Note: Descriptions are shown in the official language in which they were submitted.
~; ~
RP-8001-M19
'-:
.
~03770~
SPECIFICATION
:
This invention relates to an improved process and
apparatus for coating articles of manufacture and more
particularly concerns the production of shatter-resistant
glassware (i.e., bottleware). In conjunction herewith,
developments that might more broadly be characterized as
article orientation and transfer related are described in
combination with conventional fluidized bed apparatus and
oven constructions.
It should be understood that prior art polymer coat-
ings and techniques for the application of same to glass-
ware, and in particular bottles, have long been known and
practiced in the industry. These coatings have, however,
been employed, for the most part, to protect the basic
glass construction from surface abrasions and the like.
Such abrasions or other defects substantially reduce the
inherent glass strength and therefore obviously suhiect it
~ to a higher incidence of failure.
- The coatings referred to have taken the form of thin
protective films bonded to the glass surface and in most
respects exhibit tough but brittle characteTistics.
These have served well in providing the intented protection
in preserving glassware integrity. However, such cannot
and do not render ware "shatter-resistant" or substantially
change the fragmentation characteristics of ware that is
broken while under internal pressure.
,,
-1- ~k
` 103770~
In the latter respec:t, it should also be recognized
that certain glassware, particularly glass aerosol contain-
ers, have been pro~ided with polymeric protective sheaths.
- These are indicated to be resistive to glass fragmentation- 5 under conditions of failure but such have been inapplicable
for use in the vast majority of glassware applications.
For example, most such coatings are of thicknesses which
economically prevent their use or adoption in many fields.
Likewise7 these have not exhibited criteria which would
enable their use in bottling applications where severe
cleaning and other processing techniques dictated by the
contained product are encountered.
The application here considered has therefore been
directed primarily to those containerization areas employ-
ing internal pressurization where known aerosol bottle
coating techniques are inapplicable. These are principally
considered to be carbonated beverage bottles and the like
which, of course, due to their pressurized state, are sub-
ject to severe fragmentation in certain instances of
failure. In reiteration, it should be understood that the
film coatings first mentioned above help in reducing the
incidence of failure here discussed but under conditions of
failure will not necessarily decrease the severity of frag-
mentation.
Techniques and apparatus for the application of coat-
ings to containers as are here disclosed establish that
certain adhesive characteristics between the glass and
,
' 103770t3
polymer envelope dictate the acceptability and applica-
bility ~or creation of the "shatter-resistant" container
desired. SimilarlyJ other polymer properties such as
elasticity, toughness, etc. contribute to the overall
effectiveness of the coating in producing the "shatter-
resistant" container Likewise, processing during coating
contributes significantly to the creation of a suitably -~
adherent polymer sheath having surface texture continuity
and transpalency acceptable to the bottling trade.
- The invention contemplates use of thermoplastic poly-
- mers as the "shatter-resistant" coating, for example poly- :
ethylene polymers and copolymers have been found to be
quite satisfactory for use in the process. The coating
, . . . .
process employing such particulate resins dictates that
careful controls on glasswar~ preheat and curing tempera-
tures, imme~sion times and the like be maintained to assure
production of a properly adherent coating. It is also pre-
ferre~ that the polymer coating be applied to the ware
using fluidized bed techniques which, in conjunction with
the heating, etc., ~efer~ed to may be operated as a con-
tinuous line, optionally in concert with typical bottle
forming machinery.
ln addition, particular apparatus developments and
improYements have also contrlbuted to the success of the
overall process and coated "shatter-resistant" bottle
product. Unique ware orientation and an improved chuck
.
--3--
~`
` `
~ 03770~
assembly are employed to present the ware to the coating
medium. Further, and in conjunction with the chuck assem-
bly employed during actual particulate polymer, coating,
. improved clamping mechanisms are employed. These are
adapted to grip a plurality of heated ware simultaneously,
hold the ware firmly in a steady upright position through
. all motions of the transfer apparatus upon which same are
mounted, and to be immersible within a fluidized bed of
:; thermoplastic polymer resin during apparatus movement with-
lo out the adherence or an accumulation of resin thereto.
-- Prior clamping devices used in conjunction with appara-
-. tus of this. type, have adapted for position-
.~ ing in close proximity only with the fluidized bed surface. .~
Accor.dingly, the degree of bottle immersion was dependent .-~
,.~ , , .
upon the bed surface characteristics around each such bot-
tle. These characteristics as might be anticipated were
somewhat inconsistant and therefore the coating parting .~
line varied slightly from bottle to bottle. Furthermore, :
: . such techniques resulted in a glass exposure in the bottle ~:
neck area that is preferably covered.
The chuck assembly and in particular,.the clamping
mechanisms supported thereon are constructed so as to
wholly encapsulate the bottle finish and for immersion
into the particle bed during the apparatus dip cycle.
lmmersion of the clamping mechanism is facilitated by a
unique clamp cooling arrangement that cools each clamp
member or jaw assembly continually and likewise serves as - :
a purging means for the bottle interiors during dipping. ~ ~ .
'
. -4~
:, ' ' - ' ,: '. :
10377~
Hereinabove and throughout the specification and
claims reference is made to a thermoplastic "shatter-resistant"
coating. It should be understood that this terminology is
employed in the same sense as would phraseology such as shatter
proof or immune from substantial fragmentation. More part-
- icularly, this is a characteristic exhibited by the thermoplastic
coated glassware that has been processed in the manner and by
apparatus more fully described below. It is apparent therefore
that the principal objective of the invention is the production
of a "shatter-resistant" bottle suitable for use where internal
bottle pressurization is anticipated and which by design and
definition will substantially minimize bottle fragmentation
. .
in the event of such a pressurized bottle failure.
Thus, in accordance with the present teachings, a
clamping mechanism is provided which is adapted to grip an
article at one end thereof and being suitable for immersion into
a first fluid medium. The mechanism includes a split clamp
ja~ assembly having at least two mating members with a recess
therein of the approximate size and shape of one end of the
article so as to firmly grasp yet loosely surround the article.
A support arrangement is provided mounting the mating members
in juxtaposition and opposite one another. Actuating means
is provided interconnected with the members to alternately move
the members into contact with one another and then into the
juxtaposition responsive to predetermined signal means. At
least one of the members has a conduit communicating with the
recess with a fluid source connected to the conduit and recess
for propelling a second fluid medium through the conduit and
recess in such volumes as to exclude the first medium therefrom.
It should also be apparent that other significant
advantages offered by coated bottles of this type include, for
example, practical elimination of bottle-to-bottle contact glass
~ - 5 -
1037~08
abrasions, considera~le reduction in ~ottling and filling line
noise, and enable shipping carton redesign wit~out partitions.
Additional ob~ectives and advantages not enumerated
will, however, also become more apparent upon continued
reference to the specification, claims and drawings wherein: ~ :
Fig. 1 is a top plan view of typical bottle coating
line as employs the immersible fluidized bed dipping apparatus;
i' ~ .. , ",
. '
.: .
.
.
~ 5~ -
C
.. . . .
:
103770~3
; Fig. 2 is a side elevational view of the fluidized bed
dipping apparatus;
Fig. 3 is a partial perspective of the fluidized bed
dipping assembly also partially broken away to expose the
;. ~
interior thereof;
Fig. 4 is a partial plan cross-sectional view of the
:, dipping assembly taken along line 4-4 of Fig. 3 and which
is broken away so as to expose only one of the plurality o~
chuck assemblies mounted thereto;
10Fig. 5 is a partial elevational cross-sectional view
o~ th~ dipper assembly taken along line S-5 of Fig. 4 and
,~ .
i also exposing an end elevation of a single chuck assembly;
,. ~
Fig. 6, appearing on the page containing Fig. 4, is a
side elevational view of a chuck assembly in its closed position;
. Fig. 7 is a top plan view of a chuck assembly in the
open position;
Fig. 8 is a side elevational view of a chuck assembly
in the open position;
Fig. 9, appearing on the page containing Fig. 5, is an
enlarged partial cross-sectional view of a clamping mechanism
taken along line 9-9 in Fig. 4;
Fi8. 10 is a side elevational view showing the fluid-
ized bed dipping assembly and combined bottle orientation
device;
Fig. 11 is a partial front elevational view of the
bottle orientation device taken along line 11-11 of Fig.
10;
- -6- ,
. ' .
'
'~
' ~
.' 1037qO~
Fig. 12 is an end elevational cross section of a
bottle pusher element taken along line 12-12 in Fig. 11;
and
Fig. 13 is a top cross-sectional view of a bottle
orienter push plate taken along line 13-13 in Fig. 11.
As indicated above, the development of a "shatter-
resistant" bottle demands that the polymeric resin employed
possess several attributes including: adequate physical
properties, feasibility of application to the substrate
surface, and favorable environmental qualities. These
applied resin coatings ideally are characterized by a high
degree of toughness along with the capability of substantial
elongation when subjected to sudden or instantaneous load-
ing at both room and refrigerated temperatures. Likewise,
to be effective in their performance under filling and
breakage conditions, the resin should adhere to the glass
substrate. The adhesive characteristic has been found to
be of significance if an integral contiguous substrate/
polymer coating relationship is to be maintained under
hot filling, caustic washing and sterilization conditions.
Similarly, under severe strain and upon failure, especially
when under internal pressurization, the proper polymer
qualities for adherence will assure the retention of
glass fragments by the coating. If, however, adhesion is
too great in many instances, the coating itself will frag-
ment in a reaction similar to that of the glass substrate,
and, if insufficient adhesion is achieved once the coating
fails (i.e., splits or otherwise opens), glass fragments
will be propelled through the opening, out and away
from the polymer envelope.
--7--
- . . :. : ' ' . , .. .: ...... . . .
` ~037708
Various polyethylene polymers, copolymers and the like
will meet these criteria. It should be recognized that other
polymers may be similarly tailored for use in the process
described and that variations in the polymer properties may
be tolerated depending upon the desired resultant effect.
Referring now to Fig. 1, it will become apparent that
the basic process steps for the application of this "shat-
ter-resistant" coating to bottleware include a preheat
cycle, a particulate coating application and a coating
curing or fusing procedure. These basic steps as outlined
have, of course, been employed in numerous coating appli-
cations, however, as applied to the shatterproofing of
glassware several specific modifications thereof in the
form of specific resin formulations and time/temperature
relationships e-ffect the desired end results. Likewise, --
it should also be apparent that the three basic steps may
be expanded or incorporated with typlcal glass forming
processes now practiced so that a newly formed bottle may
proceed directly to and through the various required coat-
ing steps.
Further, in the event certain glass or resin composi-
- tions require, a priming step may be employed to achieve
the desired degree of adhesion between these components.
This, it should, however, be understood, is not contem-
plated as a required procedure in the preferred form of
the invention. Various primers including silicone emul-
sions and chromic and polyacrylic solutions have been
--8--
:
found to be effective in improving the bond between resin
and glass.
Similarly, subsequent to curing, fusing or sintering
the bottle coating, it may be desirable to apply a lubri-
cant to the resin surface and/or to reheat the ware coating
and thereafter quench same to improve the clarity thereof.
Lubrication is, of course, intended to impart a slipperi-
ness to the surface thereby reducing the coefficient of
friction of the resinous material and enhancing the flow
characteristics of the finished bottles during further
handling. Several waxes have been found to be particularly
effective and include those having a silicone-wax composi-
tion, carnuba waxes and silicones. In addition, it has
been found that to effectively label polyethylene coated
bottles the resin coating surface should be sensitized by
flame treating means. A 1 to 5 second exposure is suffi-
cient and thereafter labels may be applied using any of
several glues including jelly-gums, casein glues and ace-
tate adhesives.
The overall apparatus arrangement or combination used
in effectuation of the indicated process include: (l) a
bare bottle uncaser 10, a box conveyor 12 and a coated
bottle caser 14; (2) a single line bottle primer pre-heat
oven 16, a prime spray or coating unit 18 and a push-bar
stacker 20; (3) a polymer coating preheat oven 22 and
conveyor 24, a fluidized bed and bottle transfer or dip-
ping mechanism 26, and curing oven 28 and conveyor 30;
and (4) cooling section 32, waxer 34, flame sensitizer 36
and automatic inspection station 38.
. - . ,
, .. . .
~037708
In the instant process, the ware moves with the pre-
heat wire mesh oven conveyor or conveying assembly 24 into
and through the gas fired preheat oven 22. Within this
oven the bottles are brought to a relatively uniform tem-
perature of between about 400F and 600F which can be
accomplished with about 12 minutes' exposure from a cold
start. It should be appreciated though that various other
oven types may require longer or shorter time exposures
depending upon type and performance capabilities.
Immediately adjacent the terminal end of preheat oven
22, best seen in Fig. 10, is an article orientation mech-
anism 40 and the fluidized bed coating apparatus and trans-
fer mechanism 26. The orientation mechanism 40 aligns
the bottles both longitudinally and transversely of the
path of travel of conveyor 24 and thereby prepositions
same for engagement by the transfer apparatus.
In the preferred embodiment, it is contemplated that
the bottle coating will be applied by consecutively dipping
plural units of preheated ware into a fluidized bed of
particulate resinous material as is above described. It
is imperative that the preheated ware be firmly held in a
steady state as they are inserted into the bed so that
uniformity of coating can be maintained from bottle to
- bottle. Furthermore, it has been found that in order to
provide a uniform coating parting line on the bottle necks
it is a practical necessity to shield the bottle finish
and immerse the shielding fixture along with the bottle
into the fluid bed.
-10-
~03770~
As alluded to above the parting line cut-off problem
is created by the non-uniformity of the fluid bed surface
during bottle immersion. However, immersion of the clamp-
ing assemblies creates additional problems hitherto con
sidered insurmountable. For example, ~1~ the bottle finishes
having to be completely shielded thus necessitating a very
accurate bottle alignment so that upon clamp closing the
bottle necks are properly centered between the jaw assem-
blies thereof; ~2) the bottles being at elevated te~pera-
tures, between 400F and 600F, necessarily will conductive-
ly and convectively heat the clamping mechanisms thus also
sensitizing them for acceptance of the polymer coating, an
obviously unacceptable condition; and, (3) a purging med-
ium or other protective means must be employed to assure
the exclusion of polymer particles reaching the finish
area or bottle interior without disturbing parting line
uniformity.
This apparatus, more fully described hereinafter,
incorporates a plurality of clamping mechanisms in an
overhead chuck assembly that grasps the ware as it is
moving with conveyor 24, initially moves that ware to a
coating position and thereafter transports the coated
ware to and deposits same on conveyor assembly 30.
; The conveyor assembly 30, therefore 9 has deposited
on it hot, exteriorly coated ware that is incompletely
fused. Such conveyor thus passes through a fusing or
curing zone or oven 28 (gas fired) and onto a circulating
air cooling section or zone 32. Again, it should be
appreciated that curing or fusing oven temperatures con-
tribute significantly to the final product characteristics
.. . : .
: . .:
: ....... ''.
~03770~
and that 450~ to 600F represents an acceptable temperature
gradient. Preferably, however retention of the coated ware
at a 450F to 475F temperature level for a nominal 8 minute
period produces ideal results. This may also vary depending
upon oven construction and heat generation means. At the
terminal end of conveyor 30 the coated ware is transfered into
a single line configuration for passage through lubrication
apparatus or waxer 34, on to the flame sensitizer 36 and
through the inspection station 38.
A better appreciation of the several apparatus elements
and improvements above-mentioned, may be obtained by refer-
ence to Figs. 2-13. For example, the bottle or article
orientation mechanism 40 may be seen in more detail in
Figs. 10-13. Such orienter, as is best seen in Fig. 10,
; 15 extends across and above the conveyor 24 and is in relative-
ly close proximity to both the exit of the preheat oven 22
and the pick-up point of the fluidized bed and transfer
apparatus 26. Accordingly, as heated bottleware exits the
- preheat oven it is engaged by the orientation mechanism
` 20 and one or more rows of bottles are realigned on conveyor 24
so that they can be properly grasped at the mentioned pick-
up point.
The orientation mechanism 40 includes a supporting
; structure 42 that is affixed either to the frame of con-
veyor 24 or to others of the associated apparatus fixtures.
Within such structure is pivotally mounted a frame assembly
44 including end members 46 and cross pieces 48. Depend-
ing upon the conveyor width traversed it may also be
necessary to reinforce at least one such cross piece as
-12-
.
;--~
: ~0377013
is done with channel member 50 (Figs. 11 and 12).
As indicated frame assembly 44 is pivotally mounted
to structure 42 by the bearing supports 52 and is oscil-
lated between rearward and forward positions by fluid
cylinders or first actuating means 54 that are similarly
mounted on opposite sides of the conveyor to supporting
structure 42. Likewise, the frame assembly is linked with
the bearing supports through another set of fluid cylinders
or second actuating means 56 that are adapted to vertically
adjust the height of such assembly during the operational
cycle of the apparatus, which is more fully described here-
inafter.
Cross-pieces 48 have affixed, preferably to both sides
thereof, a plurality of pusher units 58. Accordingly, such
units are adapted to engage and orient two rows of ware
simultaneously. In some instances, it, of course, might be
equally advantageous to use only a single row of pusher
units or to enlarge the frame assembly 44 to accommodate
three or more rows thereof. Similarly, the number of pusher
units 58 that are positioned transversely of conveyor 24
along pieces 48 may be varied to accommodate the number of
bottles per row that are stacked on the conveyor.
Each pusher unit 58 is comprised of a pusher plate 60
supported onthe terminal ends of two rods 62. These rods
are in turn supported for vertical sliding movement in
bearing mounts 64 by means of stop collars 66 and the bear-
ing mounts are securely held in place by face plates 68.
-13-
: ~03770~
In operation the photoelectric cell 70, or some other
; suitable sen6ing means, is arranged to detect the presence
at a designated relationship of the first ware row with
respect to the retracted position of frame assembly 44.
Upon detection of such first row the cycle of operation is
initiated resulting in the downward movement of the frame
- assembly so that pusher plates 60 are positioned adja~ent
conveyor 24 and approximately behind the ware in each row
(Fig. 12). Subsequent to such downward movement due to the
activation of fluid cylinders 56, fluid cyclinders 54 are
activated and the assembly is moved forwardly in the direc-
tion of the movement of con~eyor 24. Accordingly, the
ware is engaged by pusher plates 64 and in particular by
the V-notches 72 formed therein tFig. 13). The ware by
;; 15 moving into these notches is oriented longitudinally on
conveyor 24 and due to the forward movement of the assem-
bly is oriented laterally thereon.
After a predetermined degree of forward movement fluid
` cylinders56 are again activated, this time to withdraw or
retract pusher plates 60 to a position above and clear of
the ware. Then, after a dwell period cy~inders 54 withdraw
the assembly to its initial start position. Each cylinder
activation subsequent to initiation of the cycle is pre-
ferably accomplished by microswitches that are mechanically
activated by the moving hardware elements. Other systems
may, however, function equally well.
` It should be noted at this point that each pusher unit
is a wholly separate arrangement which facilitates assembly
and removal thereof from the frame 44. Furthermore, a
-14-
.. .... . . , .................... ~ .
.
lQ37708
dual rod 62 arrangement is employed to: (l) accommodate
the lifting o~ plates 60 in the event such engages a
bottle on the downward movement of the frame and (2) to
. . pre~ent binding in the event of such lifting. Likewise,
S the size of the notches 72 in plates 60 may be varied to
accommodate various bottle sizes and a 40 angle of entry
of such notches is preferred to assist in bottle "roll in".
Another feature of units 58 is the inclusion of shock ab--
. sorbers 74 that are composed of a nylon bushing 76 which
. 10 spaces apart two synthetic 0-rings 78. These of course
.. . reduce noise and vibration as a pusher plate aborts an
. . improper relationship with a bottle and rides off from
that bottle and thus.descends its lowermost position.
After alignment, as is above described, the ware con-
tinues to move forward with conveyor 24 and again its
.~ - presence is se~sed when such is in a proper position for
. "pick-up" by the fluidized bed and bottle transfer mech-
. anism 26.
The fluidized bed and transfer mechanism 26 is best
.. 20 ~ shown in Figs. 2, 3 and 10 and as is evident, is supported . :
. on a vertically adjustable frame 80 by leveling legs 82.
.: The transfer portion 84 of this mechanism is movable be-
. tween three positions (A, B, C) shown in Figs. 2 and 10
and is movable.therebetween by another fluid cylinder
arrange~ent 86 that in turn is responsive to the activa-
tion of a second sensing means 87. However, in the preferred
embodiment of this invention the fluid bed 86 is retained
.~
" .
, .. _ .. . -
1037~0~
in a fixed position on the frame 80 and chuck assembly 88
is movable toward and away from the bed at position B
;` ~Figs. 2 and 10). This reciprocal movement is effected by
means of yet another fluid cylinder arrangement 90 that is
mounted on end plates 92 of the transfer portion.
As may be seen in Fig. 3 the chuck assembly 88 includes
an elongated box-like structure or enclosure including side
: walls 94, end walls 96 and top wall 98. The bottom of this
structure is uncovered but in effect is closured (bottom
walled) by the clamping mechanisms 100 (Fig. 4) that are
positioned along and affixed to supporting rail members
102. The interior of this enclosure is adapted for posi-
tive pressurization by means of fan 104 that forces clean
air through the enclosure and out through various small
bottom wall openings, below described, and principally
through a top wall opening 106. This assures the exclu-
sion of airborne thermoplastic polymer particles from de-
posit on the chuck assembly, which is, of course, a require-
ment if such particles are to be denied entry to the bottle
interior or the deposit thereof on the bottIe finish areas.
The above-mentioned clamping mechanisms 100 include
mounting plates 108 that are positioned along rails 102
in abuting relationship with one another. Each such plate,
in the preferred embodiment also includes a plurality of
laterally extending elongated buide slots 110. Separate
clamping members 112 are slidably positioned in each of
these slots so that the opposite end portions 114 and 116
(Fig. 9) thereof project above and below plate 108, respec-
tively. These members are further comprised of separable
-16-
: ~ .. , . . :
` i~37708
mating clamp segments or jaw mounting blocXs 118 and 120,
that form a split clamp jaw assembly. The segments are
slotted at their approximate midpoint forming a post-like
section to accommodate insertion into the slots and are
retained therein by filler members 122.
Also in the preferred embodiment the lower portions
116 of segments 118 and 120 have separable elements 123
and 125 that are affixed thereto by fastener means, for
example machine screws 124. Furthermore, these lower
portions are recessed to produce cavity 126 that is sized
to accept the bottle finish area 128 and which includes a
surrounding lip 130 that retains and supports bottles when
the segments are mated.
Each segment also has a passageway or conduit 132
extending from the periphery of the cavity through the
upper portion 114 where a suitable connection 134 is
provided for the interconnection of same with a fluid (air)
; purging and cooling gas source (not shown). The peripheral
positioning of conduits 132 assures a good fluid flow along
the walls of the cavity 126 with a bleeding effect between
supported ware and the lip 130 when bottles are being dip-
ped. Although there is no recognized criticality in the
clearance provided between bottle finish 128 and lip 130,
1/32 inches on the diameter is suggested.
- 25 The fluid (air) source mentioned is adapted to provide
varying volumes of fluid to segments 118, 120 during the
cyclic operation thereof. Thus when the segments are
separated a higher volume of air is supplied thereto to
create a cooling condition. This maintains the clamping
:
-17-
:
10377~)8
members at an operating temperature such that the thermal
shocking of ware is precluded as is powder pick-up by the
members. When the segments are mated for bottle retention
a lower volume of air is supplied to purge the ware and
bleed about the lip area 130. Air pressures and tempera-
tures are also not critical to effective operation except
as they relate to meeting the above requirements.
The lower portions 116 of clamping member segments
118, 120 are also beveled as a~ 136 to create a uniform
flow pattern of thermoplastic polymer resin particles and
purging gases around the bottle and clamping member when
such are immersed in the fluid bed. Likewise, lower por-
tions 138 have attached thereto projection means or L-
;~ shaped covers that shield the elongate openings 110 whenthe segments 118 and 120 are mated as shown in Figs. 4,
6 and 9. Shielding as indicated prevents the bottom exit-
; ing of cooling air supplied ~o the enclosure 88 by fan 104
which if allowed to exit there would disrupt the fluid bed
surface 139 (Fig. 9).
To effect the opening and closing of the clamping
members 112 by the movement of separ~able mating clamp seg-
ments 118 and 120 there is provided for each clamping
mechanism 100 two fluid cylinder actuator or activating
means 140. These actuator means are positioned on and
affixed to the top surface of pl~e 108 and thusly are
positioned within enclosure 88. Furthermore, these means
- are connected to the clamp segments by means of piston
rods 142 that engage cross members 144, which members are
connected with selected ones of fol~r supporting rails 146.
-18-
. . . . . . ~, .
~037~0~
Likewise, segments 118 and 120 are affixed to selected
ones of rails 146 so as to move therewith. Accordingly,
the like numbered segments in each row of clamping members
are attached to opposite rails 146 (i.e. the outer rail
on one side and the inner rail on the other side). The
outer ones of such rails 146 are also center supported by
bushing guides 148.
It should be noted here that the shatterproof bottle
coating is applied over the majority of outside bottle
surface area. However, in spite of the fact that the
clamping members 112 are immersed into the fluid bed, it
continues to be desirable to maintain a relatively uniform
and constant bed top surface level. To accomplish this,
the bed may be intermittently fed a predetermined amount
of polymer particle stock after each immersion. Any suit-
able screw or auger, or belt type feeder may be employed
and the point of actual material entry to the bed is op-
tional. Similar, suitable measuring means is employed to
dispense the proper feed stock amount from a proximately
positioned storage container (none of which is shown).
The clamping members 112 will normally be in their
open position until the ware becomes properly positioned
for seizure at position A (Figs. 2 and lO). Then fluid
cylinders 140 will be activated by senser 87 so as to
close the segments 118 and 120 and such will remain closed
about the ware until it is deposited upon conveyor 30.
Multiple clamping devices will, of course~ be employed and
will be synchronized in operation. Further, as is evident
from Figs. 5 and 7, it is preferred that each o~ these
:
-19-
~ . . - . . ~........ . .
1037~
devices grasp at least two spaced rows of bottles at a
time.
After the bottles or ware have been immersed in the
` fluidized bed 86 at position B to accumulate the desired
S resin coating thickness, the transfer mechanism retracts
and removes the bottles therefrom and thereafter reposi-
;~ tions them at ~he third position, C, or deposit point over
the curing oven conveyor 30. Upon reaching this last posi-
tion, the clamping members 112 release the coated ware and
it begins its movement with the noted conveyor through
oven 28. During the passage therethrough, the particulate
resin coating is heated to a molten flowable state to devel-
op a uniform coating and the desired surface texture.
From the foregoing, it should be noted that a unique
process and apparatus is employed in the production of
shatterproof ware. These may, of course, be used in the
preparation of such ware wi~h minor modifications depending
upon the circumstances encountered without departing from
the gist of the concepts herewith disclosed as well as
those which may be considered inherent herein.
-20-
. . -, ~ . .
. ~ . - , . . , . ~, . :
