Note: Descriptions are shown in the official language in which they were submitted.
Vocket G3~
Backgroun~! o~ t~e Invention
The presen~ invPntion relates to a method for
coatin~ ~lass containers and, more particularly, to a
method for coatin~ glass containers o~ varying shapes with
S a layer of plastic~
Glass containers, such as glass bottles, have long
been used as receptacles for soft arinks ~nd various other
commodities since they are superior in many respects to ~thex
types of containers. 1'he consurner can see the marketed com-
modity directly if the glass is transparent. Glass con~-air.ers
can be formed in a wide variety of shapes and sizes. Addi-
tionally, glass containers are easily sanitized. Finally, the
recent growth in interest in energy conservation and in re-
source conservation has increased the attractiveness of glass
containers since such containers ~re easily cleaned and steri-
lized and thus may be recycled easily. Glass containers are
relativel~ sturdy and will hold up through a substantial num-
ber of recycling operations, although, a~ter approximately
twenty cycles abrasion marks on the glass will show.
One subskantial drawback to the glass container is
its tendency to shatter on impact with a hard surface, pro-
ducing sharp glass shards. The safety risk involved with
such breakage is hei~htened by the~fact that many glass con-
tainexs are pressur~zed ( such as bottles containing carbonated
beverages) and the shards which result from shattering the
glass con~ainer will be scattered over a relatively large area.
It has been determined that coat;ng glass bottles
with various plastic materials, can significantly reduce the
likelihood of brea};age and xeduce the scattering o~ glass
,
.
g4~
~ocket 63~3
shal^ds in the event that breakage does occur. ~t has also
becn determinecl that a suitable coatin~ properly applied to
t31ass bottles will recluce the abrasion marks and reduce
br~akage during the filling and handling pLocess thereby
5 increasincJ the number of times a glass container can be re-
cycled. Various techniques ancl materials have been developed,
therefore, for coating glass containers such as glass bot-kles.
Most commonly used are polyvinyl chloricle, poly-
~re-thane, polystyrene, ethylene-vinyl acetate copol~ners
1~ ~nd polyvinyl acetate resins; although, others incl~ding
~rethanes are disclosed in the patent literature. See, ~or
example~ U. S. patents 3,877,9~9; 3,889,031; 3,864/152;
l78,049 and 3,823,032; all of i~ich disclose utilizing poly-
~rethane materials as a component of the coating. These
~5 patent~ also disclose various methods of applying the coatings
to the glass bottle. In general it can ~e said that spraying
~nd dipping are the basic methods used. U. S. patents 3,921,575
~nd 3,73~,765 are examples of each type. A good enumeration
o~ such m~thods is given in U. S. patent 3,825,141 and 3,825,142,
~here it is stated:
"It is, of course, appreciated that a
suitable means of application of the coating
material or sheath .... to inner glass .... is --
a necessity and as examples it is sugges-ted
that any of the following may be employed de-
pending upon the manu~acturer's desire:
a. By spraying the thermopl~stic ma-
t~rial as a po~ld~r, optionally by an electro~
static spraying method, onto the hot ~xternal
sur~ace o the inner xeceptacle;
3~ b. By dipping the inn~r reccptacle,
nlaintainecl at an appropriate temperature, into
a ~luidizcd becl o the plastic material in
powder ~orm;
-3-
~ocket ~3~3
~ . B~ clipr~ing the inner r~ceptacle, if
desired while hot, illtO ~ molten bath o~ the
pl~stic m~terial or into a solution or a dis-
persioIl of such material, or
d. ~y an~ other method of providing a
sleeve type coating to an inner glass re-
ceptacle known in the art."
All of these methocls sufer from several dis-
advanta~es in regard to the ~roduction of a coated shatter-
proof bottle that can be washedand processed repeatedly,
that will resist wear and deterioration even at the points
of stress, and where the coatin~ will for extended periods
retain its required ability to prevent shattering. One of
the xeasons for this is that the above-mentioned methous
lS cannot be easily used to control the thickness of the coat-
ing layerO Additionall~, if a liquid material is used it
must ~e of a type which can be held in the dipping bath or
spray container or extended periods of time without hardening.
One possible solution to the uniform coating and
differential wear problem is to apply the coating di~ferenti-
ally to the different parts of the bottle. This is difficult
to do by con~entional spra~ing or dipping techniques.
system which does utilize a differential coating is disclosed
in U. S. patent No. 3,gl2,100 to Graham et al and U. S. Patent
No. 3,950,199 to ~ucas. ~Iowever, in the arxangement dis-
closed there, thermoplastic is applied to a band axouncl the
neck by spra~ing (U. S. patent No. 3,912,100) or with an appli~
cator head tU. S. Patent No. 3,9S0,199) and then a heat-shrink
sleeve is applied to the rest o the bottle.
~-- .
~o~ 3~3 ~ 47~
It would be desira~]e to have a system whereby
adjacent zones are coated at the same time with di~ering
amounts, thic~nesses or compositiolls. ~ile 1OW coating
methods ~or applyin~ diferent compositions are known (see
U. S. paten~ No. 3,$02,908 to ~O}IS), in that instance mul-
tiple nozzles are usecl to apply successive layers of thermo-
plastic coating ma~erial to the rotatin~ cylinders. Appli-
cant kIlOWS of no system whereby adjacent zones of a ~lass con-
~ tainer are flow coated with a liquid plastic by use of a series
of nozzle maans.
Accordin~ly, it oan be seen that a need exists for
a method and apparatus for applying a controlled plastic coat
in~ across the surface of a glass container, whercby substan-
tial numbers of glass containers may be efficiently co~tefl with
1~ a plastic such as polyurethane. Additionally, the apparatus
should ~e desi~ned for easy cl~aning at the conclusion of the
coating process.
,. .
Sul~mary of the Invention
The present invention meets this need by providing
2~ a method and apparatus for coating a ylass container (bottles,
jars, tu~es, etc.) with a layer of plastic by rotating the con-
ta;ner about a hoxizontal axis while moviny the container past
a coatiny station havin~ a plurality of liquid applicator
noæzles. ~ach nozzle means, or series of applicatQr tubes,
applies an uncured liquid plastic such as polyurethane to an
associated axea of the container as th~ container is moved past
~5-
~. . .
Do~k~t G343
the coatin~ ~tation in a direction perpcndlcular to the
container axis. Means are provided for supply.incJ prede-
termined quantities of uncured liquid plastlc (which may
vaîy in composition, amount, col.or, etc.) to respective ones
of the noz21e mean~. Meanc: are also provided ~ox rotating the
coated container slowly as the coated container moves throu~h
a curing zone and for cleanin~ the nozzle means by pumpin~
solvent therethrou~h.
With this arrangement o apparatus mealls, it is
possible to efficiently coat a 1.arge number of containers
rapidly and effectively. In generalt the preferred method
performed with this apparatus is or coating glass bottles and
is as follows: .
a~ the bottles are cleaned .in a standard bottle
washi'ng process,
b) a silane primer is applied from a solvent mix-
ture and the bottles are drie~.to remove the solvent; ~his
may be performed as a part oX the continuous flow coating pro~
cess or prior to introducing the bottles into that process,
c~ if priming is done as a pre~treatment, the
primed bottles are loaded onto the ~ontinuous.conveyor,
d) . if desired, the bottles may be passed through
. a preheat (110F - 130F) to remove any remaining solvent
from the primer and assist in flow of the uncured polyure-
~5 thane liqllid plastic,
~ ) the uncured polyurethane liquid plastic is
mixe,d and metered in predetermined amounts to each no2zle
means (for example/ four series o~ applicator tuhes varying
_ .
from 10-26 tubes each) and cast from the separate nozzle means
as the bottle is rotated at approximately 40-60 RP~I beneath the
nozzle means; tlle bottle may make one ox two revolutions per
cast cycle, each casting cycle lasting 1 - 1.5 seconds,
f) after casting, the coated bottle is moved into
a curing zone, such as an infrared oven, for a period of time
sufficient to cure the polyurethane resin; the bottle is rotated
at approximately 20-30 RPM during curing to assure uniformity
of the coating,
g) the bottles are then cooled by air blast or at
ambient temperature before being removed from the c~ntinuous
conveyor.
In a further aspect there is provided a method of
coating a glass container with a layer of plastic comprising the
steps of flow coating liquid plastic material simultaneously
from multiple nozzle means, each nozzle being fed with a pre-
determined quantity of plastic material, onto the container, the
latter being rotated about an axis, there being no movement of
the nozzles along the axis of rotation of the container, and
subsequently curing the plastic material by heating the rotating
container.
In this manner it is possible to coat glass bottles
or other glass containers with a plastic such as polyurethane
without the use of solvent sprays, dip baths or electrostatic
means~ and yet, with superior ~lexibility and control over the
amount and type o~ deposition. This enables one to coat the
bottles uniformly, protecting even the protruding por~ions, or
even to apply thicker and/or tougher coatings at such wear areas.
Likewise, the process can be used to recoat worn areas of the
bottle coating without recoating the whole bottle. The bottle
... ,. ~,
coated with a polyurethane material in accordance with the
present invention has been found to perform in a superior manner
both in terms of the durability of the coating, resistance to
abrasion and its ability to resist shattering.
' -7a-
.~
;)#
I)s-c~ct 63~3
~ ccordin~ly, it i5 ~n object o~ the present in-
vention to provi.de a method and apparatus ~or container
coa~ing in which separate coating ~luid applicator means
are provided or -each oE a numbcr of container areas; to
provide such a method and apparatus in which the surac~ areas
are coated simultaneously; and to pro~ide such a method and
apparatus in which clean up after coating may be easily
accomplished.
. Other objects ancl advanta~es of the present in-
ven~ion will b~ apparent from the following description, the
accompanying dra~ings and the appended claims.
Brief Description of the Drawings
Fig. 1 is an overall view of an embodi.men~ of the
. present invention;
1~ Fig. 2 is a side view o~ the embodiment o~ Fig. 1,
as seen looking left to right in Fi.y. l;
Fig. 3 is a vie~ illustrating the coating nozzle
arrangement of the present invention,
Fig. 4 is an enlarged partial sectional view, taken
generally along the lin~ 4--4 in Fig; 3;
Fig. 5 is an enlarged ~iew showing a coated bottle
with a portion broken away and in section;
Fig. 6 is an enlarged view showing a single nozzle;
Fig. 7 is a diagrammatic view.illustrating the
2~ motion o~ th~ nozzle carriage during the coat.ing process;
Fi.g. 8 is a view showing t.he systemic s~stem for
~upplying mcured liquid plastic to the nozzlcs;
Fig, 9 is a schematic dLagram lllustrating the
hy~lraullc system o~ the present inventi.on; and
-8~
1~9~3
Figs. lOA and lOB, when placed together with Fig. lOA
above Fi~. lOB, illustrate the electrical control circuit of the
present invention.
Detailed Description of the Preferred Embodiments
Reference is now made to Fig. 1 in which the preferred
bottle coating device of the present invention is illustrated.
The bottles are intended to be coated with an uncured
polyurethane liquid plastic, which is quickly cured under either
ultraviolet or infrared liyht. Preferred is a mixture of "A" and
10 "B" components of the type disclosed in U.S. Patent No 4,100jO10,
issued July 11, 1978. Basically, that mixture is one of a poly-
ether polyol component ("A"), which may be a difunctional, tri-
functional and~or tetrafunctional polypropylene glycol contain-
ing a suitable catalyst, and a diisocyanate component ("B") such
as an aliphatic diisocyanate. As stated in U.S. Patent 4,100,010,
an example of the diisocyanate is Hylene W from E. I. duPont de
Nemours & Co., and the polyether polyol may be one or more of
the Pluracol materials (P-410 or TP-440) from BASF Wyandotte.
It may also be a polyether-polyester polyol combination. The
20 ratio of components A:B is preferably 50-60 : 40-50. A poly-
ester polyol or polylactone polyol could be used in place of the
polyether polyol.
The mixture of "A" and "B" components of this type
cures, through catalytic actionl under heat such as produced by
infrared radiation. Accordingly, this type of arrangement will
be disclosed as the preferred embodiment; although, single com-
ponent, photocurable, polyurethanes of known types could also
be used.
* Trademark _ g _
~\~
~ ~ c,~
D~ck~t G3~3 ~9~7~ . .
Xn ei.~hel cvcnt it i9 desira~)lc to prime thc glas~
bottle with a si.lane before coatin~. As an e~ample, a n~ixture
of approxirnately 2% castor oil (Surfactol from The Baker Castor
Oil Co.~ and up to approximately 2~ silane (Dow 6020, 6040 or
6075 from Dow CornincJ Corp., which are respectiv~ly,3-(2-amino
ethylamine3 propyltrimethoxysilane, ~lyci.do~ypropyl.trimethoxy-
silane, and vinyltriacetooxysilane1 in ~ solvent (70% isopropyl
alc~hol and 30~ ace~onc) may he used~ Other known silane.primers
may al~o be used. The primers may be pre-applied b~ sprayin~
or dipping, followed by drying to remove the solvent. Alter-
natively, it may be applied as an initial step in a continuous
bottle coating process of the type described hereinafter.
In the preferred form of that process, tanks 15 and
. 17 are pro~ided to store the "A" material while tanks 19 and 21
1~ provide stora~e for the "B" material. Only one of tanks 15
anc~ 17 and ~ne OI tanks 19 and 21 will be used as a supply at
any one time, thus permitting the other of each pair to b~
refilled~ A plurality of hydraulic motors Ml, M~, ~3, and ~4
are provided for driving a plurality.of associated pairs of
: 20 p~ps which pump the "A" and "B" materials to a plural.ity o
nozzle means on nozzle carriage 23. Nozzle carriage 23 is
slidably mounted on rods 25 or motion as indic~ted, under
control of hydraulic cylillder 27.
Conveyor me~chanism 29 is driven by h~draulic motor
2S M6 and has mount~d thereQn a plura~ity of pairs of bottle ~chucks
31. ~or the sake of clari.ty only a ~ew ch~lcks are shown in Fig.
l; however, it ~.hould be understood that the chucks in the device
are mounted in pair5 all along th~ conveyor mechanism 29. ~he
conveyor may advanta~ously comprise a pair o~ chains 33 driven
by sprockets 35 and pa-qsi.n~ around idler sprockets 37. A hydraulic
motor M7 driv~s rotati.on mechanism 39 which rotates the b.o~tles
7;aJels1arly
--10~
3~'7~
Poc~t ~3~3
a,s they p~ss be~ec~t~ the noæ~.le carriclc3e 23 throug~ an area termed
the coc~ti~n~ station, ~s ,m,entio~cd, the hottles ma~r be primed by
being pre-coated with , silane prior to coatincJ. The primed
bottles are placect in the chuc~s at the left end of the conveyor.
5 The bottles are rotated and coatecl at the coating station and
then pass bene~th ~ pluxality o~ infrared lamps 41 ~7hich accelerate
the curing of the liquid plastic. A ~ure rotation arrangement
4'3 is driven hy motor ~55 and is provided to rotate the bottles
continuously as they pass beneath the lamps 41. ~he coated bottl~s
axe then removed from the chucks at the right end of the conveyor,
Cabinet 45 houses the electrical control circuitry of the present
invention.
As seen in Fig. 2, the nozzle carriage 23 may be
- shifted latera]ly by hydraulic cylinder 47 such that the noz~le
carriage will no longer be positioned above the conveyor 29.
The carriage 23 is slidably shifted on rods 49 to the position
shown by the dashed ]ines in Fig. 2 when,it is desired to clean
the system by flushing it out wlth solvent. A container may
be placed beneath the nozzle carriage to catch the solvent dis-
~charged during the ~lushing operation.
In Figs~ 3 and 4,the bottle chuck mechanism forholding and rotatin~J a bottle during the coating and curing process
is illustrated in greater detail. Each bottle to be coated is
placed o~ a chUck 31, ~hi.ch includes bottle gripping pads 51 and
2S 53. As seen in Fig. 4~ pad 53 is shaped to extend slightly into
,khe mouth o~ th~ bottle 55 ~nd thereby to en~a~e the bottle :
secuxely. I'ad 51 is shaped to conform to the bottom contour
o~ the bottle 55, hevex mechanlsm 57 may he shifted to pull pad
53 o~twardly xom the bottle against the force o~ compresC;ion
-- 11 ~
4 ~8
Do~et ~3~3
sprin~ 5~, thus p~xmittincJ the removc~l of the bottle at the com
pletion of the coa~ing process and the insertion of an uncoated
~ottl~.
Pad 51 is connected to shat 61 which is ~ournaled
in member 63 and ;s free to rotate. Rotation wheel 6~ is driven
bv belt 6S which forms a portion of the rotatioll meehanism 39
~Fig. 1). Be]t 65 ~xtends the length of the coating station
and i5 driven by hydraulic motor M7 via driving pulley 67 at
a speed which e~ceeds the speed of conve~or 29. Belt 65 there
fore engayes wheel 6~ and, backed by metal strip 69, causes
bottle 55 to rotate at approximately ~0 to 60 R.P.M. during the
coating process. A rotation belt is likewise included in the
rotation mechanisrn 43 for ro~ating the bottle durin~ curing of
the plastic, preferably at a speed o approxlmately 20-30 R.P.M.
Rotation at the coating station ~nd during curing results in a
uniform distribution of liquid plastic and prev~nts streaks or
other imperections in the coating layer.
A pre heatincJ sta~ion ~no~ shown~ may be place~
before ~he coa~in~ station for the purpose of pre-hea~ing the
bottles to around 110-130F in order to aid the flow o~ the
coa~ting onto the bottle. This is not required,however/
As seen in Fig. 5, a typical soft drink bottle which
is to be coated wi.th a layer 71 of plastic may vary somewhat
in ci.rcumference along it~ lenykh and may have ridges or other
points of sharp surface curvature. It will be appreciated that
the volume of li.quid plaskic which would be desirable to app~y
may vary along the lenc3th of th~ bot:tle. The bottl~ of Fiy. S
has beell divided into ~our zones and it is c1ear that if a
coatin~ o uniform thickness were desired, a greater volume of
~1~L9~'~ .
Doc);e~ G3~3
plastic ~70uld ~e required for zone two, for example, than for
zone four. ~dd;.tionall~l it may b~ desired to appl~ a thicker
and/or tougher coating of plastic to the surface areas o~ the
bo~tles which receive the gxeatest stress and wear. Typically,
these areas are the areas with the laryest cixcumference and
the rim around the bottom of the bottle.
In order to provide ~le desixed thicknesses of
plastic in each zone, a plurality oE liquid appllcator nozzle
means 73, as seen in Fig. 3, are provided. The nozzle r,leans
for each zone has its o~n supply of uncured liquid plastic 75
and applies diferent predetermined quantities o uncured liquid
- plastic to its associated zone during the coating process.
Accordin~ly, the different zones of the bottle may be coated
with plastic o differing thickness, composition, color, etc.
Fi~. 6 illustxates ~ne of the nozæle means 73 in
greatei--detail. A fitting 77 connects each of a plurality of
fluid carrying tubes 79 to its associated liquid plastic supply.
The number of tubes 79 and the spacing between the tubes in an
individual nozzle means will vary in dependence on the bottle
contour. It has been foundl however, th~t between 10 and 26
tubes, spaced apart approximately 1/8 to l~lOinch, may be used
for each nozzle means in the present emhodiment. The tubes
preferably have .022"I.D. and a .039'l O.D. Spacer bar 81 holcls
th~ tubes 79 spaced apart at desired distances. For application
of a uniorm thickness coating across each of the four zones of
a 1/2 or 1 liter bottle of the type shown in Fig. 3, 18 tubes
are used in each of the irst three noæzle means and 12 are used
in the ourtll. Such a nozzle means arrangement is preferably
used with a flow rate of around 1~5 g/min. to deposit~ 13 15
.
.
-13-
.
~' ^ , ' .
Dockct G393 ~ 34~
~ram~s of licluid plastic per bottle to a thicklless of 100 250
m'icrons .
Fig. 7 is a dia~rammatic representat.ion of the coatin~
process lookin~ at the devicc from the same sicle as in Fiy. 1. The
initial positi.on of a pair of bottl~s 55 at the coatiny station is
shown by the solid circ].es. A pai.r of bot-tles 55' which have
just been coated are spaced along the conveyor ~y a distance 81.
The pair of bottles are spaced apart from each other by a distance
83~ The pair of bottles 55 will be coa~ed simultaneously by two
~ets of noz~le means 73. One of a plurality of supply tubes 84
provides the uncured liquld plastic to nozæle means which coat
correspondin~ zones on the two bottles. The bottles 55 are coated
as they rotate and, at the same time, move through the coating
station on the conveyor by a distanoe 85. The nozzle ~eans 73 are
also moved along the conveyor a corresponding di~tance 87 such
that they remain above the respective bottles 55 duri.ng coatin~. ;
Coating of the bottles then ceases but the nozzle means continue
to move with the rotating bottles a distance 89 such that the
nozzle means themselves will be completely drained of coating fluid.
The nozzle means 73 are then returned to their initial position
to await the movement of the succeeding pair of bottles irito
position at the coating station. Alternatively the continuous
movement of the bottles may be temporarily halted during the coating
operati.on, in ~hich case movement of the noz~le means lS not
necessaryO
~ eferring now to E'igs. 8r 9, 10~ and lOB, the systemic
hydraulic and electrical systems for the device of the present
inventioll are shown. ~s seen in E`ig. 8, the "~" material is stored
in tanks 15 and 17, and the "B" material is stored in tanks 19
~0 and 21. All four tanks are partially evacuated. ~s mentioned
previously dual tanks ar.e used for skora~e of each material so
1~ -
,
.. . . ... , . .. , .. .. _ .. . . .... ~ . :.. .. ..... ....... .. ... . .
L9~7~
pockct 63~3
that one t~nk may be refilled while the materlal is supplied
to the coating de~ice by ~he other tank,
~'~" matcrial ~s supplied through line 209 to pumps
Pl~r P2A, P3A, and P~. Similarly, "B" material is supplied
thxough line 211 to pumps PlB, P2B, P3B, and P4B. H~draulic
motor Ml ls mechanically coupled to pumps Pl~ and PlB; hydraulic
motor M2 is mechanicall~ coupled to pumps P2~ and P2B; hydraulic
motor M3 is mechanically coupled to pumps P3A and P3~; and,
hydraulic motor M4 is mechanical''y coupled to pumps P4A and P4B.
lQ The mechanical cou~ling between each o~ motors Ml-M4 and their
associated pumps is such that each set o~ pumps will p~mp the
required proportion of ~ and "B" material as the motor rotates.
Val~es Vla, Vlb, V2a, V2b, V3a, V3b, V4a, and V4b
are coupled to the pump outputs and, when in the positions shown
in Fig. 8, supply the "A" and "'B" material to mixers 213, 215,
217 and 219. These mixers ma~ simply be tubes which contain
a plurality of st~tic vanes or baffles which will cause the fluid
pumped therethrough to be mixed thoroughiy. Nozzle means 221,
223, 225, 227, 229, 231, 233, and 235 simultaneously supply the
2a uncured liquid plastic to the ~our zones on two bottles. During
the normal coating operation, all o~ the systemic valves will
remain as shown in Fig, 8. Control o~ the application of uncured
liquid plastic will be accomplished by controlling the operation
` o~ hydraulic motors ~l-M4.
2S At the end o~ a period of operation, it Inay be
desired to shut down thc m~chineO As discussed above, it is
then nec~ssar~ to clean, the portions o th~ syst~mic system
having the mixed "A" and "B"'material be~ore this material cures.
For this purpo5e, a tank 237 is provided contalning a solvent
to dissolve the mlxed "~" and "~" materlal be~ore it sel~çures.
~ 15 ~
:
L9~
Doc~et ~3~3
Pressuri~ed air ~ rovided throucJh valve 23~ s.~lthat the flush
tank is hel~ pressu~i~ed, ~1hen valves V5a and V5~ are actuatecl
into their B positi.ons by solenoi.d actuatecl valve 2~1, the solvcnt
fluid will flo~J through lines 243 ancl 245.
Solenoid actuated valve 247 supplies air through
. line 249 to the pilot on the A side of valves Vla, V]b, V2a,
V2h, V3a, V3b~ V~a, and V~b. Likewise, the pilot for the B
side of these valves is connectea to line 251, It is clear,
therefore, that when valve 247 is actuated such that the air
is supplied to the B sides of valves Vl-V4 on line 251, the
solvent in lines 243 and 245 will ~low throu~h valves Vl-V~,
mixers 213-21~, and nozæle means 221-235, Aftex a sufficient
quantity of solvent has flowed through the lines, valves V5a
and V5b are returned to their A positions, Valve 253 is then
actuated and pressurized air is supplied to lines 243 and 245
to flush these 1.ines and their associated v~lves and nozzles
of all solvent and uncured plastic. The application of solvent
and air to these lines may be repeated to insure adequate cleaning.
Reference is now made to Fig. 9, in which the hydraulic
portion of the present invention is illustrated schematically~
~lectric motor 255 drives hydraulic pump 257 and provides the
sole source of po~er for the hydraulic system. .Motor 255 may
typically be a 10 horsepower, 1800 R.P.M., 3 phase, AC motor.
Hydraullc .~lUid is supplied on line 259 to valve 261. Valve
261 is, in turn, connected ~o val~es 263,265, 267, and 269~ When
pump 257 is being dx~ven and valves 261-269 are actuated, adjustabl.e
pressure and temperature compellsated valves 271, 273, 275, and
~77 pxovide hydraulic fluid t.o hydraulic motors Ml, M2, M3,
and ~5~ respectively, Ag di.scussed above ~n regard to Fig. 8,
- 16
' ' ' . .
3~
I)ocket ~3~
motors ~l thxoucJh M~ pxovide ~he driving power to the systemic
pumps which pump the u~cured liquid plastic to the nozzles.Motors
M1-M4 are, therefore, periodically driven durin~ the coating
opexation under the control of valves 261-269.
~Iydraulic fluid is also supplied to line 279 by
pu~p 257 and motors MS, M6, and M~ are provided with hydraulic
fluid throu~h valves 2~1, 283, and 285 via valves 287, 289, and
291~ ~lotor M5 is connected to drive the cure rotation belt -
mechanism 43. Motor M6 dri~es the conveyor 29, and motor ~7
drives the cast rotation mechanism 39. Additionally, hydraulic
c~linders 27 and 47 are operated to move the nozzle carriage,
Cylinder 27 is the traverse cylinder mechanism for moving the
carriage along the conveyor during the coating operation. Cylindex
27 is supplied with fluid through valves 296 or 297 via valve
15 - 299. 5imilarly, cylinder 47 moves the carriage laterally such
that flushing may be carried out to one s~de of the conveyor.
Valve 301 applies ~luid to either valve 303 or valve 305. Pressure
piloted check valves 307 insure that the cylinder 47 maintains
the desired position when set.
Figs. lOA and lOB illustrate the electrical control
circuitry ~ox the present invention in detail when placed
to~ethex with Piy, lOA positioned above Fig. lOB. In Fig. lO
the relay coils axe designated with "R" and a number; the o
corresponding rela~ coil contacts have the same designation
~5 ~ith an ~dditional letter~ Similarl~, timer coils are given
a numbered 'tT" desi~nation with the timer contacts designated
with a corxesponding number and an additional letter, Each
timex contact has associated therewikh a three symbol code
consistlhg of "Xls" and "Ols", ~n ^'X" indicates a closed
- 17 ~
3~
Doc~ct 63~.
contact and a~ ~'O" indicates an open contact. The first of the
three symbols indicates the contact state prior to the timinq
operation; ~he second of the three symbols indicates the contact
state durin~ timin~; and, the third of the three symbols indicates
the contact state after timing but pri~r to reset.
Switch 30~ is closed to apply power to transformer
309 vi.a fuses 311. When the POWER switch 313 is momentarily
closed, powex is supplied through fuse 315 and switch 317
to lines 319 and 321. Light 323 indicates that the power has
been turned on. Switch 317 is a safety switch which is closed .
only when the control panel cabinet is closed.
I~hen START s~itch 325 is momentarily closed, relay
Ml locks itself in thxou~h normally open contacts Mld and eloses
normally open contacts Ml.a-Mlc, resulting in power being applied
lS to motor 255. Motor 255 is mechanically linked to pump 257 (Fig~
9) and powers the hydraulic system. Relay coils Rl are also ~
energized, causing normally open contacts Rla-~lg to be elosed.
~hen switch 327 is closed, solenoid A will be
enexgized, thus actuating valve 289 (Fiy. 9) and causing the
eonveyor to be powered by motor M6. When switch 329 is closed,
æolenoid B ~ill be energized, thus actuating valve 291 ~Fig.
9) and causing motor M7 to power the coating rotation meehanism.
.Similarl~, when switch 331 is closed; solenoid C is energized,
thus actuatin~ valve 287 and causing motor M5 to power the cure
2S rot~tion mechanism, Switches 333, 335, 337 and 339 con~rol appli-
eation of power to solenoids E, ~', G, and H, respectively and,
in turn~ control valves 263-269 ~Fig, 9). Since these valves
provide the hydraulic fluid to motors Ml-M4, switches 333.-339
must be closcd ~or application of li.quid plastic to the four
zones of a bottle,
18 -
47~
Dock~t ~3~3
~ ode swltch 3~11 may be sct lnto a manual tllode operati.on,
in which cas~ r~l~y coil ~2 ls ener~iæecl, or intQ an au~omatic
mode, in which c~se relay coi.l ~3 is energlzect. ~ssuming that
switch 341 is s~-~ into ~h~ automatic mode, normally opened contact
; ~3a will be closed, thus supplying power to :line 343. Sensor
345 scnscs the pres~nce of a bottle c~uck ~t a desired position
on the conveyorO T~pically th~ sensor will eneryi.ze coils Tl
.and Tl', throuyh contact Tlla, as a bottle approaches the coating
station. Contact Tlb will immediately close, thus energizing
!~1 the coil of timer T~. Ti~er Tl controls the movement of the
nozzle carriage alon~ the conveyor at the coating stationD Timer
T2 insures a short delay of approximately 0,2 seconds a~ter
the initiation of carria~e rnovement before the coating process
- is begun. When ti.mer T2 times out, contacts T2a will close,
thus energizing relay coil. X~O Relay contacts R4a then close
energizing timer T3 which controls the duration o~the coating
operation.
Timer contacts Tlc and Tld are connected in series
with co~l R5 such that R5 will be energized only during.the
;~0 ~orward traverse operation. Similarly, timer contacts T3c and
T3d are connected in series with relay coil R6 such that this
relay coil will be energized only during the coating operation.
Timer ~r3 will typically be o~ a duration such that, even thou~h
it is st.~rted.subse~uent to timer Tl by a time equal to the timing
cycle o~ timer T2, timer T3 will complete its timing cycle prior
to the completion of that of timer Tl.
Since relay R3 will be ener~.ized when -the mode
switch 3~1 is in the automatic mode, relay contacts R3b will
be closed in this mode, When relay coil ~S is ener~ized, the
- 19 -
'
1~'3~8
Dockct 63~3
COIlt~C~S R5a wil1 close, thus ~nergizirlg solenolcl I. ~s se~n
in Fig. 9, thls will actuate,valve 299 and cause hydxaulic cylinder
27 to ex-tend. The rate of such extension ,is precisely controlled
by valve 297 such that th~ nozzle carriage will move in synchronism
with the conveyor.
Contacts ~3c will ~e closed when the device is
in the automatic mode and contacts R~a will be close~ during
the timing c~cle of coating timer T3, energizing solenoid J via
limit switches LS], LS2, LS3, I.S4, and LS5. Limit switch LSl
;10 is positioned such that it will be closed when the nozzle carriage
i5 positioned over the conveyor (rather than in the flush position~.
~imit s~itchas LS2-LS5 are associated with valves Vl-V4 (Fig. 8)
a.ld are closed when those valves are in their A positions. Solenoid
J will therefore actuate valve 261 (Fig. 9),causing motors Ml-
M4 to be operated and resulting in pumps Pl-P4 (Fig. 8) pumping
~,the uncured plastic liquid to their respective nozzle means 231-
235.
~,When timer T3 times out, coil R6 will be deenergized
;and thus deenergize solenoid J, terminating the coating operation.
2b Subsequently, timer Tl will time out, deenergizin~ coil R5 and
solenoid I. Valve 299 ~Fig. 9) will be deactiva~ed and the cylinder
27 will retract, ~o~ing the nozzle,carriage ~ack to its starting
position to await initiation of a subsequent coating operation.
Contacts R6b will be closed during each coating operation, in-
~S crementing counter 344 and providing a ~unning total of the numbero~ coating operations performed.
' When it is desired to control manuall~ the application
of the plastic liqui~ by the noæzle means, the mode $witch 341
i~, swi~ched into the ~*~NU~L position, energizing relay R~. Contacts
~ 20 - ,
.
.
34~
Docket G3~13
R2a are thcll clos~cl alld solerloid J may bc eller~lzed by closing
the ~OUI~ switch 3~5~ The nozzle carria~e~ will remain stationary
and plastic liquid will be supplied to the nozzle Ineans as long
as SWitC}l 3~5 is closed, Th~ manual mode will typically be
used only in settincJ up the machine, c~ecking i~s operatian~
and during the flush operation.
The balance o~ th~ electric circuitry controls
the flush operation in which solvent and compressed air are forcecl
through portions of the systemic system. ~qhen it is desired
to flush the system, the mode switch 341 is set into ~he ~NUAL
position, energi~ing xelay coil R2 and closing contacts R2a.
Flush position switch 347 is then closed, energizing solenoid
K, and thus actuating valve 301 (Fig, 9) to cause hydraulic cylindex
47 to extend. This results in the nozzle carriage 23 beiny shi~ted
laterally into the flush position at the side of the conveyor.
Flush switch 349 is then closed, energizing solenoid L through
contacts R2b and limit switch LS6. Limit switch LS6 is closed
when the nozzle carriage 23 has been shited laterally into
the ~lush position. Energization of solenoid L results in valve
247 (Fig. 8) bein~ actuated and causes valves Vla-V4a and Vlb-
V4b to be moved into their respective B positions. When val~es
Vl-V4 are in their flushing positibns, limit switches LS7-LS10
will be ~losed~ thus energizing relay R7. Contacts R7a will
open, th~reEore, positively prev~nting inadvertent actuation
o~ solenoid J by closiny switch 345. Contacts R7b will close,
loc~ing in relay R7 and maintaining power to solenoid L.
When xelay R7 is energized, r~la~ contacts R7c
will be closcd, thus enexgizing timex coil T~ Contacts T~a
will immediatcly supply power to solcnold M which will actuate
~ 21 -
~1~L9~8
Doc~t 63~3
.
valve 2~1 (Fi~ 8~ ~nd rnove valves V5a and V5b tFig. 8) into
theix B positions~ Solvent will. now be suppliecl from tank 237
through valves Vl-V~ to the mixers and noz~les~ When timer T~
times out, contacts Tga will open, clecnercJiæing solenoid M, and
terminating the flush operation~ Simultaneousl~ contacts Tgb
will close and energize solenoid N through contacts l5a. Solenoid
N will actuate valve 253 (Fic3. 8? to supply pressuxized air to
lïnes 243 and 245. Pressurized air will be forced through the
systemic system until timex T5 ~imes out and contacts T5a open
to deenergize solenoid N. ~hen this occurs, contacts T5b will
close, energizing timer T6 and, at the same time, solenoid M
via contacts T6a. Timers T5, T6, and T7 may be of the type
having the time:~period determined by an R-C time. constant in
which a capacitor i.s charyed through an associated resistor.
The flush operation will thus be repeated for the
duration of the timing cycle of timer T6 When timer T6 times
out, solenoid ll~ill be deenergized and contacts T6b will close,
with the result that timer T7 will be energized. Power will be
supplied.to solenoid N through contacts T7a,thus resulti~g in
air being supplied to the systemic system for the duration of
the timing cycle o~ timer T7. When timer T7 times out, solenoid
N will be deenergized and relay coil R8 will be energized through
contacts T7b. R8 will, in turn, open normally closed contacts
R8a, thus deenergizing coil R7 and pxeventing any further flush
operation, Contacts R7b will then open, removing power from
solenoid L and thus returni.ny valves V1--V4 to theix A positions.
Contacts R7c will also open, thus precluding operation of solenoicls
M or N. The 1us~l opcration is completecl by actuation of switch
351 which, through contacts R2c and R7~, energizes solenoid 0.
0 This causes valve 301 (Fig. g~ to apply hydraulic ~luid to cylinder
- 22 -- .
.
Doc};et ~3~3
47 such th~t the no~le c~rria~e is returned to its coatln~ position
above the collveyor,
While the method here.in described, and the form
of apparattis for carrying th.is method into effectr cons-titute
preferred embodiments of t~e invention, it is to be understood
that the invention is not limited to this precise method and
form of apparatus, and that changes may be made in either without
departin~ from the scope of the invelltion.
- 23 ~
