US2719332A - Decorticator - Google Patents

Description

Oct. 4, 1955 c. R. SHORT ET AL DECORTICATO R 2 Sheets-Sheet l Filed June 3, 1952 IN VEN TORS: CHARLES R. SHORT GEORGES P BROUILLETTE Oct. 4, 1955 R. SHORT ET AL DECORTICATOR 2 Sheets-Sheet 2 Filed June 3, 1952 D 0-1 I 2 12b 4- INVENTORS.

CHARLES R. SHORT BY GEORGES BROU/(LETTE "DECORTIGATOR Charles R. Short and Georges P.r Brouillette,.Clermont, .Fla., assignors .tot Floridalndustrial Laboratory, Inc,

Clermont, Fla.

Applicatioritlune lig 1-952, Serial N03 291,501

6 .Claims. (CL: .19.-24)

Our invention relates to*adecorticator adapted for the recovery of textile fibers fromcertain cane plants of the bast fiber familyg-including wsuch' species as jute, kenaf and ramie.

The principal sources-of vegetable fibers in commercial use are either the lea-ves or the stalksbf suitable plants; a distinction maythus be made between leaf fibers and bast fibers. The former are positionedinthe center of the'deaves and-are covered by a fleshy layer which must be scraped otf to expose the fibers; this is -accom- "plishedin practice by passing the leaves between a large wheel having scrapers attachedto itscircumference and -a curved plate having a. surface longer=thanthelongest "fibers.

Bast fibers, on the other hand, are 'located on the outside of a'firmcore-"of pith-*and-wood and-are covered only by a relatively thin layer of bark; they are thus recoverable by-=lstripping them off the core.

Attempts to decorticate bast fiber plants by machines designed for leaf fibers haveyin view of the aforesaid -dissimilarity in plant-structure;been larg'ely unsuccessful; resulting'in crushing; bruising or other injury to the fiber and yielding only a fraction of the theoretical output. It has already been proposed to increase this yield by feeding the canes first from the top end and then from the butt end, for a two-stage processing of the plants from ends toward the center of the stalks. This procedure is time-consuming-and does notreadily lend itself to automatic feeding.

The general objectof our'inve'ntion -is to provide a machine adaptedforthe continuous"decortication of cane plants, with a maximum efliciency in terms both of manhours and of cane input,- and with a yield-of clean and uninjured fibers.

' Other objects, ancillary to the one stated-above, include the provision of means for sofeeding the canes into the machine that the same will not-objectionably overlap and will have the -proper direction whenreaching the stripper mechanism, as well as the provision of means for properly coordinating the speed of the feeder with that of the stripper.

-According to a feature of our invention there is provided a set of feeder rolls, including one or more pairs of such rolls, followed by oneonmore brushing rolls, the first of the latter rolls havingnangularly spaced fins co-operating with a composite deflecting OI? guide plate.

-We have found that the configuration and the position United States PatentfO 2,719,332 Raterited". Oct. 14, @1955 The use of two brushing rolls hasubeen found satis- 1 factory for kenaf and jute; for rarnie the provision of a 1 third brushing roll is preferred. 'Thefins or blades :of the brushing rolls intermesh and overlap to tau certain extent, thereby stroking"thefibers without bruising or of Fig. 2, respectively; and

a section, commonly'referred to as V -grooves. -pair of feed rolls receivesa the incoming st-alks from a t Fig. 5 illustrates a brushing roll-arrangementrepresenting a modification ofthatshown in Fig. 1.

Themachine shown-in Figsx 1- -4 comprises a frame :10 on which there are supported, in. axiallyj parallelhorizontal position, a firstpair oflfeed vrolls 11a, 11b; a second pair offeed rolls 11c) 11d, and apair ofbrushing rolls 12a, 12b. One of the feed rolls of*the first pair, namely=the upper roll 11a, -is:provided= with peripheral grooves 13of roughly triangular--or ttrapez'oidal cross The first conveyor belt 14 onwhich these 'st alks 15 are placed top first, without previous removal -bf' their bnaiiches and leaves. The lower roll 11b of thefirstpair: as twell as the rolls 11c, 11d ofthe second pair are: soft-surfaced Y and comprise a hard core 16, a deep layer 17 of resilient weushioning materiaL such as sponge' rubber; surrounding said core, and a tough-but flexible protective jacket 18, e. g. of abrasion-resisting rubber.

Between the feed r'olls lla lld and the brushing rolls 12a, 12b there is positioned a deflecting plate- 19 which together with these brushing rolls defines the stripper mechanism. This plate has'three angularly adjoining surfaces 19a, 19b and-19c serving, respectively, to deflect the stalks coming from the rolls 11c, 11d to- Ward the first (here the lower) brushing roll 12a, to guide these stalks in such manner as most efiectivelyto assist the fins of this roll in their disintegrating action upon the cores of the stalks, and to provide aconcentric backing surface against which the liberated' fibers may be applied by said fins during-the further processing. Surface 19a, accordingly, lies in a substantially axial plane ofthe roll'12a; surface 1% is upwardly inclined with respect to said plane by an angle of about 20; and surface 19c is curvednand concentric with the pe- =riphery of roll. 12a, terminating just-short ofthe sweep of the blades of companion roll- 12b.

It may be mentioned that in some cases the-two surfaces 1912, 191; may be combined into a single-such surface, extending either axially of the first brushing roll or at some leading angle up to approximately-20. The most favorable results, however, have been accomplished with an arrangement as hereshown and described.

Whereas the fins or blades 20a of roll 12a are shown mprovided with sharp 'edges, those-of companionroll 12b,

provided for collecting the processed fibers 21'and for separating them from the accompanying trash 22. Thus there has been shown in Fig. 1 a high-speed conveyor belt 23 which constantly ejects the loose trash and which hurls the trailing end of each fiber, as it leaves the rolls 12a, 12b, over a horizontal retrieving bar 24, positioned back of the conveyor 23, from which these fibers may be readily gathered for removal from the machine.

Motion is imparted to the rotating members by a motor 25 which is mounted on a bracket 26 at the bottom of the frame and drives a main shaft 27 via pulleys 28, 29 and a belt 30. The feed rolls 11a 11d, the brushing rolls 12a, 12b and the input conveyor 14 are all positively driven from this shaft, via chain drives shown in Figs; 3 and 4. Thus one end of shaft 27 carries a sprocket 31, Fig. 3, which drives a chain 32 engaging four identical drive sprockets 33a, 33b, 33c, 33d, secured to the shafts of respective feed rolls 11a, 11b, 11c, 11d, as well as an idler 34 and a smaller sprocket 35 which is secured to one of the drums carrying the belt 14. The other end of the shaft carries a sprocket 36, Fig. 4, which drives a chain 37 engaging two identical sprockets 38a, 38b, secured to the shafts of respective brushing rolls 12a, 1217, as well as an idler 39. The four feed rolls are thereby' driven in unison, and the two brushing rolls are likewise driven in unison but at a surface speed approximately three times that of the feed rolls. The output conveyor 23 is driven via a step-up transmission comprising a pulley 40 on shaft 27, a belt 41, and a pulley 42 secured to one of the drums carrying the belt 23. The two gear assemblies are enclosed by covers 43, 44, respectively.

The longitudinal stroking action of the high- speed brushing rolls 12a, 12b upon the fibers of the green stalks, in addition to removing adhering woody particles therefrom,also exerts a forward pull upon the fiber layer at a distinct angle to the direction in which the stalks are advanced along the plate surface 19b; thus, the tubular fiber layer will be split at the point where the fibers change direction, i. e. at the junction of plate surfaces 19b and 19c, and this otherwise unbroken and uninjured fiber layer will be stripped off its less flexible woody core at that point, hence at a location at which the core has not yet been subjected to the disintegrating action of the blades 20a. The fibers are, accordingly, recovered without being bruised or crushed, in conformity with the aforestated general object of the invention.

In the particular embodiment illustrated the frame 10 is supported by wheels 45a, 45b, 45c, enabling ready I transportation of the unit into the field for immediate processing of the stalks as soon as they are harvested.

The modification of Fig. 5 comprises a guide plate 119 and three brushing rolls 1126!, 112b, 1120 in lieu of the analogously designated elements of Fig. l. The plate 119 has a horizontal supporting surface 119a, substantially aligned with the axis of the first brushing roll 112a which is here the upper one of the first two rolls, an adjoining guiding surface 11% sloping downwardly at an angle of about 20, and a curved backing surface 119a concentric with the roll 112a. It will be noted that here the stalks 15 do not impinge upon the plate from below but come to rest on the surface 119a after leaving the feed rolls (not shown in Fig. 5). The provision of three rolls as herein shown has been found particularly desirable for the processing of ramie. It will be noted that the blades of rolls 11215 and 1120 intermesh in substantially the same manner as those of rolls 112a (or 12a) and 11212 (or 1211).

The invention is, of course, not limited to the specific embodiments shown and described but is capable of numerous modifications and adaptations within the spirit and scope of the appended claims.

We claim:

1. A decorticator for recovering bast fibers, comprising plate means having two angularly adjoining surfaces, feed means for advancing the stalks of cane Plants along one of said surfaces past the junction of said surfaces, core-disintegrating means beyond said junction co-operating with the other of said surfaces, and brushing means beyond said other of said surfaces adapted to engage the fiber layer of an advancing stalk and to exert a forward pull thereupon in the general direction of said other of said surfaces, thereby stripping said fiber layer from its underlying core at said junction, said core-disintegrating means comprising a first roll having angularly spaced peripheral fins, said brushing means comprising a second, similar roll having fins meshing with those of said first roll, the orbits of said fins intersecting to a depth substantially less than the height of said fins, whereby a clearance substantially in excess of the thickness of the stalks remains between the fins of each roll and the periphery of the respective opposite roll and the cores of said stalks are fragmentized without being crushed.

2. A decorticator according to claim 1 wherein the fins of each roll are in the form of radially extending blades spaced from one another by a distance substantially greater than their thickness.

3. A decorticator according to claim 1 wherein the fins of said first roll have relatively sharp edges and the fins of said second roll have relatively dull edges.

4. In a decorticator for recovering bast fibers, in combination, at least two brushing rolls havingintermeshing sets of peripherally spaced fins, the spacing of said fins at their base being substantially not less than their height, drive means for rotating said brushing rolls in unison, a backing plate concentric with the axis of a first one of said brushing rolls and spaced from the outer orbit of the fins thereof by a distance of substantially the order of magnitude of the thickness of said fibers, and guide means ahead of said backing plate for directing the stalks of bast fiber plants toward said first one of said brushing rolls at an angle to the surface of said backing plate, the fins of said first one of said brushing rolls having relatively sharp edges and the fins of the other of said brushing rolls having relatively dull edges.

5. The combination according to claim 4, including a third brushing roll having fins intermeshing with those of the second of the two first-mentioned brushing rolls.

6. The combination according to claim 4 wherein the axes of the second and of the third brushing roll lie in a plane substantially at right angles to a plane including the axes of the first two brushing rolls.

UNITED STATES PATENTS References Cited in the file of this patent 568,225 Allison Sept. 22, 1896 1,021,269 Schlichten Mar. 26, 1912 1,308,376 Schlichten July 1, 1919 1,520,358 Lowry Dec. 23, 1924 1,790,980 Erb Feb. 3, 1931 1,959,757 Gardner May 22, 1934 2,222,793 Burkardt Nov. 26, 1940 2,293,056 Gardner Aug. 18, 1942

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