Note: Descriptions are shown in the official language in which they were submitted.
`
~()37709
This invention relates to an improved process and apparatus for
coating articles of manufacture and more particularly concerns the pro-
duction of shatter-resistant glassware (i. e., bottleware)O 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 coatings and tech-
niques for the application of same to glassware, 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 subject 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
characteristicsO These have served well in providing the intended protection
in preserving glassware integrity. However, such cannot and do not render
ware "shatter-resistant" or substantially change the fragmentation character-
istics of ware that is broken while under internal pressure.
In the latter respect, it should also be recognized that certain
. glassware, particularly glass aerosol containers, have been provided with
polymeric protective sheaths. These are indicated to be resistive to glass
fragmentation 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, Likewise, 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 pri-
marily to those containerization areas employing internal pressurization
where known aerosol bottle coating techniques are inapplicable. These are
~æ
: . ~ ~ ' .' ~'
~ 037~a~
.
principally considered to be carbonated beverage bottles and the like which,
of course, due to their pressurized state, are subject to severe fragmenta-
tion 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 fragmentation.
Techniques and apparatus for the application of coatings to con-
tainers as are here disclosed establish that certain adhesive characteristics
between the glass and polymer envelope dictate the acceptability and appli-
10 cability for creation of the "shatter-resistant" container desired. Similarly,
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 transparency acceptable to the bottling trade.
The invention contemplates use of thermoplastic polymers as the
"shatter-resistant" coating, for example polyethylene polymers and co-
polymers have been found to be quite satisfactory for use in the process.
The coating process employing such particulate resins dictates that careful
~ .
20 controls on glassware preheat and curing temperatures, immersion times
and the like be maintained to assure production of a properly adherent
coating. It is also preferred that the polymer coating be applied to the ware
using fluidized bed techniques which, in conjunction with the heating, etc.,
referred to may be operated as a continuous line, optionally in concert
with typical bottle forming machinery.
In addition, particular apparatus developments and improvements
have also contributed to the success of the overall process and coated
"shatter-resistant~' bottle product. Unique ware orientation and an improved
chuck assembly are employed to present the ware to the coating medium.
30 Further, and in conjunction with the chuck assembly employed during actual
particulate polymer, coating, improved clamping mechanisms are employed.
-- 2 --
1037~09
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 move-
ment without the adherence or an accumulation of resin thereto.
Prior clamping devices used in conjunction with apparatus of this
type, have adapted for positioning in close proximity only with the fluidized
bed surface. Accordingly, the degree of bottle immersion was dependent
UpOD. the bed surface characteristics around each such bottle. 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.
. .. ~. . .
Immersion 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
20 during dipping .
Hereinabove and throughout the specification and claims reference
is made to a thermoplastic "shatter-resistant" coating. It should be under-
stood that this terminology is employed in the same sense as would phrase-
ology such as shatter proof or immune from substantial fragmentation.
More particularly, 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
30 by design and definition will substantially minimize bottle fragmentation in
the event of such a pressuri:~ed bottle failure.
` 1037'~0~
Thus, in accordance with the present teachings, there is provided
a chuck assembly which may be used in an article coating environment and
which is adapted to grasp a plurality of articles. The assembly which is
responsive to signal indicia includes an enclosure having a bottom wall
structure with a plurality of elongated openings therein, actuator means and
movable support rails which are mounted inside of the enclosure with the
actuator means being rigidly affixed thereto. Jaw mounting blocks are
~;~ provided interconnected to the rails and extending through the opening and
clamp jaw members are present having recesses therein, such being posi-
10 tioned on a portion of the blocks extending through the openings.
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 abrasions, considerable reduction in bottling
and filling line noise, and enable shipping carton redesign without partitions.
Additional objectives andadvantages not enumeratedwill, however,
also becGme more apparent upon continued reference to the specification,
claims and drawing wherein:
Fig. 1 is a top plan view of typical bottle coating line as employs
the immersible fluidized bed dipping apparatus;
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 of chuck assemblies mounted thereto;
' Fig. 5 is a partial elevational cross-sectional view of the dipper
assembly taken along line 5-5 of Fig. 4 and also exposing an end elevation
of a single chuck assembly;
Fig. 6, appearing on the page containing Fig. 4, is a side eleva-
tional view of a chuck assembly in its closed position;
-- 4 --
-
1037709
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;
- - Fig. 10 is a side elevational view showing the fluidized bed dipping
assembly and combined bottle orientation device;
Fig. 11 is a partial front elevational view of the bottle orientation
10 device taken along line 11-11 of Fig. 10;
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 touchness along
20 with the capability of substantial elongation when subjected to sudden or
instantaneous loading 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
30 coating itself will fragment in a reaction similar to that of the glass substrate, -
and, if insufficient adhesion is achieved once the coating fails (i.e., splits
1037709
or otherwise opens), glass fragments will be propelled through the opening,
out and away from the polymer envelope.
Various polyethylene polymers, copolymers and the like will meet
these criteria. It should be recogni~ed 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 "shatter-resistant" coating to bottle-
10 ware include a preheat cycle, a particulate coating application and a coatingcuring or fusing procedure. These basic steps as outlined have, of course,
been employed in numerous coating applications, however, as applied to the
shatterproofing of glassware several specific modifications thereof in the
form of specific resin formulations and time/temperature relationships effect
- the desired end results. Likewise, it should also be apparent that the three
basic steps may be expanded or incorporated with typical glass forming
processes now practiced so that a newly formed bottle may proceed directly
to and through the various required coating steps.
Further, in the event certain glass or resin compositions require,
20 a priming step may be employed to achieve the desired degree of adhesion
between these components. This, it should, however, be understood, is not
contemplated as a required procedure in the preferred form of the invention.
Various primers including silicone emulsions and chromic and polyacrylic
solutions have been 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 lubricant 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 slipperiness to the
30 surface thereby reducing the coefficient of friction of the resinous material
and enhancing the flow characteristics of the finished bottles during further
la377~
handling. Several waxes have been found to be particularly effective and
include those having a silicone-wax composition, 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 sufficient and thereafter labels may be
applied using any of several glues including jelly-gums, casein glues and
acetate adhesives.
The overall apparatus arrangement or combination used in effectua-
tion of the indicated process include- (1) a bare bottle uncaser 10, a box
10 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 dipping mechanism 26, and curing oven 28 and conveyor 30;
and (4) cooling section 32, waxer 34, flame sensitizer 36 and automatic
inspection station 38.
In the instant process, the ware moves with the preheat wire mesh
oven conveyor or conveying assembly 24 into and through the gas fired pre-
` heat oven 22. Within this oven the bottles are brought to a relatively uniform
temperature of between about 400F and 600F which can be accomplished
20 with about 12 minutes' exposure from a cold start. It should be appreciatedthough 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 atticle orientation mechanism 40 and the fluidized bed
coating apparatus and transfer 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 a preferred embodiment, it is contemplated that the bottle coating
30 will be applied by consecutively dipping plural units of preheated ware into
a fluidized bed of particulate resinous material as is above described. It
- 7 -
~ :~ 1037~09
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 bottleO 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.
As alluded to above the parting line cut-off problem is created by
the non-uniformity of the fluid bed surface during bottle imnnersion. How-
ever, immersion of the clamping assemblies creates additional problems
10 hitherto considered 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 assemblies thereofi (2) the bottles being at elevated tempera-
tures, between 400F and 600F, necessarily will conductively and con-
vectively heat the clamping mechanisms thus also sensiti7ing them for
acceptance of the polymer coating, an obviously unacceptable condition; and,
(3) a purging medium 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, has deposited on it hot,
exteriorly coated ware that is incompletely fusedO Such conveyor thus passes
through a fusing or curing zone or oven 28 (gas fired) and onto a circulating
air cooling section or 2:one 32. Again, it should be appreciated that curing
or fusing oven temperatures contribute significantly to the final product
- 30 characteristics and that 450F to 600F represents an acceptable tempera-
ture gradient. Preferably, however retention of the coated ware at a 450F
1(;~3770~
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
tr~ fer~e~
tr~nsf~o~1 into a single line configuration for passage through lubrication
apparatus or waxer 34, on to the flame sensiti~7er 36 and through the inspec-
tion station 38.
A better appreciation of the several apparatus elements and im-
provements above-mentioned, may be obtained by reference to Figs. 2-13.
For example, the bottle or article orientation mechanism 40 may be seen in
10 more detail in Figs. 10-13. Such orienter, as is best seen in Figo 10,
extends across and above the conveyor 24 and is in relatively 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 and one or more
rows of bottles are realigned on conveyor 24 so that they can be properly
grasped at the mentioned pickup point.
The orientation mechanism 40 includes a supporting structure 42
that is affixed either to the frame of conveyor 24 or to others of the associated
apparatus fixtures. Within such structure is pivotally mounted a frame
20 assembly 44 including end members 46 and cross pieces 48. Depending
upon the conveyor width traversed it may also be necessary to reinforce at
least one such cross piece as 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 oscillated 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 420 Like-
wise, the frame assembly is linked with the bearing supports through another
set of fluid cylinders or second actuating means 56 that are adapted to
30 vertically adjust the height of such assembly during the operational cycle
of the apparatus, which is more fully described hereinafter.
1~37~
Cross-pieces 48 have affixed, preferably to both sides thereof, a .
; plurality of pusher units 58. ~ccordingly, 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
on the 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 bearing mounts are securely held in place by face plates 68.
In operation the photoelectric cell 70, or some other suitable
sensing means, is arranged to detect the presence at a designated relation-
ship 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 adjacent conveyor 24 and approximately
behind the ware in each row (Fig. 12). Subsequent to such downward move-
ment due to the activation of fluid cylinders 56, fluid cylinders 54 are
activated and the assembly is moved forwardly in the direction of movement
of conveyor 24. Accordingly, the ware is engaged by pusher plates 64 and
in particular by the V-notches 72 formed therein (Fig. 13). The ware by
moving into these notches is oriented longitudinally on conveyor 24 and due
to the forward movement of the assembly is oriented laterally thereon.
After a predetermined degree of forward movement fluid cylinders
56 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 cylinders
54 withdraw the assembly to its initial start position. Each cylinder activa-
tion subsequent to initiation of the cycle is preferably accomplished by -~
microswitches that are mechanically activated by the moving hardware
elements. Cther systems may, however, function equally well.
- 10 -
.
. ' ' ~ . . :
,
. .
-
'' ' 1037'~0~ ~,
; 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 dual rod 6Z arrangement is employed to:
(1) accommodate the lifting of plates 60 in the event such engages a bottle on
the downward movement of the frame and (2) to prevent binding in the event
of such lifting. Likewise, 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 absorbers 74 that are composed of a nylon
10 bushing 76 which spaces apart two synthetic O-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
po s ition .
After alignment, as is above described, the ware continues to move
forward with conveyor 24 and again its presence is sensed when such is in
a proper position for "pick-up" by the fluidized bed and bottle transfer -
mechanism 26.
The fluidized bed and transfer mechanism 26is best 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 between three positions (A, B, C) shown in Figso 2 and 10 and is
movable therebetween by another fluid cylinder arrangement 86 that in turn
is responsive to the activation of a second sensing means 87. However, in
the preferred embodiment of this invention the fluid bed 86 is retained 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
. . ~ .
. .
1~37qO9
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 positive 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 106O This assures the exclusion of airborne thermoplastic
polymer particles from deposit on the chuck assembly, which is, of course,
. a requirement if such particles are to be denied entry to the bottle interior
or the deposit thereof on the bottle 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 guide slots 110. Separate clamp-
ing 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, respectively. These members are further comprised of
separable mating clamp segments or jaw mounting blocks 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
20 into the slots and are retained therein by filler members 122.
Also in the preferred embodiment the lower portions 116 of seg-
ments 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)
30 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
':,
10377~9
a bleeding effect between supported ware and the lip 130 when bottles are
being dipped. 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.
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 conditionO This maintains the clamping 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 temperatures 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, lZ0 are
also beveled as at 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 portions
138 have attached thereto projection means or L-shaped covers that shield
the elongate openings 110 when the segments 118 and 120 are mated as shown
in Figs. 4, 6 and 9. Shielding as indicated prevents the bottom exiting of
cooling air supplied to 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 separable mating clamp segments 118 and 120 there is
provided for each clamping mechanism 100 two fluid cylinder actuator or
acti~ting ~nean~ 14~). Thede actuator means are po~tioned on alld
af~xed to the top surface of plate 108 and thusly are positioned within
enclosure 88. Furthermore, these means are connected to the clamp
30 segments by means of piston rods 142 that engage cross members 144,
which members are connected with selected ones of four supporting rails 146.
Likewise, segments 118 and 120 are affixed to selected ones of rails 146 so
- 13 -
,. : ~ . . :
.
10377~)9
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
10 a predetermined amount of polymer particle stock after each immersion.
Any suitable screw or auger, or belt type feeder may be employed and the
point of actual material entry to the bed is optional. 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 10). 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 of these 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 resin coating thickness, the
- ~ transfer mechanism retracts and removes the bottles therefrom and there-
after repositions them at the third position, C, or deposit point over the
curing oven conveyor 30. Upon reaching this last position, 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
- 30 particulate resin coating is heated to a molten flowable state to develop a
uniform coating and the desired surface texture.
, ~ .
- 14 -
1(~37~ J9
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 with 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.
.
; : '
'
,. .
,
~',' , .
,: .
~ ZO
; ~'
' ~ ~
, :~
