US3762144A

US3762144A - Apparatus for separating fibers from fibrous sliver

Info

Publication number: US3762144A
Application number: US00128901A
Authority: US
Inventors: S Didek; Z Svec
Original assignee: Vyzkumny Ustav Bavlnarsky AS
Current assignee: Vyzkumny Ustav Bavlnarsky AS
Priority date: 1970-03-27
Filing date: 1971-03-29
Publication date: 1973-10-02
Anticipated expiration: 1990-10-02
Also published as: CS152074B1; FR2083617A1; DE2113180B2; GB1350783A; JPS5415935B1; DE2113180A1; SU555181A1; FR2083617B1; DE2113180C3

Abstract

A rotary carding roller receives a fibrous sliver which moves from a supply device in a predetermined path towards the carding roller. A feed roller is located in this path and receives from the supply device fibrous sliver on its circumferential surface, to subsequently release the sliver to the carding roller. Contact means defines with the feed roller a nip zone upstream of the carding roller and operative for effecting contact of the fibrous sliver with the feed roller in a sense resulting in travel of the sliver on and with the circumferential surface from the nip zone to the carding roller.

Description

United States Patent Didk et a1. 1 1 Oct. 2, 1973 [54] APPARATUS FOR SEPARATING FIBERS 3,108,330 10/1963 Atkinson 19/105 X FROM FIBROUS SLIVER 3,115,683 12/1963 Reiterer 1 1 19/105 v v 3,335,558 8/1967 Doudlebsky et a1... 57/5895 1 1 lnvemorsl Stanisav Didek; Zdenek Svec, h of 3,360,918 1/1968 Doudlebsky et al... 19 105 x Usti nad Orlici, Czechoslovakia 3,411,187 11/1968 Groce et a1. 19/105 3,571,859 3/1971 Doudlebsky et al.. l9/l05 [73] AS51811: vulklmny Bavlnarsky, 3,626,681 12 1971 Naruse 57/5891 nacl Orlici, Czechoslovakia 22 Filed; Man 29 1971 Primary Examiner]ohn Petrakes AttorneyMichael S. Striker [21] Appl. No.: 128,901

[57] ABSTRACT [30] Foreign Application Priority Data A rotary carding roller receives a fibrous sliver which Mar. 27, 1970 Czechoslovakia 2032/70 moves from a pp y device in a predetermined p towards the carding roller. A feed roller is located in [52] US. Cl... 57/58.9l, 19/105, 57/5895 this path and receives from the supply device fibrous [51] Int. Cl D0lh 1/12 sliver on its circumferential surface, to q n ly 53 Field f Search. 57/50 5339-5895; release the sliver to the carding roller. Contact means 19/105 defines with the feed roller a nip zone upstream of the carding roller and operative for effecting contact of the [56] References Cit d fibrous sliver with the feed roller in a sense resulting in UNITED STATES PATENTS travel of the sliver on and with the circumferential sur- 2,912,720 11 1959 Vandergriff et a1. .1 19 105 x face from the mp Zone to the cardmg roller 3,439,488 4/1969 Bucil et a1 57/5895 18 Claims, 18 Drawing Figures PATENTEW 3.152.144

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SHEET 07 0F 11 i ATTORN EY PATENTEDIIEI 2191s saw us or 11 INQENTOR}; MIMI! non ATTO R N EY sum 10 or 11 INVENTOR5 81201:! 0am I BY ATTORN EY APPARATUS FOR SEPARATING FIBERS FROM FIBROUS SLIVER BACKGROUND OF THE INVENTION The present invention relates generally to fiber separating apparatus, and more particularly to an apparatus for separating fibers from fibrous formation such as.- sliver or the like.

In certain types of spinning machines, for instance so-called break-spinning machines which process fibers in so-called spinning chambers in form of a ribbon of fibers deposited on an internal collecting surface of the spinning chamber, it is necessary that the fibers be deposited on this collecting surface in form of a uniform fibrous ribbon which is continuous. The composition and quality of the thus deposited fibrous ribbon influence to a very considerable extent the quality of the resulting yarn which is spun in the rotary spinning chamber by twisting the fibrous ribbon and withdrawing it from the spinning chamber continuously. Furthermore, these characteristics also effect the rate of breakage, that is the rate at which severing of the ribbon or of the yarn being withdrawn occurs, and this breakage which results inthe frequent necessity for stopping the spinning processimpairs the quality of the final product.

While the composition and quality as well as uniformity of the fibrous ribbon are thus very important, it is clear that these characteristics in turn depend to a large extent upon the manner and the efficiency of actual separation of the fibers being fed to the spinning chamber, when the fibrous structure in form of which they are initially supplied to the spinning apparatus is separated into its fibers. For this purpose a fiber separating apparatus is provided. It is already known to have such apparatus which utilizes a rotary carding cylinder having a toothed circumferential surface to which fibrous sliver or structure is fed by a feeding roller, to be engaged by the teeth of the carding roller and separated into its constituent fibers. There is usually provided opposite the feed roller a pressure lip which clamps the sliver. Such pressure lip has an edge over which the sliver is bent and which is located close to the circumferential surface of the carding roller.

When sliver is engaged by the toothed surface of the carding roller, it is separated into its constituent individual fibers and then transported by the carding roller via an outlet channel extending tangentially to the circumference of the carding roller, into the spinning chamber. Once the separated fibers have entered the I outlet channel which is downstream ofjtheir engagement by the carding roller, they-are carried along the channel into the spinning chamber by an airstream resulting from a subatmospheric pressure in the rotary spinning chamber, and this in turn is causedby ventilating apertures provided in the wall of .the spinning chamher and through which at high rotary speed of the spinning chamber air is ejected centrifugally.

The known constructions have the disadvantage in that fibers are engaged by the surface of the carding roller closely adjacent to the clamping edge of the pressure lip. This means that engagement with the fibers takes place while they are yet under the influenceof the pressure exerted by the pressure lip so that quite frequently the fibers are broken or snapped. Those skilled in the art will realize the disadvantages of this, because the shorter the fibers are in the fibrous ribbon which is converted into a yarn, the less-will be the quality of the resulting yarn; conversely, the longer the fibers the better will be the resulting yarn.

Attempts have been made to overcome to some extent this disadvantage by spacing the feed roller and its pressure lip farther away from the surface of the carding roller. However, this still does not overcome all of the drawbacks. Firstly such an arrangement is not suitable for processing fibrous structures having fibers of various staple lengths because the distance between the nip area, that is the area where the fibrous structure is clamped between the pressure lip and the feed roller, and the bite area where it is engaged by the toothed surface of the carding roller, remains constant. 0n the other hand, the increased distance thus obtained has heretofore had to be determined with regard to an average staple length and the drawbacks of this are clearly evident when it is considered that a sliver of fibrous material not only contains fibers of average length but also those which are shorter or longer than the average length. The longer fibers are clearly engaged more strongly by the toothed surface of the carding roller and will still be broken and shortened with this arrangement. Shorter fibers, however, after leaving the feed roller nip are carried along to engagement with the surface of the carding roller along with the longer fibers; due to inter-fibrous friction the longer fibers are at this time already exposed to the pulling action of the toothed surface of the carding roller whereas the shorter fibers so-called floating fibers are carried along without any positive feed. The result is that on the one hand uneven fiber separation takes place and, on the other hand, fiber tufts are carded or combed out which will form an irregular ribbon on the fiber collecting surface of the spinning chamber. This, in turn, results in a low-grade yarn of uneven structure. In fact, because not all of the fibers are duly aligned, with many of them being creased, crimped, or bent, the formation of such undesirable fiber tufts is even facilitated under these circumstances.

SUMMARY OF THE INVENTION It is, accordingly, an object of the present invention to overcome the above-mentioned disadvantages.

It particularly is an object of the present invention to provide an improved apparatus for separating fibers from fibrous sliver which is not possessed of these disadvantages.

In pursuance of the above objects, and others which will become apparent hereafter, one feature of the invention resides in an apparatus for separating fibers from fibrous sliver, in a combination which briefly stated comprises a rotary carding roller and a supply device supplying fibrous sliver for movement in a predetermined path towards the carding roller. A rotatable feed roller is located in this path and has a circumferential surface, being adapted to receive fibrous sliver from the supply device and to release such sliver to the carding roller. Further there is provided contact means which defines with the feed roller a nip zone upstream of the carding roller, serving for effecting contact of the fibrous sliver with the feed roller in a sense which results in travel of the sliver on and with the circumferential surface from the nip zone to the carding roller.

The contact means utilizes a pressure element which is preferably arranged opposite the circumference of the feed roller and adjustable along a circular path concentric with the axis of the feed roller. This makes it possible to permit an adjustment in the length of the path on which the sliver will travel on and with the surface of the feed roller before it is engaged by the carding roller. An additional pressure element may also be provided, similarly being adjustable in a circular path concentric to the axis of the feed roller, and providing on the surface of the feed roller a fiber directing zone for guiding the fibrous sliver on the feeding surface of the feed roller, such zone being followed by a free encircling zone within which the fibrous sliver passes along the circumference of the feeding surface of the feed roller but freely rather than being engated therewith, before it enters engagement with the carding roller.

The pressure elements can only be configurated as spring-loaded pressure rollers or segments which can be variously profiled. The manner of their cooperation with the feeding surface of the feed roller, as well as their support arrangements, may vary.

The novel features which are considered as characteristic for the invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation, together with additional objects and advantages thereof will be best understood from the following description of specific embodiments when read in connection with the accompanying drawing.

BRIEF DESCRIPTION OF THE DRAWING FIG. I is a somewhat diagrammatic elevational section of an apparatus embodying the present invention;

FIG. 2 is a diagrammatic detail view of the apparatus shown in FIG. 1, in an enlarged scale and in a sectional elevation;

FIG. 3 is a view similar to FIG. 2 but illustrating a further embodiment of the invention;

FIG. 4 is a fragmentary view analogous to FIG. 3 illustrating yet an additional embodiment of the invention;

FIG. 5 is a view similar to FIG. 4 but illustrating a further embodiment of the invention;

FIG. 6 is a diagrammatic sectional detail view, onan enlarged scale, taken on line AA of FIG. 1;

FIG. 7 is a view similar to FIG. 6 but illustrating a further embodiment;

FIG. 8 is a view similar to FIG. 4 illustrating another embodiment of the invention;

FIG. 9 is a view similar to FIG. 8 illustrating a modified embodiment of the invention;

FIG. 10 is a view similar to FIG. 9 showing yet another embodiment of the invention;

FIG. II is a section taken on line A-A of FIG. 8;

FIG. 12 is a view similar to FIG. 11 showing a modified embodiment of the invention;

FIG. H3 is a view resembling FIG. 11 but showing still a further embodiment of the invention;

FIG. 14 is a view similar to FIG. 9 showing another embodiment of the invention;

FIG. 15 is still an additional view similar to FIG. 14 but illustrating a modified embodiment;

FIG. 16 is a view taken on line A-A of FIG. 14;

FIG. 17 is a view similar to FIG. 16 illustrating a modification; and

FIG. I8 is a view similar to FIG. 17 illustrating still a further embodiment.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Discussing now the drawing in detail, and firstly FIG. 1 thereof, it will be seen that we have shown our novel apparatus incorporated in a break-spinning machine having a rotary spinning chamber 1 of well known construction. Our fiber separating apparatus is mounted in the housing 2 of the spinning machine and essentially comprises a rotary carding cylinder 3 having a toothed circumferential surface in known manner. A feed roller 4 and a cooperating pressure roller 5 are provided. A sliver or similar fibrous formation to be separated into its constituent fibers is supplied to the nip between the feed foller 4 and the pressure roller 5 by means of a condenser 7 of known construction. Once the fibers are separated and supplied on the inner circumferential fiber collecting surface 10 of the spinning chamber which rotates about the indicated upright axis, they slide to the fiber-collecting ribbon-forming surface 11 from where the ribbon is withdrawn in twisted condition as a yarn in the direction of the arrow. The yarn is indicated with reference numeral 8 and is being withdrawn by a pair of cooperating withdrawal rollers 9 which supply it to a non-illustrated take-up device.

In conventional manner the spinning chamber 1 forms subatmospheric pressure in its interior when it rotates, in that air is ejected under the influence of cen trifugal force through the apertures shown in the circumferential wall of the spinning chamber 1. This serves to aspirate the separated fibers into the interior of the spinning chamber.

The carding roller 3 is keyed or otherwise nonrotatably mounted on a rotary shaft 12 for rotation with the latter. Its outer circumferential surface is provided with wires, pegs, teeth or the like which are identified with reference numeral 13 and which engage the sliver and separate it into its constituent fibers. Roller 3 is mounted in a chamber 14 of housing 2, and a channel 15 extending tangentially to the circumference of the roller 3 communicates with the chamber 14 as well as .with the interior of the rotary spinning chamber 1, as

' illustrated. A drive for rotating the shaft 12 has not been shown; it is conventional and may be in form of the main drive belt of the spinning machine.

The feed roller 4 and the pressure roller 5, together with the condenser 7 if such a device is provided, primarily constitute the so-called feeding mechanism.

This is located in a chamber 16 also provided in the housing 2 and communicating with the chamber 14 via a a channel 17. Feed roller 4 is mounted on a shaft 18 which is positively driven in rotation and pressure roller 5 is either mounted for idling movement on a pin 19 which is slidably mounted in slots 20 in arms 21 which are angularly adjustable about the axis of shaft 18 and can be arrested in a desired position by non-illustrated conventional means. Alternately, the feed roller 5 could also be driven by known means so as to rotate either in clockwise or in counterclockwise sense.

Pressure roller 5 is resiliently biased towards the feed roller 4 by biasing means, here illustrated in form of springs 22 located in the respective slots 20 and adjustable by means of screw 23 to exert more or less pressure. A bracket 24 supporting the stationary condenser 7 may be provided on the arms 21.

As the fibrous sliver passes through the nip between the pressure roller 5 and the feed roller 4, a resilient pressure is exerted upon it and the location at which such pressure is exerted upon it and the location at which such pressure is exerted influences the length of the path or of the distance over which the sliver will be in engagement and move along with the surface of the feed roller 4 before it is released therefrom to the carding roller 3. As pointed out already, this influences to a considerable extent the quality of separation obtained where the sliver is separated into its constituent fibers. In order to make it possible to change the position of the nip, that is the zone in which pressure is exerted on the sliver between the roller 5 and the roller 4, and to be able to extend to a maximum the length of the path over which the sliver encircles the surface of the feed roller 4, the present invention has been provided.

FIG. 2 shows the apparatus of FIG. 1, but on an enlarged scale. As shown there is provided a cylindrical baffle plate on the arms 21 and serves for preventing the feed roller 4 and the sliver 6 thereon from becoming soiled. In FIGS. 1 and 2 the contact point of the carding cylinder 3 with the fibrous sliver is generally designated with A, and the length of the path over which the sliver will encircle the circumference of the feed roller 4 is generally designated with reference character B. While the area A is non-variable, the length B can be varied in accordance with the present invention, by displacing the nip between the feed roller 4 and the pressure roller 5 where the sliver 6 is engaged. In FIGS. 1 and 2 this is accomplished by changing the position of the pressure roller 5 in that arms 21 are turned about the shaft 18. The distance of the nip between feed roller 4 and pressure roller 5 from the area A, that is substantially the length B, is adjusted in dependence upon the staple fiber length of the fibers in the fibrous material which is to be carded. As seen in FIGS. I and 2, the length B is much shorter when the feed mechanism is shown in FIG. 1 than the length B when the feed mechanism is in the position shown in FIG. 2. To some extent the fiber separation by the carding cylinder 3 can be influenced by the relative directions of rotation of the carding cylinder 3 and the feed roller 4. It will be seen that in FIGS. 1 and 2 the

rollers

3 and 4 rotate in opposite direction. Thus, sliver 6 is supplied to the area A along a free unobstructed path.

In the embodiment of FIG. 3 the

rollers

3 and 4 rotate in identical direction, by contrast to the FIGS. 1 and 2 embodiment. This means that sliver 6 is ad vanced from the nip between feed roller 4 and pressure roller 5 to engagement with the area 4 of the carding cylinder over a lip 26 which is provided in that part of "(I16 housing 2 where sliver 6 leaves contact with the feed roller 4.

As shown in FIG. 4 the pressure means which defines the nip with the feed roller 4 need not always be in form of a roller, such as the roller 5. In FIG. 4 the pressure element which engages the feed roller 4 and defines the aforementioned nip therewith is in form of a concave pressure segment 27 engaging a portion of the feed roller 4 circumference on a mating curved surface.

In the embodiment of FIG. 5 the pressure element is constituted by a convex pressure segment 28 which engages the feed roller 4 along a line to form the nip therewith.

In the FIG. 4 embodiment the pressure segment 27 of concave configuration is mounted on a pin 29 which is received in slots 30. These are formed in oscillating arms 31 which are adapted to oscillate about a pin 32 the position of which can be adjusted in a circular guideway 33 concentric with the circumference of the feed roller 4. It is evident that by displacing the pin 32 the angular position of the nip on the feed roller circumference can similarly be displaced. A bracket 24 holding the condenser 7 is also provided on the pin 32, as well as a helical spring 34 which resiliently urges the arms 31 and therefore the pressure segment 27 against the circumference of the feed roller 4.

As shown in FIG. 6 the feed roller 4 may be without flanges, or it may be provided with end flanges 46 as shown in FIG. 7. Generally speaking, the provision of flanges is preferable because this provides for a better guidance of the sliver. The operating width of the feeding surface 35 on the feed roller 4 which feeding surface incidentally can be smooth or fluted, knurled or the like corresponds substantially to that of the circumferential surface on the carding roller 3 as well as of the

respective pressure element

5, 27 or 28.

In the embodiments discussed thus far, namely of FIGS. 1-7, sliver 6 passing over the circumference of the feed roller 4 is pressed against the surface 35 of the latter only in a single nip area which can be adjusted in order to vary the length B of the path over which the sliver will encircle the feed roller 4. In the embodiments to follow, namely of FIGS. 8-18, the manner in which the sliver 6 is guided on the surface 35 of the feed roller 4, is improved by adding what we choose to call a fiber directing zone C. This is defined at one side by the aforementioned nip area of the pressure element, such as the roller 5 or the

segments

27 or 28; at the other side it is defined by an element which produces what we also choose to call a control nip. It should be understood that the sliver 6 will continue to encircle the surface 35 of the feed roller 4 even after it has left the control nip which is produced in accordance with the embodiments to be described.

In FIG. 8 such components as are identical with components of the preceding embodiments, are identified with the same reference numeral. The control nip for the fibrous sliver is obtained by providing a control pressure roller 36 which can be supported and resiliently biased against the surface 35 of the roller 4 in the same manner in which the pressure roller 5 of FIGS. 1 and 2 is biased in that sense. The roller 36 is mounted on a pin 16 supported in slots 20 which in turn are formed in arms 21. These arms are mounted so as to be displaceable about shaft 18 which also mounts the feed roller 4; and springs 22 received in the slots 20 and being adjustable by means of screws 23, provide resilient pressure.

The fiber directing zone C is provide between the nip area defined by the feed roller 4 and the pressure roller 5, and the control nip area defined by the pressure roller 4 and the control pressure roller 36. The zone C is followed by a zone B in which the fibrous sliver loosely encircles the surface 35 of the feed roller 4 prior to reaching the contact area A where it is engaged by the carding roller 3. In this manner the sliver 6 can be controlled over an enlarged portion of its path so that the supply of sliver can be accommodated to a greater extent to the conditions of the material to be processed, and this in turn advantageously affects the quality of the entire spinning process and the resulting product.

In FIG. 9 we have illustrated an embodiment in which the pressure roller 5 and the control pressure roller 36 are supported by their respective pins 19 in slots 30 of arms 31 swingably about

pins

32 and 32. These pins are displaceable and arrestable in requisite position in a curvilinear guideway 33 which is concentric with the axis of feed roller 4. As previously discussed, the pressure exerted by arms 31 and therefore by th rollers and 36, respectively, is obtained by helical springs 34 which make the rollers bear upon the feed roller 4. The bracket 24 again supports the condenser 7, but here is mounted on a pin 32" so that it can be displaced along the curvilinear guideway 33 in the same manner as the pins 32 and 32'.

In FIG. we have shown an embodiment in which pressure roller 5 is arranged in the same manner as discussed before in FIGS. 1 and 2, whereas the control pressure roller 36 is idle on a pin 37 mounted in double armed levers 38 which are swingable about a journal 39 secured in housing 2. A spring 46 is received in a recess 41 also provided in the housing 2 and forces the control pressure roller 36 towards the surface of the feed roller 4. Unlike the preceding embodiment, the embodiment of FIG. 10 does not provide for adjusting the position of the control pressure roller 36 with reference to the surface of the feed roller 4. The position of the pressure roller 5 and consequently the range of the fiber directing zone C, however, can be adjusted as previously described.

FIGS. 11, 12 and 13 show how the control pressure roller 13 can be differently configurated. In FIG. 11 the roller 36 is simply of cylindrical configuration, whereas in FIG. 12 it is provided at its opposite axial ends with radial flanges 50. In FIG. 11 maximum control pressure is obtained, whereas in FIG. 12 a much smaller and in fact minimal control pressure can be utilized because of the more definite guidance of the type of sliver between the flanges 50. In the embodiment of FIG. 13 the control pressure roller 36 is provided with a shoulder 51 at each axial end so that the roller 36 can enter between mating flanges 46 of the feed roller 4. In this embodiment maximum control pressure can also be exerted and the supply rate of fibrous sliver is identical in all three embodiments.

FIGS. 14 and 15 show that other types of pressure elements can be utilized in place of the heretofore described control pressure rollers, for obtaining the control pressure defining the end of the fiber directing zone C. FIG. 14 shows the pressure roller 5 and the condenser 7 to be arranged so that they can positionly be adjusted in the curvilinear guideway 33 in the manner described with reference to FIG. 9. In this embodiment a control pressure segment 42 is provided which exerts the control pressure and is secured to an extremity of a rod member 43 which is mounted so that it can reciprocate in a bore 4% provided in a block 2'. A spring 45 bears upon the rod 43 to urge the latter and thereby the segment 42, resiliently towards the surface of the feed roller 4.

In FIG. 15 the control pressure segment 45 is of convex type, as opposed to the concave configuration of the control pressure segment 42 of FIG. 14. Thus,-in FIG. 15 the segment 45 engagesthe surface 45 of the feed roller 4 along a linearly configurated nip.

FIGS. 16, 17 and 18 finally disclose some modifications of the contact area between the control pressure segment 82 and the feed roller 4. In FIG. 16 the control pressure segment 42 is provided with a bare or smooth surface and engages the outer circumference of the flanges 46 of the feed roller 4 only at its extremities. In FIG. 17, on the other hand, the control pressure segment 42' is provided with flanges 47 the outer surfaces of which engage the outer surfaces of the flanges 46 on the feed roller 4. Thus, the control pressure nip obtained on the sliver 6 between the segment 42 and the surface 35 of the feed roller 4 in this embodiment is less or looser than with the embodiment in FIG. 16.

Finally, the most intensive control pressure engagement or nip between the segment 42" and the feeding surface 35 of the feed roller 4 is attained with the embodiment in FIG. 18. Here the segment 42' is provided with a shoulder 48 adapted to enter between the flanges 46 of the feed roller 4 so that the segment 42' can move closer to the active or feeding surface 35 of the roller 4 and thus reduce the thickness of the nip which it defines with the same.

In operation of the apparatus according to the present invention the feed roller 4 together with the pressure element 5 (embodiment of FIGS. 1 and 2, for instance) supplies sliver 6 of fibrous material to the area A where it is engaged by the carding cylinder 3. The sliver 6 is supplied from the nip between the feed roller 4 and the pressure element 5 and moves on the feeding surface 35 of the feed roller 4. Sliver 6 either loosely encircles the surface 35 and forms the encircling zone B, or by means of the control pressure element 36 is may additionally have the so-called fiber directing zone C in which the sliver is exposed first to the pressure nip and then to the control pressure nip followed by the short encircling zone B Because the control pressure nip engages the fibers in sliver 6 subsequent to their engagement in the pressure nip, the so-called floating fibers mentioned earlier and which are shorter than the average stable lengthare exposed to a higher interfibrous friction whereby the carding cylinder 3 is prevented from withdrawing a randomly accumulated fiber tuft all at once and is instead compelled to withdraw the fibers successively.

Fibers 52 having been carded out of the sliver 6 are passed through the outlet channel 15 to the surface 10 of the spinning chamber 1 where they are finally deposited by sliding over the surface 10 on the collecting surface 11. On this they are formed into a ribbon which is twisted to assume the form of a yarn 8 which is drawn off by means of the withdrawal rollers 9.

It will be clear that the embodiments according to the present invention make it possible to accommodate the fiber feeding mechanism to specific conditions of processing a sliver or similar structure 6 of fibrous material, in order to attain an optimum quality of the final yarn product.

It is thus possible by using the simple means illustrated by the exemplary embodiments of FIGS. 1-7, to vary the distance of the nip between the feed roller 4 and the

respective pressure elements

5, 27 or 28, respectively, from the area A of engagement with the carding cylinder 3; this, in turn, varies the length of the path or zone D in which the sliver loosely encircles the surface of the feed roller 4.

Also, the linear contact of the pressure element 5 in FIGS. 1-3 and 5-7 can be replaced by the area contact afforded by the pressure element 27 in FIG. 4. Apart from the pressure force control afforded by the

springs

22 and 34, the force in the nip between the feed roller 4 and the

pressure element

5 and 27, respectively, can be regulated by varying the cross-sectional configuration of the pressure element and 27 as shown in FIGS. 6 and 7.

If loose encircling of the surface of the feed roller 4 by the sliver is not adequate, particularly if long staple or wool-type yarns are to be processed, it may be advisable to use the additional control pressure element which is for instance disclosed in form of the roller 36 in FIGS. 8-13, or of the segment 42 disclosed in FIGS. 14 and 16-18. Again, it is also possible to use the segment 49 of FIG. 15. The roller 36 and the segment 49 engage the surface 35 of the feed roller 4 in linear contact whereas utilization of the segment 42 achieves an area contact.

In such conditions where the additional

control pressure elements

36, 42 and 49 are utilized, the fiber directing zone C is obtained which is defined between their respective control nip with the feeding surface 35 of the feed roller 4 and the pressure nip exerted by the feeding surface 35 of the pressure roller 4 and the pressure element 5. The existence of this fiber directing zone C improves the control over the guidance of the sliver 6 on the feeding surface 35 of the feed roller 4 and the zone C is followed by the shorter zone B, in which the sliver loosely encircles the surface 35 of roller 4 before it reaches the area A where it is engaged by the carding roller 3.

However, it must be understood that under no circumstances the additional control nip may assume the function of the ordinary nip in which the fibers are clamped. Thus the rate of contact afforded by the control nip can be controlled not only by regulating the force of the pressure springs 22 or 45 but also by varying the profile of the pressure element 36 as shown in FIGS. 11-13, or 42 as shown in FIGS. 16-18.

The length of the fiber directing zone C and the length of the zone B can be controlled by displacing both the pressure element 5 and the additional control pressure element 36 along the circumference of the feed roller 4 as shown in FIGS. 8 and 9, and the length of the zone C can also be varied by changing the position of the pressure element 5 as shown in FIGS. l0, l4 and in the latter case the length of the encircling zone B remains constant.

It must be understood that even with arrangements equipped with additional control pressure elements such as the

elements

36, 42 and 49, any of these elements can be simply disengaged in which case the sliver 6 will loosely encircle the surface 35 of the feed roller 4 along a longitudinally controllable zone. The width of the

control pressure elements

36, 42 and 49, respectively, as well as that of the

pressure elements

5, 27 and 28, respectively, corresponds to the sum of the width of the feeding surface 35 and of the flanges 46 of the feed roller 4.

It will be understood that each of the elements described above, or two or more together, may also find a useful application in other types of constructions differing from the types described above.

While the invention has been illustrated and described as embodied in an apparatus for separating fibers from fibrous sliver, it is not intended to be limited to the details shown, since various modifications and structural changes may be made without departing in any way from the spirit of the present invention.

Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can by applying current knowledge readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention and, therefore, such adaptations should and are intended to be comprehended within the meaning and range of equivalence of the following claims.

What is claimed as new and desired to be protected by Letters Patent is set forth in the appended 1. In an apparatus for separating fibers from fibrous sliver, in combination, a rotary carding roller; a supply device supplying fibrous sliver for movement in a predetermined path towards said carding roller; contact means proximal to said path upstream of said carding roller; a rotatable feed roller in said path adjacent said contact means and defining therewith a nip zone arranged to receive fibrous sliver from said supply device, said feed roller having a circumferential surface an arcuate portion of which extends from said nip zone downstream along said path to the vicinity of said carding roller and defines a sliver control zone in which the sliver travels in engagement with said circumferential surface from said nip zone to the vicinity of said carding roller and biasing means permanently urging said contact means towards said circumferential surface so as to define said nip zone therewith.

2. In an apparatus as defined in claim 1, wherein said circumferential surface contacts said sliver in said nip zone at one circumferential location of said feed roller, and releases the sliver in said vicinity of said carding roller at an other circumferentially spaced location; and further comprising displacing means operatively associated with said contact means for displacing the same relative to said feed roller in a sense shifting said nip zone circumferentially thereof so as to vary the circumferential spacing between said locations.

3. In an apparatus as defined in claim 2, said displacing means comprising arms mounting said contact means for displacement circumferentially of said feed roller.

4. In an apparatus as defined in claim 2, said circumferential surface of said feed roller having an axial length corresponding to that of said carding roller and of said contact means; and further comprising radially projecting flanges at opposite axial ends of said circumferential surface of said feed roller.

5. In an apparatus as defined in claim 2, said contact means being a contact roller mounted for rotation about an axis parallelling that of said feed roller.

6. In an apparatus as defined in claim 2, said contact means comprising a segment-shaped contact member.

7. In an apparatus as defined in claim 2; and further comprising an additional contact element resiliently biased towards said circumferential surface intermediate said nip zone and said carding roller.

8. In an apparatus for separating fibers from fibrous sliver, in combination, a rotary carding roller; a supply device supplying fibrous sliver for movement in a predetermined path towards said carding roller; contact means proximal to said path upstream of said carding roller; a rotatable feed roller in said path adjacent said contact means and defining therewith a nip zone arranged to receive fibrous sliver from said supply device, said feed roller having an axis of rotation and a circumferential surface an arcuate portion of which extends from said nip zone downstream along said path to the vicinity of said carding roller and defines a sliver control zone in which the sliver travels in engagement with said circumferential surface from said nip zone to the vicinity of said carding roller, said circumferential surface contacting said sliver in said nip zone at one circumferential location of said feed roller and releasing the sliver in the vicinity of said carding roller at an other circumferentially spaced location; and displacing means comprising arms carrying said contact means and being mounted for movement in a sense effecting displacement of said contact means about said axis so as to shift said nip zone circumferentially of said feed roller and vary the circumferential spacing between said locations.

9. In an apparatus for separating fibers from fibrous sliver, in combination, a rotary carding roller; a supply device supplying fibrous sliver for movement in a predetermined path towards said carding roller; contact means proximal to said path upstream of said carding roller; a rotatable feed roller in said path adjacent said contact means and defining therewith a nip zone arranged to receive fibrous sliver from said supply device, said feed roller having an axis of rotation and a circumferential surface an arcuate portion of which extends from said nip zone downstream along said path to the vicinity of said carding roller and defines a sliver control zone in which the sliver travels in engagement with said circumferential surface from said nip zone to the vicinity of said carding roller, said circumferential surface contacting said sliver in said nip zone at one circumferential location of said feed roller and releasing the sliver in the vicinity of said carding roller at an other circumferentially spaced location; and displacing means comprising arms carrying said contact means and being displaceably mounted in a curvilinear guideway extending circumferentially of said axis so as to shift said nip zone circumferentially of said feed roller and vary the circumferential spacing between said locations.

10. In an apparatus for separating fibers from fibrous sliver, in combination, a rotary carding roller; a supply device supplying fibrous sliver for movement in a predetermined path towards said carding roller; contact means proximal to said path upstream of said carding roller; a rotatable feed roller in said path adjacent said contact means and defining therewith a nip zone arranged to receive fibrous sliver from said supply device, said feed roller having an axis of rotation and a circumferential surface an arcuate portion of which extends from said nip zone downstream along said path to the vicinity of said carding roller and defines a sliver control zone in which the sliver travels in engagement with said circumferential surface from said nip zone to the vicinity of said carding roller, said circumferential surface contacting said sliver in said nip zone at one circumferential location of said feed roller and releasing the sliver in the vicinity of said carding roller at an other circumferentially spaced location; displacing means for effecting displacement of said contact means so as to shift said nip zone circumferentially of said feed roller and vary the circumferential spacing between said locations, and radially projecting flanges at opposite axial ends of said circumferential surface; and a contact roller element resiliently biased towards said circumferential surface intermediate said nip zone and said carding roller and having an axial length corresponding at least substantially to the combined axial lengths of said circumferential surface and said flanges.

11. In an apparatus for separating fibers from fibrous sliver, in combination, a rotary carding roller; a supply device supplying fibrous sliver for movement in a predetermined path towards said carding roller; contact means proximal to said path upstream of said carding roller; a rotatable feed roller in said path adjacent said contact means and defining therewith a nip zone arranged to receive fibrous sliver from said supply device, said feed roller having an axis of rotation and a circumferential surface an arcuate portion of which extends from said nip zone downstream along said path to the vicinity of said carding roller and defines a sliver control zone in which the sliver travels in engagement with said circumferential surface from said nip zone to the vicinity of said carding roller, said circumferential surface contacting said sliver in said nip zone at one circumferential location of said feed roller and releasing the sliver in the vicinity of said carding roller at an other circumferentially spaced location; and displacing means comprising arms carrying said contact means and being mounted for movement in a sense effecting displacement of said contact means about said axis so as to shift said nip zone circumferentially of said feed roller and vary the circumferential spacing between said locations; a contact roller element resiliently biased towards said circumferential surface intermediate said nip zone and said carding roller; mounting arm means mounting said contact roller element for free turning movement about an axis of rotation paralleling that of said feed roller; biasing means permanently biasing said contact roller elements towards said circumferential surface; and mounting means mounting said mounting arm means for movement circumferentially of said feed roller. 7

12. In an apparatus as defined in claim 11, said mounting arm means being a double-armed lever mounted for displacement about a stationary journal; and said biasing means comprising a spring acting upon said lever in a sense tending to displace the same towards said circumferential surface about said journal.

13. In an apparatus as defined in claim 11, said mounting means comprising a curvilinear guideway extending circumferentially of said feed roller, pin means on said mounting arms slidably received in said guideway, anda spring urging said mounting arms with said roller element toward said circumferential surface.

14. In an apparatus as defined in claim 11, said contact roller element having at opposite axial ends thereof radially projecting flanges; and wherein said feed roller has additional flanges at its opposite axial ends and in engagement with said flanges of said roller element.

15. In an apparatus as defined in claim 11, said feed roller having radial flanges at its opposite axial ends; and wherein said contact roller element has axially spaced shoulders which are moved between said flanges of said feed roller.

16. In an apparatus for separating fibers from fibrous sliver, in combination, a rotary carding roller; a supply device supplying fibrous sliver for movement in a predetermined path towards said carding roller; contact means proximal to said path upstream of said carding roller; a rotatable feed roller in said path adjacent said contact means and defining therewith a nip zone arranged to receive fibrous sliver from said supply device, said feed roller having an axis of rotation and a circumferential surface an arcuate portion of which extends from said nip zone downstream along said path to the vicinity of said carding roller and defines a sliver control zone in which the sliver travels in engagement with said circumferential surface from said nip zone to the vicinity of said carding roller, said circumferential surface contacting said sliver in said nip zone at one circumferential location of said feed roller and releasing the sliver in the vicinity of said carding roller at an other circumferentially spaced location; and displacing means comprising arms carrying said contact means and being mounted for movement in a sense effecting displacement of said contact means about said axis so as to shift said nip zone circumferentially of said feed roller and vary the circumferential spacing between said locations; an additional segment-shaped contact element having a projection slidably received in a recess of said support proximal to said feed roller; and biasing means biasing said segment-shaped element toroller having radial flanges at its opposite axial ends','

and wherein said segment-shaped element has shoulders located intermediate and each cooperating with one of said radial flanges of said feed roller.

Claims

1. In an apparatus for separating fibers from fibrous sliver, in combination, a rotary carding roller; a supply device supplying fibrous sliver for movement in a predetermined path towards said carding roller; contact means proximal to said path upstream of said carding roller; a rotatable feed roller in said path adjacent said contact means and defining therewith a nip zone arranged to receive fibrous sliver from said supply device, said feed roller having a circumferential surface an arcuate portion of which extends from said nip zone downstream along said path to the vicinity of said carding roller and defines a sliver control zone in which the sliver travels in engagement with said circumferential surface from said nip zone to the vicinity of said carding roller and biasing means permanently urging said contact means towards said circumferential surface so as to define said nip zone therewith.

11. In an apparatus for separating fibers from fibrous slivEr, in combination, a rotary carding roller; a supply device supplying fibrous sliver for movement in a predetermined path towards said carding roller; contact means proximal to said path upstream of said carding roller; a rotatable feed roller in said path adjacent said contact means and defining therewith a nip zone arranged to receive fibrous sliver from said supply device, said feed roller having an axis of rotation and a circumferential surface an arcuate portion of which extends from said nip zone downstream along said path to the vicinity of said carding roller and defines a sliver control zone in which the sliver travels in engagement with said circumferential surface from said nip zone to the vicinity of said carding roller, said circumferential surface contacting said sliver in said nip zone at one circumferential location of said feed roller and releasing the sliver in the vicinity of said carding roller at an other circumferentially spaced location; and displacing means comprising arms carrying said contact means and being mounted for movement in a sense effecting displacement of said contact means about said axis so as to shift said nip zone circumferentially of said feed roller and vary the circumferential spacing between said locations; a contact roller element resiliently biased towards said circumferential surface intermediate said nip zone and said carding roller; mounting arm means mounting said contact roller element for free turning movement about an axis of rotation paralleling that of said feed roller; biasing means permanently biasing said contact roller elements towards said circumferential surface; and mounting means mounting said mounting arm means for movement circumferentially of said feed roller.

13. In an apparatus as defined in claim 11, said mounting means comprising a curvilinear guideway extending circumferentially of said feed roller, pin means on said mounting arms slidably received in said guideway, and a spring urging said mounting arms with said roller element toward said circumferential surface.

16. In an apparatus for separating fibers from fibrous sliver, in combination, a rotary carding roller; a supply device supplying fibrous sliver for movement in a predetermined path towards said carding roller; contact means proximal to said path upstream of said carding roller; a rotatable feed roller in said path adjacent said contact means and defining therewith a nip zone arranged to receive fibrous sliver from said supply device, said feed roller having an axis of rotation and a circumferential surface an arcuate portion of which extends from said nip zone downstream along said path to the vicinity of said carding roller and defines a sliver control zone in which the sliver travels in engagement with said circumferential surface from said nip zone to the vicinity of said carding roller, said circumferential surface contacting said sliver in said nip zone at one circumferential location of said feed roller and releasing the sliver in the vicinity of said carding roller at an other circumferentially spaced location; and displacing means comprising arms carrying said contact means and being mounTed for movement in a sense effecting displacement of said contact means about said axis so as to shift said nip zone circumferentially of said feed roller and vary the circumferential spacing between said locations; an additional segment-shaped contact element having a projection slidably received in a recess of said support proximal to said feed roller; and biasing means biasing said segment-shaped element toward said circumferential surface of said fed roller.

17. In an apparatus as defined in claim 16, said feed roller having radial flanges at its opposite axial ends; and wherein said segment-shaped element has flanges each of which is adapted to engage one of said radial flanges of said feed roller.

18. In an apparatus as defined in claim 16, said feed roller having radial flanges at its opposite axial ends; and wherein said segment-shaped element has shoulders located intermediate and each cooperating with one of said radial flanges of said feed roller.