Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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'TA~~.~:~~ ~,~1CL=IpSUI,~Trl~t~ l~A~.l~li~ll~
~:oootl This application claims priority under ~5 LLS.C. ~ $~9(e~ ora f1. s.
Provgsyonal
Application No. 50/490,914 entitled '~r~~L~'~ E~IC~~'S~~~~Il~~ 1VIAC~II, filed
on July 29, 200, by C~leran ~avis and Craig IV1. ~ugteveeri, tine entire
disclosure of
which is incorporated herein icy reference.
~A~:I~CV~1JN~ ~F 'I':~lE II~VE1~T'I'I~I~1
100021 The present inventior3 relates to an encapsulating machine and
particularly to an
improved machine er~ployi~~g a pair of offset die rolls for, in one
embodiment,
encapsulating medicinal tablets w~.~h a plastic fi~rr8 rr~a~~erial, such as
gelatin.
As used herein, the terra °'tablet" refers to a prefe~rrr~ed shape,
such as a round
tablet or an elongated tablet frepuently r eferred to as a caplet. ~Ihen a
medicament,
such tablets are preformed in ,conventional tabletting presses and typically
include
excipients and fillers in additior! to the active ingredients. ~'ncapsulating
such tablets
with plastic films, such as gelai:in, has been well known since the early
1950's, as
disclosed in L1.S. Patent lVo. 2,'~~5,081 showing e~uipn~ent employing two
offset die
rolls, one of which transports tablets positioned on a gelatin film into the
nip between
the die rolls for eracaps~.latio:~ of =he tabiets by a second ~;elat~n. film
on the other of the
die rolls. 1~3 order to adjust the ~~ressure between tiae die rolls for proper
sealing of the
film around the tablets, oz~e of the die roll drive shafts has bearings
mounted in
elongated slots which bearings are urged by a pi~~ and spring mechanism to
provide an
adjustable pressure between the die robs.
ioo04] Although such a system provides a 'oasic adjusto:r~er~t mechanism for
pressure
betv~ieen co-acting dies in a tablet encapsulating ~a~achine, it does not
easily
accommodate for changes due to wear of the die rolls during use of the machine
nor
does it accommodate dynamic lateral adjustabiiity o~ one Lie roll to the
other.
iooos; It~ore current tablet encapsulating machines are disclosed in, for
exa~~ple, 1J.S.
Patent hlo. 6,209,29, which i~acludes direct gear-driven die ~°olls and
tablet feeding
mechanism to synchronize the depositing of tablets on one gelatin film prior
to
introduction into the nip ~oetween two die rolls. Although such a system
provides
clocked and synchronized depositing of tablets onto ~ gelatin film, the use of
direct gear-
driven die rolls and the tablet feeding rrmchanism wiI?, durir,~g use, cause
wear and
backlash betv~~een the numerous gears employed. Such a system is not easily
adjustable
_1_
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to allow resynchronization of the introduction of tablets i~.to the die rolls
upon wear of
the gears.
X000&l l~lso, tablet encapsulating r~,achines employ rolls, k:r~ow~ a.s mangle
rolls to grab
and rerr°~ove the webs of encapsulating film from the die°,
rolls once the encapsulated
tablets have been remove from the films which are, at tvis t;~e, laminated to
one
another. ~n occasion, the mangle rolls become jarnirr~ed with tb.e web
material
necessitating stopping of the e~ai~e r~iachine v~hile the ~aa~~ is cleared.
This leads to
undesirable down time during ~ f,~~~oduction rur~. There e~;ists a need,
therefore, for an
improved web take-up system wlqicl~ is less prone to jarrk.~rr7ing and, if
jammed, c;an be
easily and quickly cleared.
iooo~l further, with existing df° rolls, some difficulties haare beEn
encountered forming
a tight peripheral seal of the g~;latin lal~e on prefo~rn~s as ~~~ell as wear
on the die rolls
during use.
~ooo~l Thus, there remains ~ n~.ed fo~° a tablet encapsuiati:r~.g
o~ac;hine of the type which
deposits tablets on a gelatin fily ia~ advanced of the nip bet:~reen die rolls
having cavities
for encapsulating tablets with plastic lil~n material, such as gelatin, around
the tablets,
and which can accornrr~odate cont:~nued t~se of ~ he machine, including the
wear of the co-
acting dies themselves. There also ~;xists ~ need for an encapsulating
machir°se which
easily acco~nn~odates ad~ustrne~at :for synchronising the clocked positioning
of tablets on
one sheet of plastic film on a die, roller, including precise p;~sitiozzing
with respect to the
tablet die cavity therein arq~ one which efficiently seals thc: preforrn
tablets and
subsequently removes the wel~ m~.terial frorr~ the die, rolls.
S'1J1~~t~~.~ F Tl~~, ll~I~I~NTI:~~
loooGl The system of the present invention accornrnodates these needs by
providing an
adjustable double fulcraim spring pressure between die rolls which replaces
the constant
pressure system of the prior art to compensate for surface var°iations
at the point of
contact between the dies and a~~ ;adjustable offset drive coupling between the
axle of at
least one of the die rolls and the associated drive shay l~t i:o allow for
independent
movement of the die axle to ccrn.pensate for die wear. ~.~ditionally, the
system of the
present invention replaces sewer al direct gear-driven couplings between the
various
drives and tablet feed roll with precise pulley-driven timi~~g 'pelts and
phase adjusters,
which allow greater flexibility i~. sync~~roni~in~; the clocked introduction
of tablets onto a
film on one of the die rolls for subsequent encapsulation at: the co-acting
nip between the
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die rolls. ~ gear coupling e~~p~o,yed between die roll sha9~~~, iracl~~des an
ad~~stable split
gear to accorraodate f~r backl~.slg and gear year. F~rthe~°, An ore
err~b~dirnent, 'she die
cavities for the tablets inchadc ,~. step-cat t~ irr~~~rove the se~.ling of
the films around the
pref~rrned tablets. ~lsc~, in ~nc ~~,n~bodirner~t, a c~.rc~.rr~ferenti~l f~zb
rail is pr~~~~ided ~n
opposite edges of each die to pr~ve~at e~ccssivc v~ear of die cavity lands.
X00101 These and other featnrcs, objects arid advantages of tlae present
invention will
become apparent up~r~ readirg the f~l~aoaving dcscripti~a~ tlzcreof ~ogctr~er
with reference
t~ the accompanying drawings.
I3I~IEF I~~~~~I2IpTI~7l~ ~~~ TL~~ I~T~~~~VIl~1(~S
Fomi_~ dig. 1 is a fr~r~t elevatic~nal view, partly broken a~cray, of an
er~capsnlating
machgine embodying the present i~;ventit~ns;
eool~l pig. 2 is a perspective view, partly broken away, o~° tIo_e
tablet feed rra.echanisrn,
seen also in pig. ~;
lootj3 pig. ~ is an enlarged rragp~aentary plan view of one of the die rolls,
sl;towing the
die cavities therein;
loot~i Fig. 4 is a fragmentary c,°:oss-sectional view of the: rnatir~g
a~pper and lower die
rolls;
100153 pig. ~ is a greatly enlarged cross-sectional view of t~~e die rolls
shown in Fig. 3,
taken along section line ~-~J of Fig. ~;
10oW3 pig. 6 is a greatly enlarged view of the circled area ~I sF~c~rwn in
Fig. 5;
1001'73 pig. 7 is a fragmentard;T plan view of a dis° roll Pursed for a
different shaped
preforrn;
loom3 pig. ~ is a cross-sectional view thr~~gl~~ one of the die cavities shown
in pig. 7,
take~~ along section iir~e ~IIII-~JIiI in pig. 79
loom3 pig. ~ is a rear upper perspective ~rie~a of tl~~e rr~a~chir~e, partly
disassembled to
show coynponents of the drive system;
100203 Fig. 1~ is a vertical cross--,sectional view of the rear of the machine
with the end
plate removed;
loo2y pig. I1 is a vertical cposs-sectional view of tl~e re~c~- of tl~e
machine, taken more
toward the froa~t than pig. ~ t~ ~>h~~w drive belt intercor~nector~s;
100223 Fig. 1~ is an enlarged ar~~ss-sectional viwv of the: machine taken
along section
line III-III of Fig. I;
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~oo~3i Fig. 1~ is a irag~ae~tar~,% enlarged, partly broi~en a~,~ay,
perspective view of tire
upper and lower die roll drive a~-~ec~Iaar~Lisr~s shown in Fig. ~~2;
~oo24.i Fig. 14 is an enlarged f~wagrr~e~.ta:y cross-sectional ~~iew talen
along section line
~I~J-~I~ of Fig. I3;
oo2s i Fig. 15 is an enlarged cross-sectional view talen ,along F~ection line
X~T-~ of
Fig. 13;
Loo2~i Fig. 16 is a fragrr~entary front elevationat view sho~x~ing the split
gear drive for
the upper die roll and the rnatiag drive gear for the lower die role;
loo2~;i Fig. 1 i is a greatly enlarged frag~~entary front elcvational view of
the circled
area ~~III in Fig. 15;
~oo2~i Fig. 1~ is a greatly v~~~a~°ged fragrr~enrary vertical cross-
sectional view of the
upper die roll spring adj~strnent mechanism, showrvalso in a~ig. 12;
~oo29i Fig. 19 is a perspective ~~i~:w of tl~e z~aangle roil ass~:r~qb~y,
shown also let F ig. 1;
~oo3oi F ig. 20 is a froa~t elevaiional view, partly in phan~~~form, of tl~e
a~~gle roll
assembly shown in F'ig. 19;
ioo311 Fig. 21 is a top plan ~~ie~v of tl~e mangle roll asseml~i~r stzc~wn in
Figs. :~~ and 20;
and
ioo3zi Fig. 22 is an enlarged perspective view of an encap;s~lated caplet made
with the
rnact~e of the present iavencica~v.
I~~'fI~IL,~I~ I~E~~I~IF'fl~I~ ~F TI~I~, PI2EF'EI2R.F,I~ ~~~~t~hII~EI~'~f
1oo33i Referring initially to F:ig. t, a brief description of the preforr~a
tablet
encapsulating machine IO emb~~dying tI°~e present invention is
f~~°st presented, followed
by a detailed description of t~~e components. I~iachine i0 r~:ceives preforms
(i.e.,
compacted tablets) ir°~ the for~~x of round or caplet-shaped
indiFaidual tablets ~ 2 Fig. 2),
which are supplied fr~r~n a l~opp~er 14 into a tray 22 of tablet-feeding
assembly 20 (shown
in detail in F'ig. 2). 'tablets it~~~~ tl~e tablet-feeding ass~e~nbly, which
is descried in
greater detail below, are apptied to a first gelatin web or frlrrc 3rd cast by
a first casting
drum assembly 32 which recei~,~e;~ heated liquid gelatin fio~~ a ~~pply 3~
and. applies it
to the casting drum with a spreader boy blade 3S. ~'he first gelatin fitna is
taken from
casting dram assembly 32 by a tale-off roller 3~, are s~vler roller 40 which
applies
mineral oil to the surface of tlac film 30 which contacts th:e bower die role
50. ~ lie film
also passes over an idler roper 4:~. "fablets 12 frog: the ta~lez-feeding
assembly 20 are
deposited i~~ rows onto an inde:~ oil 43 (Figs. 1 and 2), ~~Jhicl?g transfers
the pre-formed
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tablets onto the gelatin film 3~ ~a a location on lower die roll ~~d
G~ppro~irr~ately ~0° from
(i. ~. , npstrean~ ofd the nip ~5 vr~~ich is the junction betweea~ the lower
die roll .5C and the
upper die roll 6(1.
ioo341 ~ second gelatin film '~f~ i,9 for~~ed ors a second casting drG.~rr~
assembly 44 frorr~ a
supply of liquid gelatin by a seco~~d spreader blade 4~. ~'f~e second film 7Q
is removed
from casting drum 4~ by take-off roller 4~, idler roller 4'~., ane~ ak~ oiler
roller 4S, which
applies n~iz~eral oil to the surface of gelatin file '7~ ~,vhich engages the
surface of upper
die roll 60. '~'he die rolls ro~wate in opposite; directions, with the lower
die roll 50
rotating in a counterclockwis~~ dir.°ection, as seen in hig. 1'~,
~vllile the upper die roll ~Q
rotates in a clockwise direction to encapsulate the pre:~orrns 1 ~ beaweenb
the gelatin fil~rss
30 and 7f1.
ioo351 ~'he encapsulated prefo~°vns 1 ~~ ~sho~vrl in ~'ig. 2~,;) fall
f~°orr~ the vveb of gelatin
films onto a collection belt g'~ from the die roll area asst to a discharge
conveyor S4 for
subse~ue:~t collection and dry ir~g. 'I':l~e web of gelatin films 3C1, '~~
travels through a
chute asseaxibly ~~, which incla.des hex rollers to Tree any remaining
encapsulated
preforrrss from the rveb. 'T''ae cl.~~te asse~bl~r ~1~ is co~~~~r~ercially
available and well
known ire the art. 'the now lar~ri~~ated ~,veb of iilrns 3~ and '~~ travels
through the chute
asserrfbly 8~ into a mangle roll assembly 4OO, descr~~ed below i~ corrriection
with pigs.
19-21, which draws the web from the machine for coi.lectior~ and recycling.
ioo361 ~r~ addition to these basic components, the casting dr~~rn assemblies
3~, and ~4
conventionally include cooli~~g air daacts 3i arid ~~:, as we;l-~ as liquid
cooling jackets to
provide the gelatin films 3C1 and 'fig ~,vith the desired degree of plasticity
for use on the
die rolls for encapsulating pR-ef~~rn~s. '~'~~e gelatin film is <~.
co:nvc:ntional composition of
gelatin and plastici~er, such as glycerin, and films 3fl, 7l~ can have
differing
characteristics, such as diffeY:~a~:~ colors for providing product
identification for a
particular preforrn tablet beir~.~> encapsulated. ~Iedican~e~~ts, such as
analgesics and
analgesics combined with other cornrnon active ingredient;>, are typical
prefor~r~s. Such
tablets are frequently anufact~~red at a site other than the location of the
encapsulating
machine and are positioned in l~ol>per ~~. for feeding the ~achir~e ltl. ~'he
preforans exit
the hopper g4 and are transpor~.ec~ by pan l~ into tray ~~, wl-~ich has a
floor ~4 with a
plurality of loragitudinaily extending grooves 2~, as seen i~a i~ig. ~. ~'he
tablets generally
are aligned longitudinally and vertically on their edge ~rithin parallel
longitudinally
extending grooves 25 in the floo~~ ~~ of tray 2~. ploor ~;~ ~.s inclined at ao
a~-~gle of
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approximately 45°, as best see~~; iz~ Fig. 1, and includes ~
~~isc:harge end 26 i~~cludir~g a
brus~~ 2~ which rotates in a c~~nterclp~ck~,vise :~irecti~n, as seen by
arr~~~a ~ in Fig. 2,
and is driven by rrrotor 29 to br~zsl~ away preiorrns ~~gich a:re Trot ~c~
aligned.
~oo37i The preforrrrs slide by gravity dowry trey 22 arrd a:re: discl~aroed
from end 26 of
the tray into a helm 33. Helix 33 is a chute that rotates t~.m pr~ef~rrr~s
90° t~ place the~°n
in a covered, do ~,wvardly depending chute 35 in r~pe~r alignrrrent f~r
transfer ~nt~
index roll 49. Index roll 49 ir~ciudes a drive pulley 51 (;p'ig. 1) which is
driven by a
double-sided drive belt 52 extending around a rrrain drive p~~l:le.y 54 and a
pair ~f idler
rollers 56 and 5~. lain drive pulley 54 is driven by a shift 59 extending
fr~rn a belt-
driven pulley as described bei.~~;z~.
ioo3~l The tablet-feeding asse:~nbly 20 also ir~c~~zdes a pin snap block 21
which is
positioned near the discharge end of chute 35, which pr~w~idsrs rrrovable
blacking pins
exte~~ding through chute 35 c~ step the flow of pref~~°ms ~:hrr~ugh
ci~ute 35 onto index
r oll 49 vahen a pref~rrr~ shape ch~~ngecver is being rr~ade ~~e. ~. , it~rr~
a caplet t~ a r~und
tablet), which necessitates the crranging of die rolls 50 and f~0 as well as
the tablet-
feeding asserrrbly 20 acrd index roll 49. G~~nvenier~tly, t:f~e tablet-feeding
apparatus is
mounted by a quick disconnect thzeaded handle 3 a ~~ig. s,) to a plate 1.34 of
the feeder
while the index roll 49 is also quickly asserrrbled to piste 134 by the use of
quick
disconnect threaded handles 43, as seen in pigs. 1 and 2. ';i'he index roll
drive shaft 59
is precisely timed with tire die <~11 drive rrjechanisrrr t~ assure that the
preforrrrs 12 are
synchronously positioned orr the gelatin filrrr 3G~ cc~ verdng the i~~v~c~r
die roll 50 in precise
alignrrrent with tire rrrold cavities i00 of the die rolls by tire drive
raechanisrrr
subsequently described. 1rz piece of the gravity fed tablet-feeding assembiy
20, a
commercially available pIartrrett tablet feeding apparatuu,
r~anui°actured by l~. ~1.
lEIartnett company, can be errrpioyed to transfer° preforms frorrr
hopper 14 onto the index
roll 49 and subsequently onto tire gelatin filrrr 30.
ioo3gl Faclr of die rolls 50 and ~0 include, deperrdirwg upr>:~ tire ;jhape of
tl°~e preforrrred
tablets, frorrr about 39 to about ~~4 rows of mold cavities 100 ~lFig. 3),
with each row
including frorrr °~ to ~ mold cavities, again depending u~~orr tire
preforrrr shape being
encapsulated. Fig. 3 is an ei~l~rra~,ed fragrrrentary view of ~. section ox
die roll 50 with
mold cavities 100 for receiving caplet-shaped tablets. l~acl~~ of the die
rolls 50, ~0
include a die surface 105 which is recessed frorrr the land, 10°~
surrounding each of the
die cavities 100. The lands having a height above surface 10S of from about
0.015
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inches to about 0.063 inches,; ~:~hich varies as the dies a~.°e; used
arad resurfaced. 'phe
land 107; as shown in Fig. 3, ckrc:urnscribes a i;eneral caple~. shape, and
the (boor 103 of
each die cavity 100 includes an aperture 108, which co~nr~~:~rsicat°s
with a ~ga~ifold 109
Fig. 4), which can lead to a °.~acuu~n source or otherwi;9e exhaust air
from the mold
cavities during the encapsulation process. Each o~ the die ~~olls ~0, 60 also
include
circurnferentially extending r~~b rails 102, 104. positioned ~iea~° the
outer edges of the die
rolls to span opposite sides of the rows of mold cavities :a00. fails 102, 10~-
extend
upwardly frorr~ the surface 10~ o:~ the respective dies substantial~iy the
sage distance as
wands 107 to provide additional wear surfaces for the co-acting dies as seen
ire Fig. ~.,
where the mating rub rails 102 a~xd 10~- on each side, respectively, engage
ore another
as do the mating lands 10'7 of eacr~ die cavity 100.
~o~~i In order to improve she peripheral seal 113 around the ~:ncapsulated
talalet 112
Fig. 22), the =inner edge Vii, e. , 4°ac:i~g edges) of each of th~~
iar~ds 107 includes a step-c~it
110, as best seen in Fig. 6. ~'he o~~old cavities for the caplets, as seen in
Fig. 3, include
such a step-cut around the opposite ends. T::ae ends of tee cas~let, which are
tightly
curved, have in the past beer~A somewhat problematical wit'.1~ respect to
forming a perfect
seal of the two gelatin filrr~s. ;y providing a step-cut 110 i~~. the areas of
the curved
sectioa~ of mold cavities 100, the gelatin or other films are pinched together
before the
cutting edge 111 of the die rol-cats the film material. For s~zch purpose, the
step-c~tt
1 i0 has a deptY~ d, of about ~~.00'7 inches a~~.d a lateral dirr~ensio~~. l,
of about 0.010
inches. ~enerarly, the step ctzt 110 will have a depth ~~f about 6~ % of the
initial
thickness of this gelatin film. c~ov the .Oll film employed in one embodiment,
d, was
0.00'? inches. ~s seen ir~z Fig. ~; the step-cut 110 at eac.h~ end
circumscribes or~Iy the
curved end portions with the st:~aiglat sides of eac~~ of tape mold ca vibes
100 being
slightly chamfered. mold cavitp 100 is of sufficient size aog.l shape to
accom~r~odate half
of each of the caplets placed therein during the er~capsula~:i~n process at
the dic: nip, as
illustrated in Fig. 4., without crusl4ing dhe prefor med core.
ioo4t i Then encapsulating oth~:r shapes such as small o~~~long tablets or
round tablets,
similar dies, such as upper die ~0' Figs. '7 and. 8), are employed with die
cavities 100'.
'~Iith the rounder die cavities 1~~0' shown in Fig. e, a row ~~f onl;y '~
cavities i;~ possible,
however, for small preforrr~s, S~. sucrx rows can i7e ac;co~an~aodated on the
12-inch
dian~geter die roils. Similarly, if larger round tablets are lseing
encapsulated, frequently
only 48 rows can be accomrr~odat~°d. lie 50' and its matia~g upper die
knot shown) also
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.nclude rub rails 102' and I04'. The individual die cavities I00' include
sands IO?'
with step-cuts 110', as seerw ire Fig. ~, e~ter~ding arour°~d the
entire periphery of the
curved die cavity. 'kith the step-cut 110 ° for rouncl~. table-=a ,
iypicaily the depth of the
step-cut d, ' will be 0.00 inches, while the lateral dirr~er~sio~~ It ' will
be ab out 0.006
inches, somewhat less than for the lateral cut in the caplet die cavity 100
sho~~n ire Figs.
3 and ~.
10042; The I2-inch diameter die roils ~0, 60 are rotated. at a speed of from
about 2
~PIi~ to about 5.~ Fl~. ~'itlr caplets haraing ~ die cavities in each of 39
rows, 312
caplets are formed fo1° each. re~oiution, such that at ~:he
pr°~:ferred speed of ~. ~F, for
exarr~ple, 12~~ caplet preforn ps per rrr,ir~ute are encapsulated. The die
rolls typically are
rrnadc of alumiraun~, which have Teflon°-bonded hard anodized surfaces
hardened to a
~oclcwell ~ hardness of 60 ~:o provide ~~nproved wear characteristics for the
die rolls.
The throughput at 4 FPM speed for small tablets which have ~4 rows of ~ die
cavities is
approximately I:~ 12 tablets per minute, while h~'or the larger tablets, which
have ~-~ rows
of 7 die cavities, is approxirr°aately I344 tablets per minute.
ioo431 I~fachine 10 includes a lfarnework, in~;Iuding vertz~~ally extending,
hor~ontally
spaced walls ? 30, I40, and 150, ~;xtending up~.rardly froar~ ~~aoor l-60
Figs. 9-1I~. Floor
160 ray be supported o~~ a sF:and having suitable legs (not show in Fig. I~.
The
vertical walls are supported by e~reral cross partitions, in~;luding
partitions such as 161-
163, at suitable locations to provide structural rg~~gty to the framework
defined for
supporting the various drive co~~apo~m~ts shown ire Fig=.. 9-.ll. mounted in
spaced
relationship to the front wall 130 of machine 10 is a vertically extending
outside die roll
mounting plate 170 Figs. 1 and 12~ secured at its upper end to plate I'~2
extending from
wall 130 and at its lower end to plate I7~-, also extendiaig frorr~ wall 130,
~:o position
plate 170 in spaced relatior1s13iIto the outside of wall 130 vo rccc.eive and
support upper
and lower die rolls 60 and 50, respectively.
[004-1 falls 130 and 150 include suitable apertures forty rcceivirgg the
bearings for
supportirpg drive shafts I1~ and II7 Figs. 9-L1; for gclatirr film-forming
drugs 32 and
44, respectively. ~s 'pest seep i~ Fig. 12, walls 130% 140, arid 150, as well
as rear end
plate 1~~, include apertures rec:°iviug beari~~gs 1~~ for the a xie 124
of the lower die roll
50. Mall 130 irEcludes an elongavted slotted ap6rrture 132 ~1:~"ig. 9for
receiving a sliding
plate L92 having a bearing 1~9 LFig. I2~ which is aligned with a ~chrnidt
offset coupling
180 and phase adjusting hub 1~2 for coupling to tree axle I2~ Fig. 12) of
upper die roll
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60. plate 170 includes a sirni~a~°ly conf-igured elongated slotted;
aperture 1~3 (Fig. 1)
aligned with slotted aperture I3' in wall 130 for receivi~~g sleding plate 190
with a
bearing 19'~ (Fig. 12;, such tl~~t the upper die roll 60 cap be adjustable
mounted by
means of a pair of spring-loasi~:d sliding plates I90 and 192 (Figs. I, 12,
and 18) for
adjust~8ent toward and away fr o~rn the lower die roll 50 lay utilization of
the fulcrum
:spring mounting assembly 20~~, shown in Figs. I, 12, ar~4d 18. This allows
the
adjustment and lateral co~xtrol cr the upper die roll 60 wit: respect to the
lower die roll
50 to accommodate for die wea.:, gelatin thickr.~ess, and p~°~ctects
the dies against damage
due to a misaligned preform by allowing movement of tl~g~u spring-Loaded upper
die roll
60 in such an event.
ioo4sl Aiding plates 190 and -i92, as best seen in Figs. 1, :i2, and 18, are
generally
rectangular and slide within apcrt»res 1'~3 and 132, respectively. Each plate
i~xcludes an
Tapwardly extending narrowed extensions 191 and 193 (respectively) Ixa sing
upper
surfaces 194 and 19S (Figs. I , 12 a~xd 18) which engage the lower surface 201
of a
fulcrum spring assembly 200 (Figs. 1, 12, and 18) extending between extensions
I91
and 193 and the tips 211 (F~g. I8) o~ a pair oI° adj~;~trnent
scr°ews 212 and 214.
I~djustment screws are received in threaded apertures in upper ends of plate
170 and
wall 130 in alignment with the ~xarrowed slots 1'75 and 133 ~~eceiving
extensio~xs 19I and
I93 (Figs. 1 and 18) of sliding axle-receiving plates 190 and 192. Sliding
plates 190
and 192 are captively held with~.n slots 173 and 132 by suitable gv.~ide
plates I ;r6 (Fig. 1)
and gibbs (not shown) which lxold the slide plates in lateral sliding
relationship to plate
170 and wall 130.
10041 spring assembly 200 includes, as best seen in Fig. 18, a generally
trapezoidal
spring steel menxber 202, wrt~b a pair o~ spaced-apart »aised
serr~icylindrical center
extensions 203 and 204 which engage stacked fiat leaf springs 213, 215, 2I6,
and 21'~ of
differing thicknesses of spring steel for adjustability, as. shown in Fig. 18.
Spring
member 202 is employed as the top spring with the semicylindrical sections 203
and 204
providing a double fulcrum c~noection to flat leaf springs 21_i, 215, 216, and
217,
which rest upon the top surface ,! 94 of extension 191 of plate 190 or 195 of
extension
I93 of plate 192, as best see i.u Fig. 18. ,adjustment screws 212 and 214
extend
through threaded apertures in outer wall 170 and wall 130 and can be adjusted
to
provide a compressive force thr~u:gh spring 202 and leaf spings ;~ 13, 215,
216, and 2I7
CA 02475765 2004-07-27
to die roll 60 to adjust the press~~re bet~.vcen die roll 60 an~I die: roll 50
to approxirsaately
1,200 pound force during e~~cap~>ulatio~y of a pre:forrn.
~004~1 spring steel plates 213, 215, 216, and 217 can have a thickness ranging
from
1/16" to 3,~8" and are stacked a4. siesirecl to provide the ams~unr of force
adjustment for a
given translation of slides l9Ca and 192 within their respective slots ~ l3
any 132,
respectively. Adjustment of the screws 212, 21~. provides a very fine
incremental
adjustment of the pressure bet~~~een the die rolls. 13y providing pivoted
connections of
spring 2C2 with contacts 203 ark 204 to leaf springs 213, 21~, 216, and 217
and to
sliding plates 190 and 192 to which tine axle 126 of die roll 60 is mounted,
die roll 60
can accommodate unevenness and wear between the die rolls and remain in
substantially
uniform contact across the widtof both die rolls 60 and :~0 dorr:ng operation.
~~.zitable
strain gauges and associated readorit displa~~s knot shown j allow an operator
to monitor
and control the pressure between die rolls 50, 60.
sl The spring assembly 200 includes a pin 220 which slidably extends through
an
aperture 221 in plate 172 and ioclucles a slip washer 223 tlmreon. pin 2.20
extends
loosely downwardly through an aperture 224 in spring 202 and apertures through
springs 213, 215, 216, and 21'~ a~~d is capti~lely held in place with a second
slip washer
22~. pin 220 serves to captively mold the spring 202 and 1',eaf springs in
place in the slot
173 in plate 170 and corresponding slot 132 in wall 130.
[00491 The sliding plate 190 includes a bearing-receiving aperture 196 (Fig.
18) for
receiving a bearing 197 for die roll 60 axle 126 supportii~~g ~:lae axle
within the sliding
plate 190 at the outer end of machine 10. The opposite encl o!v a:~le 126
exter~.ds through
bearing 198 (pig. 18) in sliding plate 192 and is coupled by a pl:~ase
adjustment hub 182
to t:~e Schmidt offset coupling 130, in turn, couple: to the; rraai~ drive
shaft 18~ of Che
machine. The offset coupling 180 allows the upper die roll 60 and axle 12 6 to
move
along the direction of slots 132 and 173 toward and away fror3 lower die roll
50 and yet
remain coupled to the main dr ive shaft 184 which need ~~ot be coaxially
aligned with
axle 126. The phase adjustia~.g hub 182 ailo~avs die roll ~0 t;o ~e rotatably
adj~.sted to
provide precise alignment of the respective die cavities 100 (Figs. 3 and 4)
in die rolls
50 and 60, such that a preforro. 12 deposited over a cavity in die roll 50 is
precisely
aligned at the nip 5~ with the corresponding cavity in die r~~ll 60.
oI For purposes of rerrzovi.ng the o~aer plate 170 of tl-~e die roll assembly
section of
machine 10, upper and lower pairs of jack screws 230 and 232 (Fig. 1) are
provided at
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the upper and Lower ends of outer plate I70 to assist whery the threaded
fasteners 2~ I
securing plate 170 to the upper cross plate 172 and lower ~.~°oss plate
I74 are removed.
~ threaded locking knob I9~ Fig. L8) holds each of the die rolls 50, 60 onto
their
respective axles 124, I26 and aalows removal of the die rolls. once loosened,
plate I70
can be urged away from the axle I26 of die roll 60 and axle I2.4 of die roll
50 for access
to replace the die rolls in the event replacement becomes ~~ecessary due to
wear or if a
different preformed shape is being employed for a particula~°
encapsulating run.
(0051 ~'he drive rr~eclzanisn~ for controlling the gelatin-fr~rg~in~; drums 32
and 44, the
die rolls 50 and 60, and associated take-off rolls, idler rs~lls, z~nd oiler
rolls, together
with the index roll 49 is controlled by use of timing belt c~~rives together
with the phase
adjustment couplings, such as hub 182 Fig. 18), and a second phase adjustment
coupling 279 ;Fig. ~) for the tab'!et-feeding n~aechanisrn, as described
below. 'plae tuning
belt drive system is best illustrated in Figs. 9-12. Tl~c~ =nain drive for
machine IO
comprises an electric motor 24C, which has an output shaft co~aplecl to a gear
box 242
secured to the floor 160 of mack°xine 10, as illustrated in Figs. ~3
arid 10. ~'he gear box
includes an output drive shaft 144 (Figs. 10 and I @) coupled tcj a belt drive
pa~iley 146
(Fig. Il) to a main drive belt 250. Fach of the various drive belts shown
co=reprises a
herringbone tooth belt, wl~icl~a is a commercially available lragle pI~ type
belt froru
Caooclyear 'fire & dubber ~ornpany. 'phe belt drive pulleys am engaged by each
of the
drive belts and include a si~raiar herringbone tooth-pattern to mesh with the
ti~r~ing drive
belts to assure precise coupling and timing of the various c;orr~ponents
synchronized by
the tuning belts.
[0052; give belt 250 engages the main drive shaft 184 x~~rough belt drive
pulley 18S
(Fig. II) and adjustable idler pulleys 186. shaft 184 e~:~.ends through a
bearing I87 in
wall 150 and to similar bearin;~s 188 in walls 1.40 and 1 SS (Fig. 12).
tJffset coupling
I80 is secured to the end oi~ drive shaft 184 using a conventional slot and
key coupling
and, in turn, is conventionally coupled to the phase adjust~~nent hub I82.
7~he outer wall
or end plate 1S5 Fig. 9) is secured to wall 150 by str~xts 1S6 and includes
bearings 157
for supporting the ends of the various drive shafts including shafts 184 and
124..
L00s31 'I'he rr~ain drive shaft 184, which extends througl°~ ~rall;9
140 and 150 as best seen
in Fig. 12, into a gear box defined 'oy the space between walls 140 and ISO
and a
partition floor 162 therebet~reen. ~'he gear box so defined includes a
lubricating oiI
which covers the lower section of gear 360 v~Jhich drives shaft 124. Mounted
in the
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space between walls 140 and 1 °i0 is a split gear 300 which
a°r.~gages the drive gear 360
secured to lower die roll drive shaft 124. The split gear, sometimes referred
t~ as an
anti-backlash gear, is shown in detail in 1~igs. 13-1'~ and c:omp~-ises a pair
of gears 310
and 320 positioned in facing contacting radial adjustable relationship. each
of the gears
include a plurality of spokes 311. The purpose of split gear 300 when meshing
with
gear 360 is to provide a srnootlinterconnection between the two gears
regardaess of
gear vaeaa°, such that dies S~J, b0 are rotated in a synchronous manner
Vvith respect to one
another .
(~oS41 The adjustment rriechanism fo< adjusting split gear 300, vincluding
gear 310 with
respect to gear 320, compri~e~ cfn L-shaped adjustment bracket 330 (Figs. 13,
14, and
16). bracket 330 includes fo~~ar locking screws 332 extending through
clearance
apertures in the elongated leg 33~. of L-shaped bracket 3 30 and threaded into
one of the
spokes 312' of the front gear 310 (as seen in Fig. 13). ~'he shorter leg 336
of bracket
330 extends between edges 337 of gear 3I0 and 320 of gear spoke 312 of gear
320, as
best seen in Fig. 14. An adjustable set screw 339 is threaded through threaded
aperture
340 in leg 336 and engages surface 338 for rotating gear 320 ~:vith respect to
gear 310,
such that the teeth 314 of gea310 ca~~ adjusvably overlap the teeth 324 of
gear 320, as
best seen in the enlarged view o:~ Fig. 17.
~oo~sl A plurality of elongated slots 326 is provided in the spokes 312 of
gear 310 and
include a floor 327 for receiving the head of a locking cap screw 328, which
extends
through slotted aperture 326 and the mating aperi~re 3:~9 in floor 32'~ into a
~~hreaded
aperture 342 in each of spokes 312 of gear 320. Fach of the six cap screws 328
are
loosened prior to the adjust~r~ent of adjustment screw '339, and screw 33g is
tightened
until the desired effective width of gear teeth 31~~ and 324- is reached.
After which,
locking cap screws 328 are all tightened to securely fix gear 310 to gear 320
forming a
close connection between ~~he effective teeth formed by gear teeth 314 and.
324 of gears
310 and 320 with the corresponding slots 362 between gear teeth 364 of mating
gear 360
(Fig. 1?). The effective widtlx of gear teeth 31~~ and 32,i~, equal to the
width W of the
substantially identical wid4l~ gears plus the overlap dista~~ce ~'~~, which
can be adjusted
from 0 to about .010 inches axed typically about .OOS irmhes daring use of the
machine.
Gears 300 and 360 in one erx~L}odiment had a diameter oi~ about 10 inches and
effect the
counter rotation of die rolls SO and 60.
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~oos~i ~'he main drive shaft 3 84 also receives, as seen in Fig. 10, ~ drive
pulley 252
which is coupled to a drive belt 254 extending to drive pulley 24'~ on drive
shaft 248 of
oiler roller 48 for casting dray 44, as seen in Fig. 1. An adjustable idler
roller 249
maintains tension on belt 254. Shaft 248 also incl~zdes a dt°ive pulley
256 (Fig. II)
~Jhich engages a drive pulley f~~r a drive belt 2,58 which drives pulley 262
for the take-
off roller drive shaft 245 which drives take-off roller 45 shown in Fig. 1. An
adjustable
idler pulley 2S5 maintains constant tension on drive belt 258.
~oos71 'fhe main drive shaft 184, as seen in Fig. 11, also uncla~des a drive
pulley 264 for
receiving a drive belt 265 which is coupled ~:o the casting drudr ive pulley
266 for
drive shaft 115 of casting dr°r,rr~ 32. Adjustable idler pulleys 26~
and 269 rrraintain
constant tension on belt 265. <~aFn drive shaft 184, as noted above, is gear
coupled by
the split gear 300 and mating gear 360 to drive shaft 124. Shaft 124 includes,
as seen in
Fig. 10, a drive pt~iley 268 which includes a drive belt 2 i2 for the oiler
drive sl~.aft 274
for oiler roller 40, sho~7n in Fig. i. An adj~zs~:able pulley 275 maintains
constant tension
on belt 272 (Fig. 10). Shaft 124 also includes a drive pulley 2~fi, as seen in
Fig. II, for
receiving drive belt 278 which. extends around casting dram 44 drive pulley
282 for the
casting drum drive shaft I1°~. Adjustable idler pulleys 283 and 285
maintains a constant
tension on drive belt 2 i 8. Shaft 124 also includes a drive Irulley 284 (Fig.
1 I) for
receiving drive belt 286 for the index roll drive shaft 288, ~~rith the
tension ova belt 286
being maintained constant by adjustable idler pulleys 289 end 291.
~oo58i 3~rive belt 272, seen in Fig. I0, also drives the take-off drive belt
292 for take-
off roller 38 (Fig. i) by the use of a drive pulley 294 orl shaft 274. Felt
292 engages a
drive pulley 296 on drive shay 298 for the take-off drive roller 38. An
adjustable idler
pulley 297 maintains constant tension on belt 292. fihus, the main drive belt
250 drives
main drive shaft 184, which is coupled to secondary drive shaft 124 through
the split
gear 300 and mating gear 360 while drive shaft 124 and shaft 184 are coupled
by
sy r2chronized drive belts to cacti of the take-off and oile~4 rollers, as
well as the casting
drums .
~0059_~ As noted above, drive shaft I24 drives the index roll 49 drive shaft
288 through
belt 286 (Fig. 11). Shaft 288 extends through wall 130, as best seen in Fig.
9, and into
phase adjustrrrent coupling 2'79 to a drive belt 302 'by r~~eans of a drive
pulley 304 orr
shaft 288. Shaft 288 is supported by bearings 293 ;=.~~d 295 in walls I30 and
I50,
respectively, as seen in Fig. 9. Felt 302 drives through pulley 306 the drive
shaft 59 for
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the index roll drive gear 54 shown in Fig. 1. An adjustable idler pulley 307
ar~aintains
constant tension on belt 302. T b',~s, the index roll 49 driv a is also
synchronized with
both the shafts 124 and 184 i~r the die rolls with the tirr~ing drive belt and
pulley
connections and further synchronized with the use of phase adjusters 279 and
182. This
allows precise alignment of preforn~s 12 from the index roll 4~~ onto the
gelatin film 30
in alignment with the die caviti~s 100 in lo~,~~er die roll 50 and the
subseduent alignment
of mating mold cavities 100 in die roil ~C for the encaps~zlation of
preforr~~s. ~'.fter the
gelatin films 30 and 70 exit tf~e die rolls SO and 60, they pass through the
discharge
chute assembly 80 and into the mangle roll ass~:mbly 400 w~~ich is now
described.
Ioo6ol Mangle roll assembly 4~~t1 is shown in detail in Figs. 19-21. and is
mounted below
the die rolls 50, 60 and chute assembly 80, as seeg~ in Fig. l, to receive the
pairs of
films 30, 70, which have been larr~inated into a web, once the encapsulated
tablets have
been removed from the web. i he mangle roll asserxably 400 comprises a pair of
elongated rollers 410 and 420 rotatably mounted v~Tith r~°spect to an
inverted r7-shaped
frame 430 at one end. Roller 41.C is rotatably rr~ounted to a I7-shaped frame
415 (Fig.
21~, which is slidably mounted at one end in a slot 437 in fianle 430 and a
slot 438 in
facing end plate 439 coupled to frame member 430 by :toss strut 431. 'This
allows
roller 410 to rrlove toward anti away from roller 42c~ in a d~rect~on
lndlCated by arrow X
in Figs. 19 and 21. Suitable bearings couple an axle 41.2 for roller 410 to
the lateral
legs 416 of tl-shaped sub-fram~° 415. ~.xle 412 extends through member
43C. drive
gear 414 aneshes with a drive gear 424 on axle 422 associated with mangle
roller 420.
Frame 430 includes a pair ov mounting slots 432 and ~~34 (Fig. 20) for
mounting the
n~.angle roll assembly to the frc>nt wall 130 of a~nachine 10. ~. drive gear
440 (Fig. 20)
engages gear 424 and is driv~;n by a shaft 442 extending into the a~nachine 10
and
coupled to an adjustable speed drive motor (not shown mounted to wall 130 for
counter
rotating rollers 410 and 420 at a speed to take up the web frorra the tablet
discharge
chute 80 (Fig. 1 ).
~OO~11 The mangle rollers 4i0 and 420 each include meshing linear, elongated
teeth 411
and 421, respectively, which, a.s best seen in Fig. 20, engage one another to
receive a
web (represented by arrojw ~ in Figs. 1 and 20) therebetween. The driven
rollers,
therefore, draw the web dowj~wardly bet~.veen the t~~m roll.ers 410, 420,
which are
partially covered by protective guard 450 (mounted to partially cover r~oiler
420, as
shown in Fig. 25~ and 4S2 (which partially covers roller 410. Canard 4S0 is
mounted to
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CA 02475765 2004-07-27
eross strut 435, coupling an end. plate 436, and frame 430 which supports axle
422 of
roller 420 with a bearing 423. Cluard 4~2 is secured to plat: 4~2.
X00621 holler 420 is mounted ~n rotatable relationship to frarr~e 430 but is
otherwise
stationery with respect to the frame. Roller 410, however, Xs slidably mounted
by frame
41~ within slots 437 and 438 as noted above, such tfaat it i;~ allowed to move
toward and
away from roller 420 in t~~~e direction indicated by arrow ~ an Figs. 19 and
21 to
accommodate movements in the web or an occasional tablet which has not been
freed
froxxa the web as it exits discha~°ge chute 80. '~ h.e movabte ~~J-
shaped frarrze 415, shown
partly in phantom form in Fig. 21, includes a moveable cross plate 462 with
t:he roller
bearings for shaft 412 being mounted to the legs 41.6 extending from opposite
ends of
cross plate 462. P-tate 462 is coupled to a s~aaft 4 70 which extends through
a bushing
472 in cross strut 431 exter~dzx°~g between frame member ~-3Q axed end
plate 439. Shaft
470 is threadably fixed at one e,nd to cross plate 462 and o:~gages a cam-
operated handle
480 which includes ramming surfaces 482 pivotally xr~oux=.ted b;y axle 484
thereto, such
that handle 480 can be pivoted from the closed position, as shown in Figs. 19
and 21,
rotating in a direction indicated by arrouT ~ in Fig. 20 xo urge roller 410 to
the left, as
shown in Figs. 19 and 21, to disengage roller 410 from roller 420 to clear any
3ams that
may inadvertently occur. ~ dditionally, ~ pair of compression springs 4901 and
492
extend over guide pins 491 and 493 with ends captively held icy W readed
apertures 495
and 497 in cross plate 462 Fig. 21~ to urge roller 410 into engagen~er~t with
roller 420
when handle 480 is in a closed position, as villustrated i'n Figs. 19-21.
'This provides a
constant contact pressure between rollers 41U and x.20 d~~riaag normal
operation.
100631 ~4s seen in the drawings and described above, the various driven
eleer~~ts of the
machine are alI interconnec~:ed through timing drive belts and belt drive
pulleys to
synchronize the casting of gelatin film, the depositing of prc:forms precisely
onto the
gelatin film 30 on die roll 60 and the rr~eshing of tl~e die rolls 50, 60 in
precise
alignment for encapsula~:ing tl~e preforms. ~y providi~~g tuning belts and
associated
drive pulleys which operate at a relativel~yl slow speed and by the use of the
phase
adjustment hubs 279 and 18Land split gear 3~0 and by the selection of the
diameters of
the various drive pulleys, the xxaotion of tile casting drums 32 and 44 for
the gelatin film,
the die rolls ~0 and 60 and tlxe index roll 49 are precisely controlled and
synchronized to
assure maximum output of e~lcapsulated produce.
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CA 02475765 2004-07-27
~oo64i 13y providing the fi~lcrurra adjustable spring 2J~; together with the
offset drive 2g0
for at least one of the die roll', the ~aachine accommodates for die roll
wear, gelatin
thickness, and potential tablet misalignr~~ent. 1~urther, by provif~ir~g
timing belt drives
and the phase control co~zpllns, the rnachin~: can be adjusted and
synchronised for
correct arid efficient operatror~. lay providing jack screws to the die roll
rn.ounting
plates, the die roll changing is greatly facilitated inasmuch as the plates
carp be easily
removed for access to the die rolls when changing tablet shapes or replacing
worn dies.
although the upper die roll is shown in the preferred errabodiment as being
adjustable,
the lower die roll can be the adjustable die rol.i andlor both die rolls can
be .rrqo~znted as
described in connection with the a~pper die roll ~C~ of mach.ne 10 i.f
desired. 13y the
improved configuration of the mold die cavities including a step-cut in the
curvilinear
land areas, improved sealing of caplets and tablets is ach~eved. Further, by
providing
mating gub rails on each s>f the die rolls, unproved wear of the dies is
achieved.
Finally, the web, as it is dis.~ha.rged from tl~e die rolls, is collected by
an improved
mangle roll assembly which is jam resistant and, in the event of a jarrr of
web material,
can easily be cleared by ~oper~ir?g the mangle roll assembly without causing
inefficient
down time of the operation of the machine.
ion&51 It will 'oecorne apparea~t to those skilled in the art that various
modifications to
the preferred embodiments of the invention as described herein care be made
without
departing from the spirit or scope of the invention as defined by the appended
claims.
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