US1635263A - Cane-grinding mill - Google Patents

Description

vJuly 12. 1927 l F. FARREL, JR

GANE GRINDINGMILL Filed May 2. 1921 Patented July 12, 1927. j

i UNITED STATES PATENT OFFICE. j

FRANKLIN FARREL, JR., OIE NEW I-IAVIEN,` CONNECTICUT, ASSIGNOR T0y FABREL FOUNDRY & MACHINE COMPANY, OF ANSONIA, CONNECTICUT.

CANE-GRINDING MILL.

Application led May 2,

This invention relates to cane grinding machinery such as employed for the extraction of juice from sugar cane, and it has more particular application tofmills or grinding apparatus of the type .set forth in my application, Serial No. 445,527, filed February 16th, 1921, of which the present application isa continuation in part.

In some of its aspects the invention is especially applicable to cane grinding millsinv which one or more three-roll juice expressing mills having a top roll, a cane roll and a bagasse roll, are preceded by a preliminary crusher having one or more pairs of rolls which crush the cane before it reaches said three-roll mill or mills.

In other aspects the invention concerns particularly the construction and operation of a threerol1 grinding mill. j

One of the objects of the invention is to increase the extractiony of juice in a mill without commensurately increasing the area of roll surface employed.

More specifically, my object is to increase the shredding of the cane stalks in the mill so that the stalks will be more finely divided than heretofore, and will form a mat of fine fibers from which the juice may be more `"readily expressed as the` cane moves through the mill. than has been possible heretofore.

Another purposefof the invention is to provide a three-roll juice expressing mill with a differential drive which produces a friction motion on the cane Vand thereby increases the' shreddingY action on the latter.

Another object of thev invention is to furnish an improved grinding mill having one or more three-roll juice expressing mills ,and one or more pairs vof preliminary crusher rolls.`

To these and other ends the'invention consists in the novel features and combinations of parts to vbe hereinafter describedv and claimed.

In the accompanying drawing: Fig. 1 is a fragmentary side` elevation, partly in section, of a cane mill embodying my improvements; v f

Fig. 2 is a fragmentary side elevation showing the roll driving gears;

Fig. 3 is a view similar to Fig. 1, showing a modified form; y

Fig. 4 is a fragmentary sectional view showing the grooving and spacing ofthe fthe annular' grooves, teeth for hooking ldrawing in the cane so that the latter will 1921. YSerial No. 465,958.

rolls ofthe three-roll mill illustrated in ysired, but in the particular embodiment now under discussion it may be assumed for purposes of description, that the raw cane as 1t comes from the field .is delivered to the vsingle pair of crushing rolls 1() by a suitable conveyor and chute (not shown). The

cane is drawn in and crushed bythe rolls 10, so as to split open the stalks and separate the fibers, and the stalks'then pass directly to the mill B, consisting of the rolls 12, 13

and 14. The cane moves from the crusherV to the mill B over the ordinary inclined bed, i

which I have not deemed it necessary to il- VIuStTate, andenters between the rolls 12 andv 13, which are termed the top roll andcane roll respectively. These rolls crush and: ex? press a portion of the juice from the cane,

' which as it leaves them is deflected upwardly in the customary manner by the well known turn plate 15, so .as to passbetween i the top roll and the bagasse roll 14. It may vbe assumed for purposes of description also, although not necessarily so, that the installation is a large one, capable of handling imany tons. of cane daily, and that the mill B is followed by a plurality of similar juice expressing mills (not shown), there being suitable conveyors or carriers (not shown) between the several juice expressing mills,

in accordance with the usual practice.

The crushing rolls 10 may be of any approved type but preferably they will be provided withl annular grooves, and with longitudinal grooves forming in connection with be fed into the machiney uniformly and expeditiously. A suitable roll forv the purpose is shown in Fig. 5 and isdescribe'd in detailV in my application, Serial No. 445,527, pre-1V viously mentioned." It has a plurality of cir.- cumferential grooves 10a and a plurality of generally longitudinal grooves 10b. The ciry cumferential grooves of each crusher roll mesh with those of the other roll, and the grooves 10" form interruptions in the circumferential grooves and create teeth that are adapted to hook or draw in the cane.

Viththe purpose of increasing the shreddi-n'g effect of the rolls, both of the pi'feli-minary crushei', and f; rc'ea'oll mill, 'and of augment-ing the capacit-y of the machine, a differential motion of one roll relatively to its mate or coacting roll is provided. One roll rotates at a n'iaterially greater surface speed than the roll on the opposite side of the cane stalk. rIhe result is that the fcane stalks are torn apart more thoroughly and more effectively shredded and opened up #so as to separate the individual fibers of the cane to a considerable degree; and by shredding the cane in this manner thefibers are put in a condition in which they will readily give up their juice When they are subjected to the increased squeezing lact-ion of the following rolls.

I believe 'that theb'est results are obtained Where the surface speed of one crushing roll is at least 5% greater than that of its mate or coacting roll, although .I do not Wish to limit myself unnecessarily in this respect. In any case it may be said that in the machine shown in Fig 1, one of the Crusher rolls has a surface-.speed substantially greater than its mate, and one of th'erolls'of the mill B .has a surface speed substantially 10 higher than that of a coacting roll. In the particular form shown inl Fig. 1, the top crusher roll has a surface speed substantially 10% greaterthan that of the lower `crusher roll, and thevtop roll 12 hasa surface speed substantially 10% greater than that of its coacting lower roll 13. In this particular case also, the speed of roll 12 is the same as that of bagasse roll l141. It Will be seen therefore that in the three-roll mill` as in the crusher, `circumfere'ntially gro'oved intermeshing upper and lower rolls have surf-ace speeds which differ substantially from each other. I do vnot Wish to limit myself., hoW- ever, in all of these respects, as'changes may be made in the details Without departure from the principles involved.

In the case under discussion the tivo coacting crusher rolls 10 are of substantially the same diameter; and the three rolls fof mill kIi are all of lsubstantially the same diameter, which diameter will in practice lbe preferi ably but not necessarily slightly greater than the diameter of rolls 10. The diff-erential motion to which I have referred n'iay in such a case be 'obtained by the use 'of intermeshing gears on the roll shafts, having a dissimilar number of teeth. Thevgear 10, by which the upper roll 10 is driven` has a somewhat smaller number of teeth than its coacting gear 17, the difference in the number of teeth being so chosen as to bring about the relative roll speeds desired, the Idiffereter.

ence in this particular case being substantially 10%, as above stated The lower roll 10 is driven by a shaft 18 on which gear 17 is mounted, the gear 16 heilig mounted on the shaft of the upper roll 10. The mill B is driven from a shaft 19 vconnected With v'or carrying the roll 12, 'anda 'gear 20 on said shaft meshes with a gear 21 on the shaft of cane roll 13 and With a gear on the shaft` of bagasse rollflei. In this particular oase,

the gear 21 has a larger number of teeth than the g'ears 20 and 22, such number being so chosen as to effect the drive of the ktop roll 'at a surface speed which is 10% higher 'than that of the cane roll 13.

The grooving of the rol-ls 20, `21 and is shown in Fig. 4f. These'rolls are similar-to those shown in previous application, each being provided with a plurality of annular f.

grooves, although inv this case I'have not shown the top roll .12as provided with lon git-udin-al grooves as in the former clase These `longitudinal grooves mayv be employed, however, if desired, for increasing" the hooking or drawing-in action Vonthe cane and grippingthe saine whilelthe cane passes through -the bitev of thcirolls 12, 13, and then through the bite of the rol- 1s 12, 14.

In the modified form shown in Fi 0'. 3, the

preliminary Crusher A ifs the saine fa-sthat '95 rpreviously described, but in thefthree-.r-oll mill Bf, the caneroll 13a, instead of being of substantially 'the same diameter-as the other rolls of mill B is of somewhat smaller dia It has, .lioweveigthe saine number "of R. P. M., owing to the fact that in th-iscase gears `(not shown) having-fan even number Yof teeth are mounted on the shafts of rolls 12, 13 and intermesln in Yaccordancewith the usual practice. In this manner, as in 'the case previously described, the relative surface speed of the cane roll is decreased. *In

lsuch a mill, also, thesurface speed of the top roll is at least i5% greater than that of the cane roll and 'in this particular case the top roll surface speed is about 10% faster than the cane roll surface speed, asin the 'case previously described.

The operation of the grinding'm'ill will be more or less obvious'from the foregoing de scription. The difference in the surface speeds of the rollsat opposite sidesof the rcane stalk 'produces a sort of tearing motion yon the stalk, which I term la friction motion, `due to the fact that friction is exerted upon vthe stalk by one roll'while .it is lbeing held by the veoacting roll. In the particular form-s shown, the `cane'is held back in a sense by the lower Crusher' roll While it is 'being acted upon frictionally andtorn apartian'd shredded by the upper Crusher roll. In th-'e -mill Bor B', lon the other hand, tlie'top relil has a greater surface speed faud'rvlle th'e stalks are held by the cane roll the' top rolll ribs tear them apart and shred them. in

IUS)

isthe slower one. I do lnot limit myself,

however, to such an arrangement, nor to three-roll mill in which the vtop rollhas a greater surface speed than. another roll.

Various changes in these and otherrespects may be made without departing from the scope of the invention Vas definedin the:

claims. a

It will be understood that as a general rule the crusher rolls are provided with teeth and that the ribs of the upper and lower crusher roll are of the same pitch, corresponding somewhat to the top roll and bagasse roll of the three-roll mill, although usually the pitch is greater than in the case of these particularA rolls of the three-roll mill. The cane roll is set farther apart from the top roll than is thebagasse roll, although the distance between the top roll and cane roll is usually somewhat less than thedistance between the two crusher rolls 10. As the top roll and bagasse roll are set quite closev together, they can exert a lpowerful squeezing action on the cane, and as the cane has been effectively shredded in the Crusher and in the bite of the top roll and cane roll, the squeez-` ing action in the closebite of the top roll and bagasse roll of the three-roll mill is very effective in extracting juice.

It is preferred to increase the surface speed of the top roll relatively to that of the cane roll, in the three-roll mill, on account of the tendency of the faster roll, i. e., top roll, to carry along the cane in the same general direction as the curvature of the upper surface of the turn plate, which thus cleans olf the latter and prevents clogging. I do not limit myself, however, to this feature in all aspects of the invention. By providing a friction motion on the cane between the top roll and cane roll, the cane is better conditioned, by the resulting shredding eect,`

for the subsequent heavy squeezing action, produced by the top roll in combination with the closely set bagasse roll. It may be found advantageous in certa-in cases,`however, to differentiate the surface speeds of the top roll and bagasse roll, respectively, for producing a shredding action which will be of value' in the following mill; and in-such a case, either the top roll'or the bagasse roll may be the faster one. This surface speed diiference, also, may be effected by dissimilar toothing of the gears or by-difference in the roll diameters, as in the cases previously mentioned. y

The Crusher and the three-roll mill are provided with the usual or any preferred hydraulic pressure devices, which I have not considered it necessary to describe in detail, although they are shown in a general way in the drawing. Usually the pressure between the top and: bagasse rolls of the three-rollvmill. is greater than that between the rollsvof the preliminary cruSher. The 'Y pressure inv the'preliminary Crusher may be, say, 25); tons, whereas that in the first threeroll=mill maybe, say375 tons. f V

Y I am. aware Ythat inv prior threeroll and possiblyin preliminary Crushers, kthere have been'surfacevspeed dierences between circumferentlally grooved mtermeshmg rolls.

caused by therunevenwearing of the roll surfaces, in certain instances, and in someY few cases there have perhaps been differences of surface speed resulting from inaccuracy in manufacture or similar causes. In such cases, however, so faras I am advised, the surface speed difference between coacting rolls has not amounted to, say, more than mills, l

one or two percent, usually less, and it has Usually it is more convenient to have the two coactingcrusher rolls of the same diameter and to drive them by gears having a dissimilar number of teeth as described, but it isv obvious that in some cases the diiference of surface speed might be obtained by differences of diameter of the Crusher rolls, as explained in connection with the top and canev rolls of the three-roll mill of Fig. 3. Other changes in this and similar respects may be made wit-hout departing from the scope of the invention as defined in the claims.V Y

What I claim is:

l. A cane mill having a top roll, a cane roll and a bagasse roll, all of said rolls being provided withannular grooves, the grooves of the top and bagasse rolls being of the same pitch but offset so that the ribs of one of said two rolls extend into the grooves of the other, and the grooves of the vcane roll being finer thanv the grooves of the top and bagasse rolls, the top roll and bagasse roll being set closer to each other than to the cane roll, and means for driving the top roll and the bagasse roll at substantially greater' surface speed than that of the cane roll, thereby effecting a frictional shredding action upon the cane passing between the top roll and the cane roll.

2. A cane mill having a top roll, a cane roll having annular grooves therein, a bagasse roll, the top roll and bagasse roll lil() having .approxmately the :same surface rand being set 'einser to each other than the help y1'011 'is t@ the canelolhandmean's for delving the cane roll at 'a ysurface substimtay :slower than that lof the' tep and bagasse r01l's,\the'eby effecting auffietonal shredding 'a'eton upon 5th-e v'Game passing `bet-Ween the top roll 'and Ithe 'cane r0=1=L4 Ina Ycane mill, movng'shreddngmemls l adapted to .have lcame passthereo-ver, said means ,having :a frib'bed Surface, the

movement lof Said eene, and Va pair ofco- @fptratmg 'rolls hav-mg a g1-eater suracej speed vthan Sald'shr'edding means 'and bemg adapted to drag @me over Said ribbed sur# l' face, ene 0i said rolls being :adaptedlto pressi the cane 'against said ribs While being'. drag-geil thereoven. In Witness whereof, I have hereunto seb my ha'ndY on the 28th daye'f Aprl- 1921.,l FRANKLIN FARREL-JR.' y

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