Note: Descriptions are shown in the official language in which they were submitted.
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STATE OF ISRAEL - MINISTRY 0~ AGRICULTURE
APPARATUS AND METHOD FOR SEPARATION OF AGRICULTURAL PROCUCTS
FROM CLODS AND OTHER SPURIOUS MATE~IAL~.
FIELD OF THE INVENTION
The present lnventlon relates to agrlcultural machinery
generally and more particularly to apparatus for separatlng
agr1cultura1 products from other materlals.
BACKGROUND OF THE INVENTION
The separation of agrlcultural products such as potatoes
from clods and stones has long been recogni~ed as a practical goal
of designers of agr;cultural mach1nery. For example, in Agricultural
Engine~ring Recor~l, W~rlt~ 1947-8 p~blish~d by the National Institute of
Agricultural h~gineer~ng, Silsoe, Bedfordshi:re, U.K. at pp. 35-43 there appear~;
a discusslon of efforts, albelt unsuccessful, to des1gn separation
of this type. In thls artlcle, lt ls mentloned that differences
ln speciflc grav1ty and d1fferences 1n reslllence are consldered
to be sultable bases for dlfferentlat1ng between the agrlcultural
products and other materlals. At pages 37 and 38 of the artlcle there
appears a descrlptlon of experlments carrled out using a p1ywood
roller onto whlch were dropped, after s1idlng on a chute, a m~xture
of potatoes and stones while the roller rotated slowly. Some
separatlon occurred but only w1th regularly shaped potatoes and
stones, whlch does not occur ln nature.
Addlt10nat experlments were carrled out using a delivery
chute along whlch the stones and potatoes s11d lnto engagement with
the roller at a locatlon about one o'clock on a roller rotatlng
counterclockwise for separatlon onto opposlte sides of the roller. ~oth
plywood and steel sheathed rollers were employed. Unacceptable results
were obta;ned. A two stage double roller separator was also
constructed and tested on thls basls. Acceptable sortlng was not
ach~e~ed and experlments uslng rollers were abandoned.
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It is noted that in all of the roller experiments, the
material to be sorted lmplnged on the roller ~n a direction generally
normal to the tangent o~ the roller at the lmplngement locat;on.
It ~s also noted that the slld~ng feedlng of the unsorted
mlxture did not provlde unlform veloc1ty of the stones and potatoes,
slnce some tend to ro11 and others tend to sl~de.
Br;-t~sh Patent 4684 of 1909 descr~bes a system for sorting
materials ~n which the mater~als to be separated are caused to be
dr1ven vertlcally downward lnto engagement w~th a rotating roller.
In U.S. Patent 1,692,343, mater~als to be separated are thrown aga;nst
a stretched res~lient fabrlc. U.S. Pa~ent 1,641,492 teaches the use
of a res~llent conveyor from whlch potatoes bounce off for separat~on
thereof. U.S. Patent 2,666,524 employs a reslllent ramp for separation.
French Patents 95,161 and 1,513,792 descrlbe potato
s~rting apparatus wh~ch does not employ a rotating roller.
Separat~on of agricultural produce from spurlous mater1als
by non-mechanical methods is also known, as exemplifled by
U.S. Patent 3,675,769 which describes electronic sorting and
separating apparatus.
According to the present invention there i~ provided
apparatus for separating agricultural produce such as
potatoes from other materials such as clods and stones,
the apparatus comprising:
a ~enerally cylindrical separation roller having a
steel surface; and
mean~ for caus~ng an un~orted mixture of
agricultural produce and other materials to impinge upon
the roller at an ~mpingement location area at a generally
uniform velocity and in a direction which is not normal to
a tangent to the roller surface at the impingemænt
location area, the impingement location area being
sit~ated to one side of the top of the roller surface,
whereby substantially all the feed material is discharged
to the same side of the roller as the impingement location
area, the produce and the other materials being separated
from each other by the difference in their respective
rebound differences from the roller. Such apparatus is
highly efficient and simple to construct and overcomes the
deficiencies of prior art separation apparatus.
B
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Preferably ~he apparatus is provided with me~ns for
producing rotation of the separation roller, most
preferably in such a direction that the impingement
location area has a downward component of motion.
Preferably when using the apparatus of the
inventioll, a single layer of unsorted mixture is supplied
along a conveyor belt into engagement with the separation
roller at a velocity which minimi~es interference between
impinging and ~ouncing materials~ The conveyor is
prefera~ly operative to feed ~he unsorted mixture at a
horizontal speed between 0.2 and OOS meters/sec~
Further in accordance with the present invention
there is provided multiple stage apparatus for separating
agricultural produce such as potatoes from other materials
such as clods and stonesr the apparatus comprising:
a first generally cylindrical separation roller
having a steel surface;
first apparatus for causing an unsorted mixture of
agricultural produce and other materials to impinge upon
the first roller at an impingement location area at a
generally uniform velocity and in a direction which is not
normal to a tangent to the rollsr surface at the
impingement location area so as to separats ~ome of the
agricultural produce from th~ unsorted mixture;
the implngement location area being s~tuated to one
side of the top of the surface of the first roller,
whereby substantially all the partly separated mix ure is
discharged to the same side of the first roller as the
imprin~ement location area, the separated agricultural
produce and the remainer of the unsorted mixture being
separated from each other by the difference in their
respective rebound differences from the roller;
first produce collecting means for collecting
separated agricultural produce located at a first location
relative to the first roller;
remainder conveying means for receiving the
remainder of the unsorted mlxture of agricultural produce
and other materials, which remainder conveying means is
located at a s~cond location relative to the first roller;
a second generally cylindrical separation roller
having a steel surface;
the remainder conveying means being operative to
cause the remainder ~o impinge upon ~he second roller at
an impingement location area;
second produce collecting means for collecting
separated a~ricul~ural produce located at a firs~ location
relative to the second roller; and
refuse collecting means for collecting refuse
separated from the agricultural produce and located at a
second location relative to the second roller for
disposal.
Additionally or alternatively the multiple stage
separation apparatus may provide uniform feeding velocity,
single layer feed and oppositely directed horizontal
components of velocity of impingement and impingement
location area.
The present inv ntion also provides a method of
separa~in~ agricultural produce such as potatoes from
other materlals such as clods and stones, including th~
step of causing an unsorted mixture of agricultural
produce and oth~r mater~al3 to impinge at a generally
uniform velocity upon a generally cylindrical separation
roller hav~ng a steel ~urface, at an implnyement location
area in a direction which is not normal to a tangent to
the roller surface at ~he impinge~ent location area;
the impingement location area being situated to cne
side of the top of he roller surface, whereby
substantially all of the at least partly separated mixture
is discharged to the same side of the roller as the
impingement location area, the separated agricultural
produce and the remainder of the mixture being separated
from each other by the difference in their respective
rebound differences from ~he roller.
BRIEF DESCRIPTION OF THE DRA~INGS
The present invention wlll be more fully understood and
appreclated from the followlng detalled descrlptlon taken in
conjunctlon wlth the draw1ngs ln wh~ch:
.
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~19. 1 is a schematlc lllustration oF separation
apparatus constructed and operatlve In accordance wlth a
preferred embodln1ent of the invent~on;
Figs. 2A and 2B are respectlve top view and side view
illustrations of separation apparatus constructed and operat;ve in
accordance wlth an embodiment of the present inventlon; and
Fig. 3 is a detailed side vlew illustration indicating
a roller cleaning knlfe assembly.
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DETAILED DESCRIPTION OF tHE INVENTION
Reference ls now made to ~lg. 1 which illustrates
ln schematic, diagr~mmatic form~ separation apparatus constructed
and operative in accordance w~th an embod;ment of the present
invention. Th2 separat;on apparatus comprises a feed;ng conveyor
10 which is provided with an eccentrlc roller 12 or other
sultable means for providlng vlbratlon of the conveyor surface
to provlde a slngle layer of an unsorted mlxture of agricultural
produce, such as potatoes, and other undes~red mater;als, such as
stones and clods. The vlbratlon of the surface of feeding conveyor
10 is also operatlve to slFt out loose soll and clods through the
conveyor surface ltself. For this purpose the conveyor surface may
be formed in such a way as to deflne interstlces thereln for
passage therethrough of such loose soll and clods whlch then
fa11 onto a chute 14 and are dlrected away from the agrlcultural
produce for removal.
The carrying surface 16 of conveyor 10 moves generally
in a direction indlcated by an arrow 18 and applies a driving
force to the objects carrled thereon having a component in the
direction indicated by arrow 18. Thls drlvlng force causes the
unsorted mixture to leave th2 forward end 20 of the conveyor
in a predetermined trajectory and to lmpinge withln a generally
predetermined range of dlrect~ons on the surface of a generally
cyllndrical separatlon roller 22. Roller 22 ls typically formed
of 6mm thick steel and is drlven ln rotation ln a counterclockwise
direction indicated by an arrow 24.
~ ~he unsorted materlal tends to lmplnge on roller 22 within
a predetermined g~neral ar2a, hereinafter termed the impingement
locatlon area. It ls a particular feature of the present -inventlon
that the direc'ion of impingement af the unsorted material is not
normal to the tangent to the sur~ace oF roller 22 at the implngement
location area. The additional vector component oF force thus
provided has been found to slgnlflcantly enhance separation
efficlency Preferably, the materlal implnges on roller 22 at an
ang1e of betwe~n 30 - 45 from the horlzontal.
. _
It is a further partlcular feature of the present
-invention that ln contrast to the sllding chutes employed in
the prior art, the feeding conveyor lO supplies the unsorted
mixture for imp;ngement onto the separation roller 22 at
a generally uniform velocity. An addit;onal feature, already
noted, is that a single layer of unsorted mixture is supplied
by the feeding conveyor lO. A further feature, which will
be mentioned further hereinafter, ls that the feeding speed is
withln a range which has been found empirically -in apparatus
having the above mentioned features, to prevent interference
between -implnging materials and materials wh1ch have already
bounced off of the separàt-ion roller 22. these features taken
indiv-idually and 1n comblnat10n enable a high quality of separation
to be provided.
It ls add-itionally noted that in the illustrated
embodiment, the feeding conveyor lO imparts a hor-izontal
veloclty to the unso~ted mixture, ln clear contrast to certain
pr-ior art teachings, such as the aforesa-id Brltish Patent 4684 of
l909. In accordance with a preferred embod-iment of the
present lnvention, as lllustrated, the horlzontal component
of the lmpinging velocity of the unsorted mixture -is oppositely
d-irected to the hor~zontal component of the velocity of the
-impingement locatlon area of the separation roller 22.
Alternatively, the horizontal components may be in the same
directlon.
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The agricultural produce, such as potatoes, rebounds
farther from the roller and ls collected on a conveyo~ belt 30,
while the remainder of the unsorted mlxture falls onto a conveyor
belt 32. S;nce the ;nitlal separat;on stage may not succeed ;n
removin!~ all of the agricultural produce from the unsorted mixture,
conveyor belt 32 ls d;rected to a second separation roller 34,
whose operatlon is similar in all respects to the operation of
roller 22, including pre-ferably; the specification of the
relationship of the ;ncident dlrection of the mixture as being
not normal to the tangent to the roller ;mpingement location
area. The agricultural produce ;s collected on a conveyor
belt 36, while the refuse is collected on a conveyor belt 38.
Reference is now made to Figs. 2A and 2B which together
illustrate separation machlnery constructed and operative in
accordance with a preferred embodiment of the present invention.
For ease of understanding, elements which are shown in F;g. 1 will
be ;dentif;ed by the same reference numerals as appear in F;g. 1.
The apparatus of Figs. 2A and 2B comprises a base 9 onto which
is mounted feeding conveyor 10 and eccentric roller 12. The separation
roller 22 is bearlng mounted onto chassis 9. An electric motor 11
is coupled by means of d drlve belt 13 to feeding conveyor 10 and
rolier 12 for driv;ng thereof ~n coord1nated motion as well as
drlving of a side elevator 15~ whose funct;on will be described - -
hereinafter. According to a preferred embod;ment o~ the ;nvention,
the pos;t;on of the forward end 20 of the Feed;ng conveyor 10 relative
to the roller is such that the ;mpingement location area will be 30-45
from the horizontal on the roller.
Conveyor belt 30 is driven by an ~lectr;c motor 31.
Above belt 30 there extends chute 14 for small diameter refust d;sposal.
Conveyor belt 30 dlscharges in a produce storage locat;on (not shown).
It is noted that feedlng conveyor 10 is preferably a
bar-type conveyor which def;nes interst;ces as described hereinabove
in connection with Fig. 1.
`\
ConYeyor belt 32 may be any suitable type of,conveyor
belt and ls driven by an electric motor 33 via a drive belt 35.
Second separation roller 34 is'also dri~en'by motor 33 via
belt 35. Conveyor belt 36 whlch receives the'agr;cultural produce
from second roller 34 is driven by an electrlc motor 37 and
discharges onto s;de elevator lS, mentioned above. Side eleva-tor
l~, in turn discharges onto belt 30. Refuse conveyor belt 38 is
driven by an electr;c motor 39 and transports the refuse to a
removal location (not shown).
A typical surfa,ce speed for rotat;on of rollers 22 and
24 ;s about 0.6 m1sec. while the'typical feeding speeds of
conveyors lO and'32 are between 0.2 and 0.5 meters/sec.
Reference is now made to F;g. 3 which ;llustrates a
roller clean;ng knife,40 which engages rollers 22 and 34 for
cleaning thereof. It is noted that the knife 40 ;s an elongate
sheet of a suitable metal which is spring biased agalnst the
roller surface and ;n a direction facing the direction of
rotation of the roller surfa,ce, whlch dlrectlon is indicated by
arrow 24. Knife 40 ;s supported on a support bracket 42 which in
turn is pivotably mounted onto a shaft 44 wh;ch is fixed onto
the base 9. A sprlng 46 pro~ides desired spring biasing of the
knife against the roller.
It will be appreciated by persons skilled in the art
that the present ;nvention ;s no-t lim;ted by what has been
particularly shown and described hereinabove. Rather the scope of
the present invention is li~ited only'by the claims which follow:
_g_
