on which the second stage apron belts 18a and 18b are mounted. This rigidity and resistance helps to enhance the friction between the second stage apron belts 18a and 18b and the feed stream 9 which is drawn between them. The platens 22a and 22b are preferably made of metal but could also be made of plastic, glass, or some other smooth, resilient material which has a low coefficient of friction so as to not cause excessive wear to the aprons.

The pressure between the second stage apron belts 18a and 18b and the fibers of the feed stream 9 is further enhanced by placing a pressure module 24a adjacent one or both of the second platens 22a and 22b. In Fig. 1, a pressure module 24a is depicted adjacent the second upper platen 22a, which makes the second upper platen 22a a pressure platen. The pressure module 24a may be a mechanical, hydraulic, or pneumatic device as described above, and is provided to further enhance and finely control the pressure exerted by tile second stage apron belts 18a and 18b on the fibers of the feed stream 9.

Unlike the first pinch rollers 16a and 16b, which are designed to allow no slip between the fibers of the feed stream 9, the components of the portion of the second stage 12 described above, being the second stage apron belts 18a and 18b, the rollers 20a and 20b, the platens 22a and 22b, and the pressure module 24a, are designed to allow a controlled degree of slip between the fibers of the feed stream 9. Thus, when the fibers are between the second stage apron belts 18a and 18b, it is intended that some of the fibers are advanced through the second stage apron belts 18a and 18b at a faster rate than others of the fibers in the feed stream 9. As fibers exit from between the second stage apron belts 18a and 18b at a greater rate than that at which they enter, due in part to the second stage apron belts 18a and 18b rotating faster than the first pinch rollers 16 and 16b, the feed stream 9 is thinned as it moves between the second stage apron belts 18a and 18b. In other words, the fibers within the feed stream 9 are partially, but not completely individualized as they move through the second stage 12. This is explained in greater detail below.

At the exit of the second stage apron belts 18a and 18b, the fibers of the feed stream 9 are received by second pinch rollers 16c and 16d. The second pinch rollers 16c and 16d are preferably configured in a manner very similar to the first pinch rollers 16a and 16b. In other words, one of the second pinch rollers 16c and 16d is preferably rubber and the other is preferably stainless steel. In alternate embodiments, both of the second pinch rollers 16c and 16d are either rubber or some other elaslomeric material, or stainless steel or some other hard material. The second pinch rollers 16c and 16d may be ribbed along their length to provide increased surfaces and edges for friction between the second pinch rollers 16c and 16d and the fibers of the feed stream 9 which pass between them.

Second adjustable pressure means 56b (depicted in Fig. 2) are used to adjust the pressure between the second pinch rollers 16c and 16d. The second adjustable pressure means 56b may be provided by one or more of several different mechanisms as explained above. As mentioned above for the first pinch rollers 16a and 16b, the materials from which the second pinch rollers 16c and 16d are formed are selected in part on their ability to firmly grasp and provide friction to the fibers of the feed stream 9. The adjustable pressure between the second pinch rollers 16c and 16d is also provided, in part, to enhance the ability of the second pinch rollers 16c and 16d to provide friction to the fibers of the feed stream 9. In this manner, the fibers of the feed stream 9 preferably do not slip between the second pinch rollers 16c and 16d.

Similar to that as previously described, the second pinch rollers 16c and 16d are rotated at the same speed and in opposing directions, so that the feed stream 9 placed between them is drawn between the second pinch rollers 16c and 16d and ejected out from between the second pinch rollers 16c and 16d on the other side. A stepper motor 54 (depicted in Fig. 2) provides the rotation between the second pinch rollers 16c and 16d, and the speed control 42 (depicted in Fig. 2), in communication with the stepper motor 54, independently controls the speed at which the second pinch rollers 16c and 16d rotate.

Preferably, the second pinch rollers 16c and 16d rotate at a speed that is greater than the speed at which the second stage apron belts 18a and 18b rotate. In the preferred embodiment, the second pinch rollers 16c and 16d rotate at a speed of about 30 rpm.

Thus, the fibers of the feed stream 9 are accelerated as they move through the first pinch rollers 16a and 16b, the second stage apron belts 18a and 18b, and the second pinch rollers 16c and 16d. This acceleration tends to thin out the feed stream 9 as briefly described above. To continue the explanation of how this is accomplished, as the fibers of the feed stream 9 pass through the first pinch rollers 16a and 16b, the trailing ends of each of the fibers are retainably held between the first pinch rollers 16a and 16b. The leading ends of the fibers, however, are tensionally drawn between the second stage apron belts 18a and 18b.

The first pinch rollers 16a and 16b, because they exert sufficient pressure on the fibers so that they are not released, prevent the fibers from being pulled through the second stage 12 at the faster rate at which the second stage apron belts 18a and 18b are rotating.

Thus, the second stage apron belts 18a and 18b are dragging past the fibers at a greater speed than that at which they are allowed to travel by the first pinch rollers 16a and 16b.

This is the importance of the pressure between the first pinch rollers 16a and 16b being sufficient to retain the fibers of the feed stream 9: so that the fibers are not dragged from between the first pinch rollers 16a and 16b until the end of the fiber is released from between the first pinch rollers 16a and 16b.

As the trailing end of an individual fiber is released from between the first pinch rollers 16a and 16b, the pressure exert on the fiber by the second stage apron belts 18a and 18b cause the fiber to accelerate to the speed of the second stage apron belts 18a and 18b.

Thus, the fiber so released are accelerated past, and drawn out from between the other fibers of the feed stream 9 that are still retained between the first pinch rollers 16a and 16b.

This action tends to thin and elongate the feed stream 9, which is a partial step toward the goal of individualizing the fibers. In other words, in the limit, as the feed stream 9 becomes longer and thinner, there ultimately comes a point at which the feed stream 9 contains only a single fiber at any point along its cross-section.

As mentioned above, the pressure between the second stage apron belts 18a and 18b provides a controlled degree of slip between the fibers of the feed stream 9. If the pressure between the second stage apron belts 18a and 18b is too great, it tends to break the fibers which have not yet been released from the first pinch rollers 16a and 16b. If the pressure between the second stage apron belts 18a and 18b is not great enough, then it is insufficient to overcome the friction between the fibers themselves and accelerate the fibers that have been released from the first pinch rollers 16a and 16b past the other fibers of the feed stream 9 that have not yet been released from the first pinch rollers 16a and 16b. Similarly, if the pressure between the first pinch rollers 16a and 16b is not great enough to prevent the fibers of the feed stream 9 from slipping out between them, then the fibers may be pulled out by the pressure exerted between the second stage apron belts 18a and 18b, and the fibers will not be thinned in a uniform manner.

There is a first gap 40 of between about one-half inches and about four and one-half inches between the first stage 10 and the second stage 12. The width of this gap 40 is selected based in part on the length of the fibers within the feed stream 9 that are processed through the individualizer 50. Preferably, the first gap 40 is set so that the distance between the first pinch rollers 16a and 16b and the second pinch rollers 16c and 16d is at least just greater than the length of the longest fibers in the feed stream 9. The reason for this is that both the first pinch rollers 16a and 16b and the second pinch rollers 16c and 16d exert sufficient pressure on the fibers such that the fibers are retainably held by both the first pinch rollers 16a and 16b and the second pinch rollers 16c and 16d.

Thus, if the first pinch rollers 16a and 16b and the second pinch rollers 16c and 16d were close enough together such that a liber were held by both the first pinch rollers 16a and 16b and the second pinch rollers 16c and 16d, the fiber would be broken or stretched by the individualizer S0. This is because the second pinch rollers 16c and 16d are rotating at a much greater rate of speed than are the first pinch rollers 16a and 16b. Thus, the second pinch rollers 16c and 16d would try to pull the fiber faster than the first pinch rollers 16a and 16b could release it. Because the friction between the first pinch rollers 16a and 16b and the second pinch rollers 16c and 16d is great enough so that fibers cannot slip from between them, the fiber would be broken. This would tend to invalidate any subsequent readings taken on the individualized fibers, such as length measurements.

In a manner similar to that in which leading fibers are drawn out ahead of trailing fibers as the fibers exit the first pinch rollers 16a and 16b and enter the second stage apron belts 18a and 18b, so also are leading fibers drawn out ahead of trailing fibers as the fibers enter the second pinch rollers 16c and 16d. Because the second pinch rollers 16c and 16d rotate at a faster speed than do the second stage apron belts 18a and 18b, the second pinch <BR> <BR> <BR> <BR> rollers 16c and 16d cause the fibers which are drawn into them to slip past other fibers at a rate of speed that is greater than the speed of the second stage apron belts 18a and 18b and the speed of the first pinch rollers 16a and 16b.

Thus, fibers within the feed stream 9 are moving at three different speeds in the area between the second stage apron belts 18a and 18b. The slowest moving fibers are those which are still retained between the first pinch rollers 16a and 16b and which are moving at the same speed as the first pinch rollers 16a and 16b. Accelerating past the slowest fibers are those which have been released from the first pinch rollers 16 and 16b and which are moving at the speed of the second stage apron belts 18a and 18b. Accelerating past both these slower two groups of fibers are those which have been drawn in by the second pinch rollers 16c and 16d and which are moving at the speed of the second pinch rollers 16c and 16d. Thus, these three speeds at which the fibers are moving tend to draft the feed stream 9, thinning it and elongating it, and providing a thinned stream 13 at the outlet of the second stage 12.

The rate of speed at which the second pinch rollers 16c and 16d are rotating is sufficient that fibers may tend to wrap around the second pinch rollers 16c and 16d, rather than being conducted along with the other fibers and being further processed. To reduce the occurrence of fibers wrapping around the second pinch rollers 16c and 16d in this manner, means are provided to urge the fibers of the thinned stream 13 along the proper path.

Several different methods may be used to accomplish this.

For example, blades may be placed along the second pinch rollers 16c and 16d at a position just rotationally after the point at which the fibers of the thinned stream 13 are released from the second pinch rollers 16c and 16d. In this manner, fibers which have a tendency to follow the direction of rotation and wrap around the second pinch rollers 16c and 16d encounter the blades and are redirected along the proper path.

Preferably, air knives 32a and 32b are used to keep the fibers within the thinned stream 13. The air knifes 32a and 32b are a series of air jets which are placed along the lengths of the second pinch rollers 16c and 16d and are directed at the output side of the second pinch rollers 16c and 16d. The air jets from the air knives 32a and 32b are directed in a substantially tangential manner to the second pinch rollers 16c and 16d. The air jets tend to blow the fibers of the thinned stream 13 off the edges of the second pinch rollers 16c and 16d, and into the proper path for further processing.

As the fibers of the thinned stream 13 exit the second pinch rollers 16c and 16d they are drawn in between third stage apron belts 18c and 18d. The process of thinning and elongating the thinned stream 13 then repeats in much the same manner as described above for the feed stream 9, which is thinned and elongated in and between the first stage 10 and the second stage 12. The third stage apron belts 18c and 18d are preferably an elastomeric material such as rubber, that provides a relatively great degree of friction between the fibers of the thinned stream 13 and the third stage apron belts 18c and 18d.

The third stage apron belts 18c and 18d are preferably tensionally secured about sets 20c and 20d of two or more rollers. In this manner, when any one of the rollers 20c and 20d are rotated, the third stage apron belts 18c and 18d are also rotated. The rotational power to the third stage apron belts 18c and 18d is provided by a stepper motor 54 (depicted in Fig. 2). The third stage apron belts 18c and 18d are driven in opposing rotational directions, such that the thinned stream 13 which is received between them is drawn in between them and ejected out from between them on the other side.

The directions of rotation are selected to coincide with the directions of rotation of the other rollers and belts mentioned above, such that the fibers are drawn along in the same direction throughout the individualizer 50. The speed at which the third stage apron belts 18c and 18d rotate is independently controlled by the speed control 42 (depicted in Fig. 2). The rotational speed of the third stage apron belts 18c and 18d is greater than the speed at which the second pinch rollers 16c and 16d rotate, the significance of which has been explained in great detail above, and which is briefly mentioned again below. In the preferred embodiment, the rotation speed of the third stage apron belts 18c and 18d is about 60 rpm.

Third platens 22c and 22d are disposed adjacent to and on opposing sides of the third stage apron belts 18c and 18d. Because the third stage apron belts 18c and 18d are preferably constructed of an elastomeric material, the third platens 22c and 22d provide some rigidity and resistance to the third stage apron belts 18c and 18d along a distance between the rollers 20c and 20d on which the third stage apron belts 18c and 18d are mounted. This rigidity and resistance helps to enhance the friction between the third stage apron belts 18c and 18d and the thinned stream 13 which is drawn between them.

The pressure between the third stage apron belts 18c and 18d and the fibers of the thinned stream 13 is further enhanced by placing pressure modules 24c and 24d adjacent each of the third platens 22c and 22d. In Fig. 1, a pressure module 24c is depicted adjacent the third upper platen 22c, which makes the third upper platen 22c a pressure platen, and a pressure module 24d is depicted adjacent the third lower platen 22d, which makes the third lower platen 22d a pressure platen. As previously mentioned, preferably only one of the third platens 22c and 22d is a pressure platen, and either the upper or the lower platen 22c and 22d may be selected and modified to be the pressure platen.

As described above, the pressure platens 22c and 22d are designed to allow a controlled degree of slip between the fibers of the thinned stream 13. Thus, when the fibers are between the third stage apron belts 18c and 18d, it is intended that some of the fibers advance through the third stage apron belts 18c and 18d at a faster rate than others of the fibers in the thinned stream 13. As fibers exit from between the third stage apron belts 18c and 18d at a greater rate than that at which they enter, the thinned stream 13 is further thinned as it moves between the third stage apron belts 18c and 18d. In other words, the fibers within the thinned stream 13 are individualized as they move through the third stage 14, in a manner as described in great detail above.

At the exit of the third stage apron belts 18c and 18d, the fibers of the thinned stream 13 are received by third pinch rollers 16e and 16f. The third pinch rollers 16e and 16f are preferably configured in a manner very similar to the first and second pinch rollers 16a, 16b, 16c, and 16d. In other words, one of the third pinch rollers 16e and 16f is preferably rubber and the other is preferably stainless steel. In alternate embodiments, the third pinch rollers 16e and 16f are configured as alternately described above.

Third adjustable pressure means 56c (depicted in Fig. 2) are used to adjust the pressure between the third pinch rollers 16e and 16f. The third adjustable pressure means 56c may be provided by one or more of several different mechanisms as explained above.

As mentioned above for the second pinch rollers 16c and 16d, the materials from which the third pinch rollers 16e and 16f are formed are selected in part on their ability to firmly grasp and provide friction to the fibers of the thinned stream 13. The adjustable pressure between the third pinch rollers 16e and 16f is also provided, in part, to enhance the ability of the third pinch rollers 16e and 16f to provide friction to the fibers of the thinned stream 13. In this manner, the fibers of the thinned stream 13 preferably do not slip between the third pinch rollers 16e and 16f.

Similar to that as previously described, the third pinch rollers 16e and 16f are rotated at the same speed and in opposing directions, so that the thinned stream 13 placed between them is drawn between the third pinch rollers 16e and 16f and ejected out from between the third pinch rollers 16e and 16f on the other side. A stepper motor 54 (depicted in Fig. 2) provides the rotation between the third pinch rollers 16e and 16f, and the speed control 42 (depicted in Fig. 2), in communication with the stepper motor 54, independently controls the speed at which the third pinch rollers 16e and 16f rotate. Preferably, the third pinch rollers 16e and 16f rotate at a speed that is greater than the speed at which the third stage apron belts 18c and 18d rotate. In the preferred embodiment, the third pinch rollers 16e and 16f rotate at a speed-of between about 300 rpm and about 400 rpm.

Thus, the fibers of the thinned stream 13 are accelerated as they move through the third pinch rollers 16e and 16f. This acceleration tends to thin out the thinned stream 13 as described above. To rehearse the explanation of how this is accomplished, as the fibers of the thinned stream 13 pass through the second pinch rollers 16c and 16d, the trailing ends of each of the fibers are retainably held between the second pinch rollers 16c and 16d. The leading ends of the fibers, however, are tensionally drawn between the third stage apron belts 18c and 18d.

The second pinch rollers 16c and 16d, because they exert sufficient pressure on the fibers so that they are not released, prevent the fibers from being pulled through the third stage at the faster rate at which the third stage apron belts 18c and 18d are rotating. Thus, the third stage apron belts 18c and 18d are dragging past the fibers at a greater speed than that at which they are allowed to travel by the second pinch rollers 16c and 16d.

As the trailing end of an individual fiber is released from between the second pinch rollers 16c and 16d, the pressure exerted on it by the third stage apron belts 18c and 18d cause the fiber to accelerate to the speed of the third stage apron belts 18c and 18d. Thus, the fiber so released accelerates past, and is drawn out from between the other fibers of the thinned stream 13 that are still retained between the second pinch rollers 16c and 16d. This action tends to thin and elongate the thinned stream 13, and completes the goal of individualizing the fibers.

As mentioned above, the pressure between the third stage apron belts 18c and 18d provides a controlled degree of slip between the fibers of the thinned stream 13. If the pressure between the third stage apron belts 18c and 18d is too great, it tends to break the fibers which have not yet been released from the second pinch rollers 16c and 16d. If the pressure between the third stage apron belts 18c and 18d is not great enough, then it is insufficient to accelerate the fibers that have been released from the second pinch rollers 16c and 16d past the other fibers of the thinned stream 13 that have not yet been released from the second pinch rollers 16c and 16d. Similarly, if the pressure between the second pinch rollers 16c and 16d is not great enough to prevent the fibers of the thinned stream 13 from slipping out between them, then the fibers may be pulled out by the pressure exerted between the third stage apron belts 18c and 18d, and the fibers will not be individualized in a uniform manner.

There is a second gap 38 of between about one-half inches and about six and one- half inches between the second stage 12 and the third stage 14. The width of this gap 38 is selected based in part on the length of the fibers within the thinned stream 13 that are processed through the individualizer 50. Preferably, the second gap 38 is set so that the distance between the second pinch rollers 16c and 16d and the third pinch rollers 16e and 16f is at least just greater than the length of the longest fibers in the thinned stream 13. As mentioned above, the reason for this is that both the second pinch rollers 16c and 16d and the third pinch rollers 16e and 16f exert sufficient pressure on the fibers that the fibers are retainably held by both the second pinch rollers 16c and 16d and the third pinch rollers 16e and 16f, and would break the fibers if they were held in each at the same time.

In a manner similar to that in which leading fibers are drawn out ahead of trailing fibers as the fibers exit the second pinch rollers 16c and 16d and enter the third stage apron belts 18c and 18d, so also are leading fibers drawn out ahead of trailing fibers as the fibers enter the third pinch rollers 16e and 16f. Because the third pinch rollers 16e and 16f rotate at a faster speed than do the third stage apron belts 18c and 18d, the third pinch rollers 16e and 16f cause the fibers which are drawn into them to slip past other fibers at a rate of speed that is greater than the speed of the third stage apron belts 18c and 18d and the speed of the second pinch rollers 16c and 16d.

Thus, fibers within the thinned stream 13 arc moving at three different speeds in the area between the third stage apron belts 18c and 18d. The slowest moving fibers are those which are still retained between the second pinch rollers 16c and 16d and which are moving at the same speed as the second pinch rollers 16c and 16d. Accelerating past the slowest fibers are those which have been released from the second pinch rollers 16c and 16d and which are moving at the speed of the third stage apron belts 18c and 18d. Accelerating past both these slower two groups of fibers are those which have been drawn in by the third pinch rollers 16c and 16f and which are moving at the speed of the third pinch rollers 16e and 16f. Thus, these three speeds at which the fibers are moving tend to further draft the thinned stream 13, producing individualized fibers 15 at the outlet of the second stage 12.

The rate of speed at which the second stage apron belts 18c and 18d are rotating is sufficient that fibers may tend to wrap around the second stage apron belts 18c and 18d, rather than being conducted along with the other fibers and being further processed. To reduce the occurrence of fibers wrapping around the second stage apron belts 18c and 18d in this manner, means are provided to urge the fibers of the thinned stream 13 along the proper path. As mentioned above, air knives 32c and 32d are preferably used to keep the fibers within the thinned stream 13.

The individualized fibers 15 are released one at a time from the third pinch rollers 16e and 16f and conducted along an air stream created at the entrance of a vacuum nozzle 26. Although the third pinch rollers 16e and 16f are also rotating at a speed sufficient that fibers 15 may tend to wrap around them, the draft created by the vacuum nozzle 26 is preferably great enough that the fibers 15 are drawn into the vacuum nozzle 26 and do not wrap around the third pinch rollers 16e and 16f. Thus, in the preferred embodiment, air knives are not required at the outlet of the third pinch rollers 16e and 16f. However, air knives could be placed at the outlet of the third pinch rollers 16e and 16f, and also at the outlet of any of the other rollers and belts mentioned above.

There is a third gap 36 of between about zero inches and about one-quarter inches between the third stage 14 and the vacuum nozzle 26. Preferably, this gap is set once for optimal performance of the apparatus, and then should not require further adjustment. The length of the vacuum nozzle 26 is preferably sufficient such that fibers 15 do not extend past the innermost part of the vacuum nozzle 26 prior to being release by the third pinch rollers 16e and 16f. In this manner, the several individualized fibers 15 that may be within the vacuum nozzle 26 at any given time tend to not tangle prior to being released. To further prevent the individualized fibers 15 from tangling, the airflow drawn into the vacuum nozzle 26 is preferably non-turbulent. Thus, the air flows into the vacuum nozzle 26 in a laminar manner, and the individualized fibers 15 are not entangled one with another by swirling air currents. The shape of the vacuum nozzle 26 and the speed of the air flow within it are selected based in part on providing the non-turbulent air flow. The speed of the air flow is preferably greater than the linear velocity at the circumference of the third pinch rollers 16e and 16f. The non-turbulent air stream within the vacuum nozzle 26 may also be thought of as a drafting stage, due to the non-linear velocity of the air stream as it is drawn through the vacuum nozzle and the design of the vacuum nozzle 26.

The vacuum for the nozzle 26 is received from a vacuum source 34 via line 28. The vacuum source 34 draws the individualized fibers 15 through an analyzer 30. The analyzer 30 preferably includes sensors, memory, buss lines, software, firmware, and other hardware required for detecting and analyzing physical properties of the individualized fibers 15 as they are received from the third stage 14. For example, the analyzer 13 may determine the color, moisture content, length, or tensile strength of the individualized fibers 15.

While the invention has been described in detail, it is apparent to persons skilled in the relevant art that the invention may be modified without departing from the spirit of the invention. Various changes of form, design or arrangement may be made to the invention without departing from the spirit and scope of the invention. Therefore, the above- mentioned description is to be considered exemplary, rather than limiting, and the true scope of the invention is that as defined in the following claims.