Note: Descriptions are shown in the official language in which they were submitted.
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This invention relates to a method and apparatus for process-
ing sugar cane, and in particular to an apparatus and method of processing
sugar cane stalks.
A sugar cane stalk consists of a film of wax on an epidermis
material which covers a harder casing material called the rind, and a core
enclosed by the rind. The core is a softer fibrovascular material and
juices. All elements of the stalk, except the wax, hold juices in varying
quantities and composition, with the core holding the major portion of the
sugar juices, as well as the fibrovascular material consisting of soft
fibres and a cell-like material which, when dried, forms a pith-like
material.
The problems involved in processing a sugar cane are (i)
orientation of the stalks, (ii) cleaning of the stalks, and (iii) milling
of the stalks, i.e., separating of the elements of the stalks to obtain
the sugar juices. These problems are solved with varying degrees of
success by the methods and apparatus disclosed, for example, in United
States Patents Nos. 3,566,944; 3,567,510; and 3,567,511, all issued to
S. E. Tilby on March 2, 1971, and 3,976,498, issued to S. E. Tilby et al
on August 24, 1976.
The object of the present invention is at least partially to
solve the problems encountered with the devices disclosed by the above
mentioned art and by the patents mentioned therein by providing a method
and an apparatus which enable the relatively efficient bulk handling of
sugar cane on a large commercial scale.
Accordingly, the present invention relates to an apparatus for
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processing sugar cane comprsiing:
(a) an inlet station for receiving randomly oriented cane stalks;
(b) a feed control station for controlling the quantit,v of
stalks fed to the r~omainder oF the apparatus;
(c) an aligning station for making a first alignment of said
cane stalks;
(cl) cutter means for cutting said sane stalks into billets~
(e) cleaning means for cleaning said billets;
(f) hopper means for receiving said billets;
(g) billet aligner ancl delivery means for algining said billets
or subsequent processing and including means for damping
tumbling cf said billets; and
(h) separator means for separating the cane into epidermis, rind
ancl pith componellts.
The in~/ention also relates to a method of ~rocessing su~ar cane
comprising the steps of:
(a) introclucing randomly oriented cane stalks into a processing
ap~ aratlls;
(b) controlling the quantit,V of stalks fed to the remainder of
the apparatusi
(c) aligning said stalks, whereby the longitudinal axis of
the stalks are aligned in substantially the same direction;
(d) cutting said stalks into billets;
(e) cleaning said billets.
(f~ aligning said billets~ and
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(g) separating said billets into epidermis, rind and pith
components.
The apparatus and method described abcve, meter, thin out and
align sugar cane stalks prior to chopping of the stalks into billets.
Foreign matter, leaves and cane stools are separated from the stalks as
part of the cleaning step in the process. Some of the important features
of the invention are the uniform flow of cane stalks or billets, the elim-
ination of surges of cane billets to aligning and separation units, and
the efficient cleaning of the stalks. By cleaning is meant the separation
of extraneous material such as stones, metal, dirt and other debris, and
the washing of the cane stalks to remove sand or mud therefrom.
The following are significant features of the invention described
and claimed herein.
At the inlet end of the apparatus cane stalks are fed to an
inclined conveyor and during passage along such conveyor, are engaged by
a comb back conveyor, i.e., a conveyor including tines or fingers extending
outwardly from its flights. The comb back conveyor moves in a direction
opposite to the direction of travel of the stalks on the inclined conveyor.
By adjusting the gap between the comb back conveyor and the inclined
conveyor, the quantity of cane passing to the remainder of the apparatus
is metered.
After leaving the inclined conveyor, the randomly oriented cane
stalks are aligned by allowing them to fall into a chute, one side of which
is vertical and the other side of which is inclined, so that the cane stalks
slide down the sloped side of the chute to a conveyor thereby becoming aligned.
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At this point some foreign bodies and in particular stones,
and ferrous objects are removed from the cane by passing the cane over a
gap between two conveyors, the leading end of the second of which is
lower than the trailing end of the first conveyor. The gap between the
conveyors is substantially greater than the anticipated trajectory of
foreign objects such as stones, so that the objects drop from the cane
flow. By making the roller at the trailing end of the first conveyor
magnetic, some metal objects can be removed from the cane flow.
The cane stalks are cut into sections or billets, which are
caused to move down an inclined slide while air is blown vertically
through the cane to remove leaves, dust and other extraneous material
from the cane.
The prevention of the formation of tunnels through the billets
and the resulting lowering or stopping of cane flow is achieved by means
of an elongated hopper, and a swing conveyor is provided For feeding the
billets to such hopper. The hopper is provided with a plurality of drag
chains, and is designed in such a manner that tunnelling does not occur,
as is often the case with a hopper having a V-shaped bottom. The hopper
includes vertical divider plates or partitions and walls inclined in
such a manner as to ensure movement of the cane billets downwardly onto
the drag chain conveyors.
Before reaching the separators the cane billets are distributed
and metered, and surges in the quantity of cane delivered to each
separator is eliminated by feeding the cane billets to a cascade of
sloping plates, one of which pours the cane billets onto another sloped
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plate to spread the cane heaps delivered by the hopper drag chain
flights.
Finally, the cane billets are fed to a final alignment and
delivery unit for feeding into separators. During charging of the sep-
arators the cane billets travel through arcuate chutes containing a
perforated plate or grill followed by a set of permanent magnets. Air
is blown through the grill across the path of travel of the cane billets
to effect a final cleaning. The magnets provide a final protection against
the introduction of iron objects into the separators. During this stage
of the operation the cane billets can be diverted away from the separators
to prevent over-loading of the separators. Any diverted cane billets
are re-circulated~ i.e., returned to the portion of the apparatus immediately
preceding the cleaning tower.
In the apparatus of the present invention, all belt drives may
be replaced by chains and gears. Moreover, the core milling drums used
in the separators may be driven directly from a power source~ which
eliminates power loss encountered when using an indirect drive. The
complete power transmission system of the invention is enclosed, which
facilitates adequate lubrication, while preventing wear producing contam-
ination. Such an arrangement permits higher operating speeds and results
in a minimurn of maintenance. By using flywheels mounted on the shafts of
the core milling drums in the transmission, the normally fluctuating
loads on the core milling drums and drives are smoothed out.
In the separators, rind material is diverted away from the exit
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oF the nip between the milling and feed clrums, and the direction of the
flow of such rind is controlled. Thus, the core material is permitted to
expand and travel away from the nip between the milling and feed drums
which reduces the load on the milling drum caused by back pressure of core
material, as is the case when the core material is diverted.
The invention will now be described in greater detail with
reference to the accompanying drawings, which illustrate a preferred em-
bodiment of the invention, and wherein:
Note: All views of the accompanying drawings are schematic.
For the sake of brevity and easy reading the word "schematic" has been
omitted in the description of the figures. In the drawings, for the most
part, the expression "longitudinal section" is intended to mean a sectional
view taken in a plane incorporating the longitudinal axis of an element, and
by "cross-sectional" is meant a sectional view in a plane perpendicular to
the longitudinal axis of the element. In general, for individual elements,
the proper terms are used, particular with respect to Figures 15 to 26.
Figure 1 is a partly sectioned" side elevation view oF a sugar
cane processing apparatus in accordance wilh the present invention;
Figure 2 is a perspective view of input control conveyors used
in the apparatus of Figure 1;
Figure 3 is a perspective view of the input end of a cane
orienting section of the apparatus oF Figure 1;
Figure 4 is a partly sectioned, side elevation view of the cane
orienting and initial cleaning section of the apparatus of Figure 1;
Figure 5 is a sectional view of a cleaning tower for use in the
apparatus of Figure 1;
Figure 6 is a cross-sectional view of the tower of Figure 5;
Figure 7 is a plan view of the trailing end of the apparatus
of Figure 1;
Figure 8 is a perspective view from above and the leading or
input end of a billet aligner and separator for use in the apparatus of
Figure 1;
Figure 9 is a longitudinal sectional view of a surge prevention
chute and the billet aligner of Figure 8;
Figure 10 is a cross-sectional view of the leading end of the
billet aligner of Figures 8 and 9;
Figure 11 is a cross-sectional view of the billet aligner of
Figures 8 to 10 near the leading end thereof;
Figure 12 is a longitudinal sectional view of the upper input
end of the separator of Figure 8;
Figure 13 is a perspective, partly sectioned view of the sep-
arator of Figure 8 from one end and above;
(Note: Except for Figure 27, the remaining Figures of the
drawings illustrate elements of the separator of Figure 13),
Figure 14 is a 10ngitudinal section of a rind reflector and
guide plate;
Figure 15 is a longitudinal sectional view of a milling drum;
Figure 16 is a partly sectioned, end view of the drum of Figure
15;
Figure 17 is a plan view of the body of the milling drum of
-
Figures 15 and 16;
Figure 18 is an end view of the body of Figure 17;
Figures 19 and 20 are cross-sections of portions of the peri-
phery o-f the milling drum of Figures 15 to 18;
Figure 21 is an end view of one end plate for use on the drum
of Figures 15 to 20;
Figure 22 is a cross-section taken generally along line 22-22
of Figure 21;
Figure 23 is a perspective cross-sectional view of another end
plate for use on the drum of Figures 15 to 20;
Figure 24 is a longitudinal sectional view of a milling or feed
drum mounting arrangement;
Figures 25 and 26 are cross-sectional views taken generally
along lines 25-25 and 26-26, respectively of Figure 24; and
Figure 27 is a perspective view of a transmission unit for
driving the separator of Figures 13 to 16.
For the sake of brevity, when describing the apparatus of the
present invention, whenever possible the method of using such apparatus
will also be described. ;
With reference to the drawings, and in particular to Figure 1,
the apparatus of the present invention includes eleven basic sections, gen- ;
erally indicated by the numbers 1 to 11 in Figure 1. The sections include
an inlet or input section 1, where sugar cane is introduced into the ap-
paratus. Following introduction into the apparatus, the stalks of sugar
cane are fed through a feed control section 2, which meters the quantity of
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cane being -fed to successive sections of the apparatus. The cane dis-
charged from the feed control section 2 passes through an aligning and
first cleaning section 3, where at least some of the foreign matter in
the cane is removed and the stalks are thinned out prior to being fed
into a cutting or billeting section 4. After cutting, the stalks are
fed into a cleaning tower 5 for air and magnetic cleaning. The cleaned
billets then pass through a distributing chute and rotating swing conveyor
6 to a distributing hopper 7. From the hopper 7 the billets pass through
surge eliminating chutes 8 to billet aligner and delivery units 9. The
units 9 deliver the billets to separators 10 where the epidermis, rind and
core are separated and discharged via discharge section 11.
Referring to Figures 1 and 2, whole sugar cane stalks are dumped
onto a conventional, horizontal cane conveyor 12. Using stop-start control
of the conveyor 12, the cane stalks are fed in controlled quantities to an
inclined cane conveyor 13. The conveyor 13 is operated by a variable speed
control (not shown) and normally moves faster than the preceding conveyor
12. The effect is to remove reasonably uniform quantities of cane from the
mass of cane stalks piled on the first conveyor. The conveyors 12 and 13
are controlled by an operator at the inlet end of the apparatus. Metering
of the cane stalks in a layer of uniform thickness from the conveyor 13 is
effected using a comb back conveyor 14, which is located above the conveyor
13. As illustrated by arrows 15 and 16 in Figure 2, the conveyor 14 is
intended to travel in a direction opposite to the direction of travel of the
conveyor 13 and the cane stalks. The end 17 of the conveyor 14 closest to
the inclined conveyor 13 can be rotated around a horizontal axis defined by
the roller shaft 18 at the other end of the conveyor 14. Vertical movement
of the end 17 oF the conveyor 14 is effected by a hydraulic cylinder 18 ex-
tending downwardly from a frame 20. A piston rod 21 of the cylinder 19 is
connected to the top end of a yoke 22 in which roller shaft 23 is rotatably
mounted. Thus, the distance between the conveyors 13 and 14 can be varied
for controlling the thickness of the layer of cane passing between the con-
veyors. A plurality of tines 24 project outwardly from the flights of the
conveyor 14 for combing back the cane stalks.
From top end 25 of the conveyor 13, the cane stalks fall between
two walls 26 and 27 of the chute 28 (Figure 3). The wall 26 is vertical and
other wall 27 is inclined. Thus, any cane stalks tending to bridge the gap
between the walls 26 and 27 finds no support on the vertical wall 26, and
thus falls onto an alignment conveyor 29 at the bottom of the chute 28. The
inclined wall 27 of the chute 28 reduces the width of the cane flow to the
width of the conveyor 29. The speed of the conveyor 29 is substantially
higher than the speed of the conveyor 13 for thinning out the layer of cane
stalks.
As best shown in Figure 4, the stalks are fed from conveyor 29
to a slightly upwardly inclined conveyor 30 which is located beyond and
slightly below the conveyor 29. Because the cane stalks are aligned in the
direction of travel of the conveyors 29 and 30, the stalks may project be-
yond the end of the conveyor 29 without tipping. Moreover, the momentum of
the stalks carries them beyond the end of the conveyor 29 before appreciable
tipping occurs. Thus, there can be a gap between the conveyors 29 and 30
for removal of stones 31 and metallic objects 32 from the cane stalks 33.
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In order to remove the metallic objects 32, roller 34 at the trailing end
of the conveyor 29 is a conventional magnetic belt drive roller. The debris
removed from the stalks 33 falls through a downwardly tapering chute 35 onto
a conveyor 36 which is normal to the direction of travel of the stalks 33
for suitable disposal.
From the conveyor 30, the cane stalks 33 are fed between the
rollers of a conventional twin roller-type cutting or chopping machine 37
(Figure 1), where the stalks are chopped into billets of a predetermined
maximum length. Such length is determined by the speed of cane flow, the
number of blades on the chopper rollers, and the speed of rotation of the
latter. The cane billets thus produced are fed to a horizontal conveyor 38.
The conveyor 38 also receives trash and rejected cane from a return conveyor
39, which is described in greater detail hereinafter. The conveyor 38 is
also the receiving conveyor for cane already chopped by cane harvesters
(not shown).
From the conveyor 38, the cane billets are fed onto leading end
~0 of an inclined conveyor 41, and are delivered into the top end of the
detrashing or cleaning tower 5 (Figures 1, 5, and 6). The tower 5 contains
an inclined, perforated plate 42. Cane billets flow down the plate 42 in
the direction of arrows 43. During such downward movement, air from blowers
44 goes upwardly through the plate 42 and the cane billets in the direction
of arrows 45. As best i11ustrated in Figure 5, air flowing upwardly through
the plate 42 and the billets removes trash and dust from the descending
billets, and passes upwardly over a central divider 46. The speed of the
air is such that the cane billets tumble and float down the plate 42 on a
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cushion of air. Of course, the force of the air is not sufficient to re-
move cane billets with the debris. The air ladened with trash and dust
passes over the divider 46 and descends between spray nozzles 47, which
project a fine spray of water across the path of the air. The water wets
S the dust and debris to prevent discharge of such material into the atmos-
phere, and helps to create a downdraft by cooling the air. The downdraft
reduces the back pressure of the air, and thus reduces the possibility of
dust and debris leaving the tower via the cane billet inlet and discharge
openings. The wet dust and debris falls into a trough 48. A drag chain-
type conveyor 49 in tne trough 48 removes debris for disposal, i.e., to a
truck 50. The water collected by the trough 48 is recirculated into the
cleaning section of the tower through a duct 51, and a pump and filter unit
52. The water pressure in the unit 42 is maintained by introducing water
through line 53 and valve 54.
Billets reaching the bottom end of the plate 42 pass over per-
manent magnets 55, which are disposed in a line transverse to the path of
travel of the billets. The magnets remove any iron objects left in the
cane. The cane billets are then deflected by an inclined plate 56 onto the
leading, bottom end of an inclined conveyor 57. The plate 56 reduces the
speed of travel of the billets, and tends to eliminate surges in the
quantity of cane flow.
The conveyor 57 delivers the cane billets to the distributing
chute and swing conveyor 6 (Figures 1 and 7). The chute and swing conveyor
6 are mounted on a tower 58, and include a chute 59 for delivering the
billets to the leading end of a horizontal swing conveyor 60. The conveyor
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is pivotally mounted on the tower 58 for rotation around a vertical axis,
so that the discharge or trailing end 61 of the conveyor can be rotated
through a large arc 62 for distributing cane billets to any of a plurality
of sections 63 of the distributing hopper 7. The conveyor 60 can be set
in one position or travel in a smaller arc, depending on the number of
separators 10 in use. The hopper 7 is designed to meter, i.e., feed pre-
determined amounts of cane billets to the separators 10. As mentioned
hereinbefore, with hoppers having V-shaped bottoms, it is possible for the
drag chain conveyor used to extract the cane billets from the hopper to form
a tunnel through the cane which results in the reduction or cessation of
cane flow from the hopper. Such tunnelling is prevented in the present case
by the use of a drag chain conveyor 64 in each section 63 of the hopper,
which conveyor moves horizontally under the billets before rising to the top
of the hopper. Moreover, the three surfaces 65, 66~ and 67 defining the
sides and bottom of the hopper sections 63 are inclined towards the horiz-
ontal port.ion 68 of the conveyor 64. The fourth side 69 of each hopper
section 63 is vertical to prevent cane billets bridging over the conveyor
64.
The hopper drag cha;n conveyors 64 include spaced apart flights~
whereby only a predetermined quantity of cane billets are delivered from
each section of the hopper. By varying the speed of the conveyors 64, the
quantity of billets fed to the separators 10 can be accurately controlled.
The conveyors 64 deliver the billets to inclined conveyors 70 which feed
the billets into surge elimination chutes 8 (Figure 9). Each surge elimina-
tion chute 8 includes a casing 71 containing a pair of inclined surfaces
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72 and 73. Billets entering the surge elimination chutes 8 slide down the
surface 72 cascading against the surface 73. The result is an even flow of
cane billets. The flow of billets is rendered uneven by the hopper drag
chain conveyors 64, which dump the cane billets in heaps onto the conveyors
70. A bank of permanent magnets 74 is provided at the trailing end of the
chute 72 as added protection against iron objects being fed into the sep-
arators 10.
Billets passing through the chutes 8 are fed into billet
aligners and delivery units 9 (Figures 1 and 9 to 11). The units 9 are
designed to align billets longitudinally in the direction of travel of an
aligner conveyor belt 75 in the bottom of each casing 76 of the units 9.
This is accomplished by allowing the cane billets to land on or between
the partitions 77. The partitions 77 slope downwardly to meet a set of
horizontal partitions 78. As the cane billets land on the sloped down
partitions, a portion of them will tumble down to land on the horizontal
partitions 78. This is done to increase the area where the cane billets
land and therefore the capacity of the aligner unit. The horizontal par-
titions 78 and sides 79 of the aligner are inclined, converging downwardly,
so that the gaps between them immediately above the conveyor 75 is much
less than the average length of the billets. Thus, any billet falling be-
tween the partitions 77 will assume a position roughly parallel to the
partitions 78 and sides 79 in line with the desired direction of flow. The
heights of the partitions 78 differ from each other so that any cane billets
landing across a pair of partitions will tend to tip and fall between the
partitions. To further ensure that the cane billets do not remain lying
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across the horizontal partitions, the top of each partition 78 is covered
by a moving, double "V" belt 80, running in a track 81 which is mounted
in a bracket 82 on the top of the partition 78. The tension on the belts
80 can be adjusted by brackets 83 at the trailing end of the belts. The
belts 80 are driven from the leading end, so that the belts move in a
direction opposite te to the flow of the cane flow, and at different speeds.
The different speeds of the double "V" belts 80 will cause one end of
any billet lying across a pair of partitions to travel faster than the
other end, thereby moving the billet into alignment with the space between
the partitions, eventually causing the billet to fall to the surface of
the conveyor belt 75. By moving belts 80 in a direction opposite to the
flow to the conveyor 75, any billets lying across or hung up on the belts
80 will be moved out of the flow area, thus reducing any chance of an
accumulation of billets on top of the partitions 78. Some cane billets,
not quite chopped through will tend to loop over a partition 78 and
impede cane flow. The belts 80 will also remove such billets. Upon
reaching end 84 of the aligner opposite billet discharge 85, such looped
over billets are chopped free by revolving knives 86 located close to one
side of the belt 80. After being chopped free, the billets drop onto the
conveyor 75 and are taken back into the cane flow. Upon hitting the
conveyor 75 some billets will somersault down the surface oF the conveyor
and may cause jamming at cane delivery chute 87 (Figures 1, 8 and 12).
In order to prevent such jamming, strips 88 of flexible material are
provided between the partitions 78 and sides 79 of the aligner. The
strips 88 are secured above the surface of the conveyor 75. The flexible
6~
damper strips 88 are situated immediately downstream from the trailing ends
of the belts 80. The effect of the flexible strips 88 is to stop any
billets from somersaulting and smooth any overlapping billets into a single
layer. From the cane billet aligner unit 9, the aligned cane billets are
propelled from the end of the fast moving aligner conveyor 75 onto the in-
side surface of the downwardly curving chute 87. The chute 87 changes the
direction of flow of the billets from the horizontal to the vertical. The
interior of the chute 87 is divided by parallel partitions 89 (Figures 8
and 12), aligned with the partitions 78 of the cane aligner unit 9. The
partitions 89 ensure that the billets are kept approximately aligned in the
direction of flow since perfect alignment is not crucial. The cane billets
will be processed by a separator 10 misaligned, without affecting the sep-
aration. The vertical portion of the chute 87 includes perforations 90, so
that air from a blower 91 can pass through the chute. The air gives the
passing billets a final detrashing, removing any leaf material, dust, etc.
knocked loose in that portion of the apparatus following the tower 5. The
speed of the air is kept low enough not to divert the billets from their
line of flow. Immediately below the detrashing section of the chute 87,
the billets move past a bank 92 of permanellt magnets. The magnets 92 are
situated in this position to give maximum protection to the separator 10
against any iron items being introduced. The debris removed by the air
from the blower 91 is carried away by a chute 93 to a conveyor 94, and then
to return feed conveyor 39 mentioned hereinbefore. Thus, the debris returns
to the tower 5. As well as disposing of the trash, the return conveyor
system returns odd billets which are sometimes ejected at the entrance to
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the separator lO. Should a power Failure occur, or a mechanical problem
develop in the separator 10, or in the system from the seoarator, cane
jamming would develop very rapidly. To avoid such a condition plates 95
are provided in the interior curved section of the chute 87. The plates
95 are pivoted at their upper ends on pins 9~. The plates 95 extend
downwardly to the perforations 90. The plates 95 are actuated by means
of a ram 97 which moves the plates away from the normal direction of cane
flow into the separator 10 and directs the cane flow into the trash disposal
chute 93 and thence back to the tower 5 for re-circulation into the supply
system to the cane separators 10. The ram 97 may be actuated automatic-
ally by any overload condition after the feed chute 87 of the type caused
by a power failure or mechanical problem or can be operated manually by
the operator.
The vertically aligned billets from the chute 87 enter casing
98 of the separator 10 through in inlet opening 99. The billets are then
gripped by a pair of spaced apart feed drums 100 (Figures 12 and 13). The
drums 100 are Formed of a flexible material and include peripheral surf-
aces with spikes 101 projecting very slightly above the surfaces of the
drums. The spikes 101 ensure a positive grip on the rind portion of the
cane billets. The rotating feed drums 100 drive the billets onto the sharp
edge of a splitter blade 102. Once the splitting process has started on
a billet the diverging surFaces of the blade 102 force the parts of the
billet apart and complete the splitting process. The two pieces of cane
billet are then diverted by two diverging slide plates 103 to close the
gap between core removal or milling drums 104 and core milling feed drums
105. Because the core milling and feed drums will not grip anything but
below average thickness of split cane billets, a positive feed is obtained
by a feed drum 106, which has a flexible surface with spikes 107 project-
ing very slightly above the surface thereof. The spikes 107 engage the sur-
face of the rind. The drum 106 is positioned above the surface of a slide
plate 103 and close to the trailing end thereof. There is a gap between
each plate 103 and drum 106 so that the cane is gripped by the flexible
surface and the spikes 107 of the drum. The feed drum 106 drives the cane
halves into the nip of the core removal and feed drums 104 and 105, respect-
ively. Another reason for employing the feed drum 106 is that any small
pieces of cane arriving at the gap between the drums 104 and 105 will bounce
around in the area of the gap and if permitted will cause a build up. With
positive feed of the split cane halves the ends of the halves drive the
small pieces into the gaps, avoiding jamming the cane in this area. As the
cane halves feed through the fixed gap between the drums 104 and 105 the
cane stalk is gripped by the teeth of the Feed drum 105 and because the stalk
is flattened at the gap, milling drum blades 109 remove the softer core of
the cane from the relatively hard fibres oF the rind. The milled pieces
of core material are ejected down surFace '111 of a deflector 112 onto a
core receiving conveyor 113 (Figures 1 and 7). Meanwhile the rind strips
are deflected by the edge 114 of the deflector 112, and are guided by the
deflector 112 into a gap between an epidermis milling drum 115 (Figures 13
and 14) and an epidermis milling feed drum 116. Epidermis milliny feed
drum teeth 117 grip the core side of the rind strip while blades of
the rotating milling drum 115 strip the wax and epidermis material
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in the direction of arrows 119. Such material is ejected over the top of a
rind deflector 120 through a delivery chute 121 and onto wax/epidermis
receiving conveyors 122 and 123. Meanwhile~ the rind strip 125 is de-
flected downwardly out of the line of flow of the epidermis material by
the deflector 120. In order to guide the rind strips 125 in the desired
direction, as may be required by different installations3 or width of con-
veyors, the deflector 120 includes adjustable plate 126. The plate 126 is
pivotally mounted at the leading end thereof on a pin 127, and can be
locked in position by a bolt 128, which connects a bracket 129 to an
attachment plate 130. The bracket 129 includes an arcuate slot 131 so that
the position of the plate 126 can be adjusted. The rind passing the de-
flector 120 ancl plate 126 is fed through ducts 132 to a conveyor 133 for
discharge from the apparatus.
The core milling drums 104 are structurally similar to the
epidermis milling drum 115. Accordingly, only one drum 104 will be de-
scribed in detail, it being understood that the same description applies to
the other milling drums.
With any type of drum requiring the removal of blades for re-
placement or sharpening purposes and with the requirement that the blades
be replaced to an exact drum diameter concentric to the axis of rotation,
it is normal to reinstall the blades using jigs and/or measuring devices.
Moreover, a trained technician is required to carry out this type of work.
The use of jigs or other instruments and a technician also introduces the
possibility of errors in the installation oF the blades. Jigsg measuring
instruments and/or skilled personnel are not required with the milling drums
_ ~9 _
of the present invention. Blades can be installed quickly. Moreover,
lengths and heights may vary slightly, the drum balance being the deter-
mining factor for the amount of blade variation, without affecting the
correct installation of the blades. By presetting the drum diameter to
the diameter required for, each drum installation, the apparatus may be
designed so that the drum shaft or bearings need not be adjustable to set
the milling blades at a required distance from another part of the machine,
such as another drum. Thus, it is possible to enclose completely all
drives for lubrication, cleanliness and safety. Moreover, no skill is
required for adjusting shafts or other parts of the apparatus.
The milling drum 104 (Figures 15 to 26) includes an elongated,
cylindrical body 135. Slots 136 extending along the length of the body 135
receive and retain the milling blades 109. In the drum, narrow additional
slots 137 are provided between pairs of blade slots 136, so that sides 138
of the slots 136 can flax away from and against the blades 109 to secure
the blades firmly in position, without any movement under load. The spring-
ing of the metal sides 138 is accomplished by providing threaded holes
spaced apart along the length of the narrow slots 137. The holes may be of
two types, namely holes 139 (Figures 17 and 19) with a tapered thread, so
that when set screws 140 are tightened into the hole 139, the metal sides
138 are forced apart to grip the sides of a pair of the blades 109. Alter-
natively, holes 141 (Figures 17 and 20) can be threaded normally for re-
ceiving slot expansion screws 142, which have heads 143. The screw 142
is screwed into the upper end of the hole 141 which is also tapered. Thus,
by wedging action, the sides 138 are forced apart to grip the sides of the
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.
milling blades 109. The blades 109 are positioned concentrically and ad-
justed to the desired drum diameter by drum end plates 144 and 145. Each
end 144 (Figures 15, 21, 22 and 24) and 145 (Figures 15, 23, and 24) is
designed so that when the inner corner of each blade 109 contacts an in-
clined annular surface 146, the blade 109 slides outwardly on such surface
until the other corner of the blade meets the inner surface of a tooth 147.
The inside diameter of each end plate 144 and 145 at the teeth 147 is
exactly that required for the particular drum 104, and the teeth 147 are
concentric with the axis of rotation of shaft 148. The slots 150 between
the teeth 147 permit the excape of material which would be trapped by an
uninterrupted annular flange. The teeth 147 are also a safety feature,
becaurse they form a positivie stop, preventing any blade 109 leaving a slot
136 under the centri-fugal load imposed on the blade by rotation of the drum
104. The end plates 144 and 145 are located on the ends of the body 135 by
dowel pins 151 (Figure 16) in holes 152 (Figures 21 and 23). The end plates
are secured to the body by screws 153 passing through holes 154 in the plates.
The end plates 144 and 145 are provided with threaded holes 155, which are
used for the plate extraction bolts (not shown). When the bolts are screwed
into the plate 144 or 145, they bear against the body of the drum and with
continued screwing, force the plate away from the drum body 135. The front
end p1ate 145 is designed so that screws 156, when screwed into holes 157
in the end plate, contact the inner corner of the blades 109. Because the
screws are at an angle of approximately 45 with respect to one end 158 of
the blades, they force the blade in two directions, namely ~long the slot
136 and outwardly towards the inner surface of tooth 147 on the rear end
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plate 144. When the other end 159 of each blade 109 comes to a stop in the
rear end plate 144, the screw 156 then forces the other corner of the front
end 158 of the blade against the inner surface of the tooth 147, locking
the blade 109 in the operating position. Thus positioned blades 109 are
then clamped tight in their slots 136 by tightening the slot expanding
screws 140 or 142.
The drums are centered on the separator shafts by using one
piece rear cones and segmented front cones. A rear cone 161 (Figures 24
and 26) is assembled on drum shaft 148 and is prevented from turning on the
shaft by a locking key 162. The tapered surface 163 of the cone 161 bears
against the tapered surface 164 of the drum body 135 (Figure 24), which is
prevented from rotating on the cone surface by a locking key 165 on the
cone for engaging locking keyway 166 (Figures 15, 21, and 22) of the drum,
and the rear end plate 144. A front segmented cone 168 is defined by two
segments 169 with an annular groove 170. The groove 170 allows the segments
to be placed over an annular flange 171 of a drum retaining nut 172 prior to
the nut 172 being tightened on the shaFt 148. Upon tightening the retaining
nut 172, the annular flange 171 of the nut engages annular surFace 173 of
the split cone 168 to force the segments against inner, tapered surface 174
of the drum body 135. This centers and locks the drum in the operating
position. Upon removal of the drum 104, the retaining nut 172 is backed
off from the inner surface 173 of the cone 168, and the flange 171 of the
nut engages flange 175 of the cone 168 for removing the cone from the drum.
The ends 176 of the drum shafts 148 are supported by bearings
177 and are retained in bearing housing 178 by a bearing retaining and
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~5f~
mounting plate 179. The retaining plate 179 complete with housing 178 and
bearing 177 is connected to a tail end bearing and housing assembly mount-
ing plate 180 (Figures 13 and 24) by bolts 181. The mounting plates 180
are designed to mount a pair oF bearing housing assemblies belonging to
drums that are paired on the cane separator machine, such as the cane core
remover feed drum 105 and the cane core removal drum 104~ This ensures
that the same bearing and mounting plate assemblies are mated with the same
shafts each time. Thus, any prob1ems of bearing misalignment which could
occur with single housing assemblies being reassembled on different shafts
is obviated. All of the bearing housing plates and housing mounting plates
are dowelled to ensure accuracy of location in a manner similar to the
dowel pins 151 on the milling drum assemblies (Figure 16).
The ends 176 of the drum shafts 148 are threaded internally at
183 for attachment o-f a drum removal device (not shown) which permits re-
moval of the drums from the apparatus without the use of lifting tackle.
Referring now to Figure 27, the power transmission section of
each separator 10 is designed so that all shafts have fixed locations, and
all drives are totally enclosed. Thus, chain drives may be used. The chain
drives can have a sufficient supply of lubrication in the transmission
casing 185 and can be kept free from the damaging effects of dust and debris.
The input drive for the low speed feed drum system is supplied
by a motor 186 (Figure 8), or by a steam turbine (not shown) through a gear-
box (not shown). The power is transmitted to the input shaft 187 through
a transmission unit 188 (Figure 8), such as a standard type of torque lim-
iter, fluid drive clutch or flexible coupling. A suitable chain sprocket
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189 or 190 is provided on the input shaft 187 for variations in speed
caused by the power source, such as is the case with an electric motor
running on a 50 hertz current as compared to a motor running on a 60 hertz
current. In such case, there is an approximate difference of one-fifth
between the revolutions per minute as required by the electrical current
cycles per minute. From the input shaft 187, the power is transmitted to
idler shaft 191 by a chain 192. A chain 194, from the idler shaft 191
transmits power to right hand splitter slide drum shaft 195. From the shaft
195, power is transmitted by a chain 196 to right hand splitter feed drum
shaft 197. A1so from shaft 195 a chain 198 transmits power to the core
milling drum feed shaft 199 and to the epidermis milling feed drum shaft
200. By means of a pair of gears 201 and 202 power is transmitted to
splitter slide feed drum shaft 203, and, at the same time, the direction oF
rotation of this shaft is reversed by the gears 201 and 202. From the
shaft 203, power is transmittecl by chain drive 206 to the core milling Feed
drum shaft 207 and to the epidermis milling feed drum shaft 208. Power is
transmitted by chain 209 from the epidermis feed drum shaft 200 to an oil
lubrication pump 211. The pump 211 supplies oil th,^ough the spray nozzles
212 for lubricat;on of the high speed chain drives between the core milling
and epidermis milling drum shafts. The remainder of the drives and bear-
ings are lubricated by oil mist and splash from the sump of the power
transmission section. The oil level 213 is sufficient for the lower chain
drive sprockets to be partially immersed in the oil, thus supplying the oil
splash and mist for lubrication. Because of the highly fluctuating loads
on the core milling drum shafts 214 and 215 (Figures 13 and 27)3 flywheels
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216 and 217 are provided on the shafts to even out loading, and reduce
power requirements and strain on the drives, and, in the case of an
electric motor power source avoiding high, undesirable electric current
surges. The flywheels 216 and 217 are also mounted inside the power trans-
mission section. Flywheels are not required for the epidermis milling drum
shafts 210 and 218 since the drums themselves have a sufficient flywheel
effect for the far lighter fluctuating loads of such drums compared to those
on the core milling drums. The chains 219 and 220 provide drive from the
core milling drum shafts 21~ and 215 to the epidermis milling drum shafts
218 and 210, respectively.
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