Note: Descriptions are shown in the official language in which they were submitted.
566
1 Case CD-4540/CD4574
HAN~LED CONTAINERS, PROCESS AND APPARATUS THEREFOR
Field of the Invention
This invention is in the field of containers
fabricated of thermoplastic polymeric materials by the
general technique of forming a parison or prefo~n and
thereafter enlarging the preform by internally applied
gas pressure, or blow molding, while said preform is
within a further mold providing the final desired con-
figuration. More particularly, a new variety of con-
tainer having a handle portion, or handleware, isprovided, as well as improved apparatus and a process
for generating such handleware.
Back~round and Prior Art
The popularity of blow molded handleware of
thermoplastic polymer has grown in recent years as
consumers begin to appreciate the ease of use and the
non-breakable characteristics of such containers.
Handled containers are especially popular in the larger
sizes, i.e. containers having a capacity of one quart
or greater. Exemplary of products which are often
packaged in handleware are starch, bleach, detergent,
milk, distilled water, etc.
In the past a class of blow molding machines
known as the '7inject, extrude and blow" machines have
been adapted to blow mold handled containers of large
size. In these machines the neck, or finish7 of the
container is injection molded in an injection mold
superimposed on an annular orifice~ After the mold
is filled from the orifice, the mold is moved away from
the orifice as the tube integral with the material
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filling the mold is extruded through the orifice. The
blow mold is then closed between the tube and the neck
mold of the orifice pinching the tube shut near the
orifice. Blow air is then injected through ~he neck
mold into the tube, and the tube is simply inflated to
the configuration of the blow mold~ In early attempts
to adopt such injec~ion, extrude and blow machines for
the manufacture of handled containers, it was found
nearly impossible to extrude a tube having both an
integral injection finish and a diameter sufficient to
provide material properly located in the parison to be
pinched shut by the blow mold to form an integral handle
upon blowing. This early attempt at forming handleware
resulted in the production of much waste material, i.e.
flash, which was principally found on the interior and
exterior of the handle. Other problems were also recog-
nized, such as uneven material distribution and pin
holes in the handle.
Further refinements were made on the inject,
extrude and blow process which were claimed to reduce
the amount of flash produced and to also provide a con-
tainer having uniform material distribution. By
reducing the amount of flash which must be trimmed
from the container, leaks in the container are said
to be avoided. Exemplary of these newer machines is
the one disclosed in Uhlig - U.S. patent 3,944,642,
issued 16 March~ 1976.
In the newer version the tubular parison
integral with the injection molded finish portion of the
container is formed in a conventional manner as set
forth in Uhlig~- U.S. patent 3,9~3,199, issued 26 March,
1976. The preform is then preblown in an intermediate
blow mold which has a similar but smaller shape than
the final blow mold. The preblow preform has a portion
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which is of a configuration such that the preform
portion which will form the hancLle will be encompassed
within the handle defining portions of the final blow
mold. Once the preblown preform ls positioned within
the final blow mold the preform is blown to its final
shape. Even though this machine and process produces
a handled container which is free of external flash,
there is still produced flash which is in the interior
of the handle, i.e. in the space encompassed between
the handle and the container.
Handleware may be produced without concurrent
production of flash by the apparatus disclosed in
Adams et al - U.S. patent 3,029,471, issued 17 April,
1962. This apparatus injection forms the handle follow-
ed by formation of an extruded tube which is integralwith the handle. The tube is extruded to a sufficient
length to fill the axial length of an adjacent split
blow mold. The split blow mold is closed to capture
that portion of the extruded tube beneath the injection
molded handle so that that portion of the tube may be
inflated to form the container. Since the apparatus
passes the molten thermoplastic material through a
single orifice for both the injection and extrusion
steps, a highly complex timing and mechanical system
must be used. Furthermore, temperature control of the
injection finish with respect to the extruded tube will
be difficult to handle at best.
Heretofore, no process and apparatus has been
provided whereby the disadvantages and complexities of
the prior art are avoided. The present invention meets
these needs. The process of the invention comprises
injection molding of a thermoplastic preform or parison
including an injection formed handle portion, followed
by a unitary blow molding formation of said parison,
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which operation may include a final orientation configu-
ration of the handle portion as an ancillary function of
the blow molding operation and as is more particularly
described herein. The apparatus of the invention in-
cludes an injection molding station and blow moldingstation and power and transport means generally as
already known, viz., as in Canadian patent application
313,098.
The injection molding station is characterized
in that a split mold is used. The mold portions of the
present inventions include a cavity for receiving and
forming a handle portion generated in the injection
molding operation. After formation of a handled
parison in said split injection mold set, it is then
positioned between the halves of a split blow mold at
a blow molding station, the said blow mold pairs being
characterized in that a handle cavity is provided to
receive the injection molded handle portion. ~oreover,
as is more particularly illustrated hereinafter, said
cavity in preferred embodiments is larger than the
actual injection blow molded handle configuration and
accommodates and forms a final orientation thereof as
a concurrent incident of the blow molding step.
Describing the improved apparatus more fully, it
includes: an injection molding station, for forming a
plastic preform having an integral handle thereon, the
molding station including, (i) a split injection mold
defining a preform cavity with a contiguous injection
molded handle cavity, an injection mold carrier cavity,
and an injection nozzle cavity, the preform cavity being
between the injection mold cavity and the nozzle cavity,
(ii) power means engaged with the split injection mold
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for opening and closing the split injection mold, (iii)
a movable preform pin, (iv) an injection nozzle which
nests into the injection nozzle cavity when the split
injection mold is closed, and (v) injection power means
for injecting, under pressure, thermoplastic material
through the injection nozzle to a preform recess formed
at least partially by said injection mold handle cavity
and by the preform pin being positioned within the pre-
form cavity; a blow molding station having, ~i) a split
blow mold defining a blow mold cavity with a contiguous
blow mold handle cavity and a blow mold carrier cavity,
(ii) power means engaged with the split blow mold for
opening and closing the split blow mold, and (iii) a
movable blow pin, the blow pin supplying pressurized
gas to inflate the preform; moving means for moving a
preform carrier from station to station, the preform
carrier having a portion to achieve attachment of the
preform to the preform carrier when the preform is
formed by the injection of thermoplastic material in
the preform recess and having another portion which is
in mounted relationship with the moving means at the
time the attachment is achieved, and the preform carrier
being (i) receivable into the injection mold carrier
cavity and the blow mold carrier cavity, and (ii) hollow
to allow passage through the preform carrier of the pre-
form pin and to allow nesting of the blow pin in the
preform carrier.
Optionally there may be provided heat treating
stations between the injection molding station and the
blow molding station~ These heat treating stations
would be utilized to either raise, lower or maintain
the temperature of the preform as it moves from the
injection molding station to the blow molding station.
The heat treating stations can also be utilized to
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selectively heat or cool a specific portion o~ the preform
to provide a heat programmed preform to the blow molding
station.
Since the preform is rigidly held by the moving
apparatus as it is moved from the in~ection molding station
throu~h the heat treatment stations to the blow mold station,
the exact location of an~ point on the preform is known.
Locating the injection formed handle within the blow mold
handle cavity is therefore easily achievedO
The apparatus is also highly advantageous in that
it is readily adaptable for producing biaxially oriented
containers. When biaxial orientation is desired the optional
heat treating stations are used to maintain or bring the
injection molded preform to its biaxial orientation
temperature and the blow molding station is provided with a
means for biaxially orienting the container with longitudinal
and radial stretch.
An ejection system is desirably provided for removing
the formed container from the moving apparatus. Such a
system would be located subsequent to the blow molding step
and prior to the injection molding step.
In summary, thereforer the present invention may be
seen as providing, in a hollow thermoplastic container, blow
molded from an injection molded preform, the container being
closed at one end and terminating at the other end in an open
mouth, the improvement comprising the container additionally
having an injection molded handle integral with the container,
the handle being attached at only one point to the container
and being formed contemperaneous with the formation of the
preform.
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The present in~ention may also be seen as providing
a process for molding hollow plastic containers by the steps
of injection molding a thermoplastic preform or a parison in
a split injection mold, cooling the preform to a temperature
at which it will maintain its basic shape~ and therea~ter
inserting the preform in a split blow mold and inflating to
the container shape defined by the blow mold characterized in
that the injection molding step includes the formation of a
solid injection molded handle portion in a cavity contiguous
to the injection mold cavity, and the handle portion is
positioned in a handle cavity provided in the split blow mold,
wnereby the preform is inflated to a shape defined by the
split blow mold including a hollow plastic container having
an injection molded handle.
These and other features of this invention contributing
satisfaction in use and economy in manufacture will be more
- fully understood from the following description o~ a preferred
embodiment of this invention when taken in connection with
the accompanying drawings wherein identical numerals refer to
identical parts and in which:
FIGURE 1 is a top plan view of an apparatus embodiment;
FIGURE 2 is a front elevational view of the injection
molding station-shown in Figure l;
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FIGURE 3 is a sectional view taken through
section lines 3-3 of Figure 2;
FIGURES 4-6 are side partial sectional views
taken through the center line of
the split injection mold shown
in Figure 2;
FIGURE 6A is a broken away front view of the
split injection mold shown in
Figure 2;
FIGURE 6B is a side view of the split
injection mold shown in Figure 2;
FIGURE 7 is a sectional view taken through
section lines 7-7 of Figure 6;
FIGURE 7A is a sectional view taken through
section lines 7a-7a of Figure 4;
FIGURE 8 is a front elevational view of one
of the heating stations shown in
Figure 1 with the heating station
in the down position;
FIGURE 9 is a front elevational view of
the heating station shown in
Figure 8 in the up position;
FIGURE 10 is a sectional view taken through
section lines 10-10 of Figure 8;
FIGURE 11 is a front elevational view of
another heating station shown in
Figure l;
FIGURE 12 is a ~ront elevational view of
the blow molding station sho~n
in Figure l;
FIGURE 13 is a sectional view taken through
section lines 13-13 of Figure 12;
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FIGURES 14-16 are front partial sectional
views taken through the center ~-
axis of split blow mold shown ,~.
in Figure 12; ~;;
FIGURE 17 is a s:ide elevational view
- of the ejection system shown
in Figure l;
FIGURE 18 is a front elevational view
of the ejection system shown ~;
in Figure 17;
FIGURE lg is a perspective view of a ~.
portion of the moving means
shown in Figure 1 and the
attaching mechanism shown in
Figure l; and
FIGURES 20-23 are views of an embodiment of
- a novel handled container as
provided by the apparatus and i.
method. ~`
Referring now to Figure l, there is shown an
apparatus of this invention generally designated by the
numeral 10 which apparatus includes an injection mold-
ing station, generally designated by the numeral 12, a
first heating station, generally designated by the
25 numeral 14, a second heating station, generally desig- ~.
nated by the numeral 16, a blow molding station ;-
generally designated by the numeral 18, and an injection ^.
or removal station, generally designated by the numeral k
20. These various stations are positioned around a
30 moving apparatus generally designated by the numeral 22
which includes a rotating table 600 and an attaching
mechanism, generalIy designated by the numeral 11 for
holding the injection formed preform as it moves through
the various stations. The utilization of the first and
35 second heating stations 14 and 16 are optional. In some
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instances it may be desired that instead of two heating
stations, a heating and cooling station be utilized in
combination. Depending upon the particular thermo-
plastic material being workecl and upon the requirements
needed for the blow molding of this material, it may be
desirable not to utilize any heat treatment stations
which use positive heat addition or removal. In these
instances the preform would be subject only to ambient
air. The particular combination of heat treatment
stations, or the lack of them, is fully within the
discretion of the user of the apparatus of this inven-
tion and the addition or deletion of such stations would
not materially affect the operation of this apparatus.
Blow molding station 18, for the apparatus in
the drawings, can be used for the formation of biaxi-
ally oriented containers. As shown in Figures 14-16, a
push rod may be utilized to guide the pre~orm as it is
blown to achieve simultaneous axial and radial stretch.
It is to be understood that the blow molding station
may also provide conventional blow molding without the
utilization of a stretch rod.
The injection molding station 12 is sho~n in
~igures 2 and 3. As can be`seen from these figures,
injection station 12 has a frame which includes a floor
plate llO and injection molding side plates 108 and 106.
Connecting injection molding side plates 108 and 106 at
a point near their mid height is horizontal tying plate
130. At the upper end of injection molding side plates
108 and 106 there are a pair of upper tying plates 118
which provide tying of plates 108 and 106 together at
that point.
The split injection mold is defined by comple-
mentary cavities in the injection split mold halves lll
and llla. The embodiment illustrated has an injection
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split mold which defines two preform cavi-ties. It is to
be understood however, that single cavity operations or
operations involving more than two cavities are possible
with the apparatus of this invention. To produce the
handleware of this invention the split injection molds
have a cavity defining a main body portion, i.e. pre-
form cavity, and a handle portion as seen in Figure 6~.
Preform pin 124 fits within the preform cavity to pro-
duce a closed end hollow preform~ The handle cavity is
injection filled with thermoplastic material to produce
the handle which is designated "H" in the drawings.
Injection split mold halves 111 and llla are
mounted, respectively, on platens 114 and 117. Pl~ten
114 is a non-moving platen with platen 117 being movable
in a horizontal direction, Movement is achieved by the
utilization of a bank o~ hydraulic cylinders 150, 151,
and 152 which are shown in Figure'l. These hydraulic
cylinders are mounted to horizontal tying plate 130.
To insure aligned movement of platen 117 in the hori-
zontal direction there is provided a plurality of guiderods, One of these'guide rods is shown in Figure 3 and
is labeled with the number 160. Guide rod 160 is
typical of the other guide rods utilized and the de-
scription of it would apply to the other guide rods
utilized. Guide rod 160 is rigidly attached to platen
114 at one of its ends and to stud 169 at its other end
with stud 169 in turn being attached to the underside
of horizontal tying plate 130. Note, as is shown in
Figure 3, guide rod 160 passes through an aperture in
platen 117. The fit of guide rod 160 through this
aperture must be, of course, exact to insure fidelity
of movement of platen 117,
Positioned immediately below injection split
mold halves 111 and ll'la and centered to the two preform
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cavities are two injection nozzles J one for each cavity.
Only one of these nozzles is shown in the drawings, how-
ever a description of it is equally applicable to the
other. Injection nozzle 161 is positioned so that it
enters into an injection nozzle cavity provided in in-
jection split mold halves 111 and llla. Upward and
downward movement of injection nozzle 161 is provided
so that it may move upward into the injection nozzle
cavity and may move downward away from the cavity. In-
jection nozzle 161 is mounted to typing beam 112. Note
that in Figure 1 the injection apparatus utilized to
inject the plastic through the injection nozzle is posi-
tioned adjacent to injection molding station 12 and is
labeled "I". The position and construction of apparatus
"I" is discretionary with the user of the apparatus of
this invention, it being understood that any apparatus
which is capable of injecting hot thermoplastic material
under pressure through the injection nozzles into the
injection mold preform recesses, hereinafter described,
will be suitable for the purposes of this invention.
Immediately above injection split mold halves 111 and
llla there is positioned a pair of preform pins 124 and
124a. Preform pins 124 and 124_ are mounted rigidly to
preform mounting stud 129. Preform mounting stud 129
can be bolted to block 128 so that easy replacement of
preform pins 124 and 124a can be achieved by the mere
unbolting of stud 129 from block 128. On the upper
surface of block 128 there are attached three double
acting hydraulic cylinders 116. These cylinders will
provide upward and downward motion to pins 124 and 124_
so that they may enter the split injection mold and be
removed therefrom when desired. To insure perfect
alignment of preform pins 124 and 124a within split
injection molds during the movement provided by hy-
draulic cylinders 116 there is provided a pair of gear
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tracks 120 and 120a which are connected to injection
molding side plates 108 and 106, respectively. These
gear tracks cooperate with circular gears 122 and 121 to
provide positive movement and thus assure correct align-
ment. Circular gears 122 and 121 are rotatively mounted
to gear axles 122a and 121_, which are in turn carried
by block 128.
Located adjacent the bottom of the injection
split mold half 111 are two mechanisms for severing the
injection tails from each of the preforms formed in the
two preform cavities. These mechanisms are optional and
may not be used in those cases where the downward move-
ment of the injection nozzle breaks the tail from the
preforms. The severing mechanisms are identical and the
description of one is equally applicable to the other.
In Figures 6, 7 and 7A there is shown a severing mech-
anism generally designated by the numeral 180. As can
be seen, this mechanism fits within a recess cut into
the bottom of split injection mold 111. Severing mech-
anism 180 has a block portion 166 with arms 166a and
166b. Mounted on the outside surfaces of arms 166a and
166b are push rods 165 and 164, respectively. Posi-
tioned on the rear surface of arms 166a and 166b are
springs 167 and 168, respectively. Knife 162 is mounted
on the front side of block 166 and as can be seen in
Figures 6 and 7A, knife 162 has a cupped surface 163
which is contoured so that it forms a portion of the
injection mold cavity in injection split mold half 111.
The leading edge of cupped surface 163 is a knife edge
190 which is sharpened to achieve the severing of the
injection tail. In Figure 7~ severing mechanism 180 is
shown in the retracted position with cupped surface 163
forming a portion of the cavity in injection split mold
half 111. In Figure 7 severance mechanism 180 is shown
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in the extended position. As can be appreciated, knife
edge 190 has travelled a path which will enable it to
sever a tail formed in the injection nozzle cavity.
This severing action is depicted in Figure 5 wherein
severing mechanism 180 is in the extended position.
As mentioned previously, injection molding
station 12 is positioned around moving apparatus 22.
Moving apparatus 22 includes a rotating table 600 and a
plurality of attaching mechanisms 11 which are spaced
lQ equiangularly about table 600. For the embodiment shown,
table 600 rotates in a counter-clockwise direction.
Rotation is an interrupted movement with the table stop-
ping rotation when the preform or bottle is registered
before a station. Interrupted rotation is provided by
any one of the many well-known commercial conventional
systems.
The attaching mechanism is attached to the in-
jection molded preform as it is formed at the injection
molding station 12. The mechanism then carried same to
subsequent stations until the final blown article is re-
moved from mechanism 11 at the ejection or removal sta-
tion 20. The attaching mechanisms 11 shown in Figures
1 and 19 are especially adapted for utilization with the
illustrated embodiment of this invention. It is to be
understood that other attaching mechanisms may be uti-
lized to accommodate the peculiarities of other systems
of this invention. It is also obvious that while a
rotating table may have advantages with respect to con-
serving floor space, other moving apparatuses may be
used having different configurations~ For example, the
moving apparatus may provide linear movement of the
attaching mechanisms with the various stations posi-
tioned adjacent thereto in a line.
Reference is directed to Figure 19 wherein a
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detail blo~up of one o~ the attaching mechanisms is de-
picted. Since all of the attaching mechanisms are essen-
tially identical, a description of any one mechanism is
equally applicable to all.
As is shown in Figure 19, attaching mechanism
11 is movably mounted to table 600 by means of left
mounts 602a and 602_ and right mounts 602 and 602c.
Movably held by these mounts are attaching mechanism rods
604 and 604a. At the proximate ends of these rods there
are rod stops (not sho~n) to limit the outward travel of
the rods. At the distal end of rods 604_ and 604 there
is attached thereto plate 608. Between plate 608 and
mounts 602_ and 602c there is provided,~round the rods,
springs 606a and 606 which urge the rods, with attached
plate 608, in a direction outward from the center of
table 600.
Plate 608 has a pair of open-ended pockets for
receipt of a pair of mandrels 24 and 24a to which the
preforms are held as they traveI from the injection mold-
ing station to the remaining stations~ In Figure 19 oneof the two identical pockets is shown and a description
of it is equally applicable to the other pocket. The
exposed pocket in Figure 19 is shown to have a circular
aperture therethrough defined by annular sidewall 616.
~mmediately above annular sidewall 616 is landing area
610 which is dimensioned to receive flange portion 612
of mandrel 24. Assuring further that there is no excess
wobble of mandrel 24 within its pocket there is provided
annular mandrel wall 614 which is dimensioned to nest
within the aperture defined by annular sidewall 616.
Below annular mandrel w~ll 614 there is provided a pair
of intersecting beveled surfaces 618 and 620. These
surfaces resemble two truncated cones which intersect at
their bases and are received in complementary beveled
cavities found in the injection split mold and the blow
split mold as hereinafter described~ By utilizing
beveled surfaces 618 and 620, fidelity of positioning
within the injection and blow mold cavities is achieved
when the injection split molds and the blow split molds
close around a portion of mandrel 24, With the mandrels
captured in the injection split mold, as shown in Figure
4, each mandrel has an annular downward facing surface
621 which will form the uppermost boundary of the recess
into which the thermoplastic material is to be injected
when the preform pins are in place. Immediately below
surface 621 is a mandrel end piece 622 which will hold
the injection formed preform at its neck subsequent to
the injection molding operation. Another function
served by surface 621 is that it, in combination with
the preform pin, forms the inside boundary of the in-
jection mold recess.
The mandrels described above are ones which have
been found to be highly preferred. They also reflect the
finding that it is highly preferential to carry the in-
jection formed preform by its neck as it moves from
station to station. However, other mandrels having
different designs ~hich accomplish the same function as
the above-described mandreIs may, of course, be utilized.
Furthermore, it may be desirable, in some cases, for the
preform to be carried at a point other than at a point
adjacent to the neck portion. For example, a mandrel
could be used whereby the preform is carried at a point
near its midsection. Also it should be realized that
while the mandrels described above carry the preform by
making contact with it on its inside surfaces, it is
fully within the scope of this invention to utilize
mandrels which carry the preform by Making contact on
the preform outside surfaces. For the embodiment shown,
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the preform is held to the mandrel due to the preform
contracting around the mandrel end piece 621 as the pre-
form cools. In those cases where the mandrel would
capture the preform at a point on the preform's outer-
side surfaces, it would be desirable to u-tilize an
interference fit to hold the preform to the mandrel.
The operation of the injection molding station
12 is initiated with the injection split mold in the
open position as is sho~n in Figure 3. Table 600 rotates
and stops so that the mandrels 24 and 24a are positioned
for receipt by the injection split mold when it closes,
as is shown in Figure 4. As injection split mold half
llla moves to close the split mold it will press against
a portion of the beveled surface of mandrel 24 and 24a
urging attaching mechanism 11 towards the center o~ table
600. ~lso as mold half ll'la closes, it presses against
push rods 164 and 165 threby retracting severing mech-
anism 180. The position of severing mechanism 180 in
the retracted position is shown in Figure 7A. After in-
jection split mold half llla has completed its travelthen the preform pins 124 and 124a are lowered through
mandrels 24 and 24a and down into the preform cavity
formed by the injection spl~t molds, cupped surface 161
and annular downward facing surface 621. Note that the
beveled surfaces of mandrels 24a are nested into the
complementary beveled cavities 80 and 80a which are so
labeled in Figure 6. This nesting, as noted be~ore, is
to insure correct registration of the mandrel with re-
spect to the injection split mold cavity formed by the
injection split mold halves. Figure 4 shows the injec-
tion split molds in the closed position with the preform
pins positioned in the cavity and the injection nozzle
cavity 196 (Figure 5) enclosing nozzle 161. Plastic is
injected through'the injection nozzle into the recess
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formed by the injection mold cavities, cupped surface
163, the preform pin and the annular downward facing
surface 621. Plastic will also enter injection mold
handle cavity 198 shown fillecl with plastic in Figure
6A~ From ~igure 6A it is seen that the plastic flows
from the recess to fill handle cavity 198. Subsequent
to the injection of the hot thermoplastic material into
the recess and handle cavity) cooling fluid is passed
through cooling traces 115 and 115a to cool the mold and
thus chill the plastic. After the plastic has chilled
sufficiently the preform pins 124 and 124a are removed
from the preform. To conserve cycle time, the preform
pins are withdrawn from the preform when the preform has
reached a temperature that renders the pre~orm rigid
enough to prevent deformation as the pins are removed.
Also by pulling the pins without waiting for further
cooling, an energy saving is realized as the preform
does not have to be heated back up to its blow molding
or biaxial orientation temperature as the case may be.
After the preform pins have been removed injection split
mold half llla is retracted. Follower rods 164 and 165,
due to the urging of follower rod springs 168 and 167,
follow mold half llla as it opens. This results in
knife edge 190 moving across the injection mold tail to
sever it from preform "P". This severing operation is
depicted in Figure 5. As injection split mold half llla
moves, attaching mechanism 111 will follow for a part of
the total travel of the mold half. Figure 5 shows this
movement. The advantage gained by having attaching
mechanism 11 move outwardly is that the preform will be
spaced sufficiently far enough from the split mold
halves so it can be rotated from the injection molding
station 12 without interference`being encountered.
Distance from split mold half 11`1 is achieved as the
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travel of attaching mechanism 11 is stopped by rod stops
~hile split mold half llla continues to travel. Since
preform "P" is rigidly held by mandrel 24a as it moves
from station to station every point on preform "P" is
easily determined at the subsequent stations. By having
the ability to determine the exact location of every
point on the preform it will be possible to perform very
exact heat programming techniques on the preform which
techniques would not be pcssible if the preform moved
with respect to the moving apparatus.
Depending upon the temperature of the preform as
it leaves the injection molding station, the preform may
either be sent immediately to the blow molding station
or to heat conditioning stations for treatment prior to
reaching the blow molding station. If the preform is at
a temperature above the desired temperature for the blow-
ing procedure then the preform can first be sent to a
heat conditioning station in which the preform is cooled
to the proper temperature. The converse is true if the
preform is to cool. Also the preform can be heat pro-
grammed at the heat conditîoning station. When heat
programming is utilized, one portion of the preform will
be heated or cooled to a different extent than other
portions of the preform. By having differences in heat
content throughout the preform it is possible to control
the extent and rate of stretch at the blow molding sta-
tion. As before mentionedJ since the preforms are held
rigidly by the mandrels 24 and 24a it is possible, at the
heat treating stationsJ to apply heat or apply cooling
to any desired point on the preform with complete assur-
ance that this particular point will be in perfect
orientation when it reaches the blow mold station.
In ~:igures 8-10 there is shown a heatin~ sta-
tion of this inventionJ generally designated by the
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numeral 14. Heating station 14 has side plates 204 and
214 which are tied together at their bottom by tying bar
202. Also connecting side plates 204 and 214 is mount-
ing plate 206. Mounting plate 206 has attached to its
front face double acting hydraulic cylinder 208 which is
connected to heating element pedestal 210. Hydraulic
cylinder 208 will provide the power for raising and
lowering heating element pedestal 210. To aid in assur-
ing that pedestal 210 travels in a perpendicular direc-
tion to the horizon there are provided guide rods 216and 21`6a which are attached to the underside of pedestal
210. Guide rods 216 and 216a pass through guide collars
218 and 21`8a, respectively, which collars are attached
to mounting plate 206. Heating elements 212 and 212a
are attached to heating element pedestal 210 by means
of bolts 234 and 234a and plates 254, 250, 254a and 250a
in the manner shown in Figures 8, 9 and 10.
Heating elements 212 and 212a can be any type of
heating element capable of supplying heat to preforms
"P". Preferentially heat~ng elements 212 and 212a will
be banks of electrical heating coils. As mentioned pre-
viously, it may be desirable to cool preforms "P" prior
to their arrival at the blow molding station. If this
is the case, then heating eIements 212 and 212a would be
replaced with cooling elements which might comprise hol-
low collars with forced air being blown therethrough
onto the preform.
In operation heating station 14 is the paragon
of simplicity. Preforms "P" are brought into position
above first heating station 14 from the injection mold-
ing station 12. Once the preforms have come to a full
stop double acting hydraulic cylinder 208 is activated
to raise heating eIements 212 and 212a so that they each
surround their respective preform "P". The heating
~ . :
~:~5~ 6
elements are held in this position as long as needed to
achieve the degree of heating desired. A~ter pre~orms
"P" have reached the desired heat level double acting
hydraulic cylinder 208 lowers the heating elements ~rom
around the preforms. The lowered position is shown in
Figure 8 while the fully raised position is shown in
Figure 9. After the heating elements have been brought
to the lowered position, the preforms are free to con-
tinue their movement towards second heating station 16
upon rotation of table 600.
In Figure 11 there is depicted a second heating
station 16. This heating station is typical of one
which may be utilized to heat program the preform. Note
that the heating elements 330 and 330a only surround the
upper portion of the preforms "P" to provide selective
heating. These heating elements may be of the same type
used at station 14, i.e., electrical heating coi1s~
Second heating station 16 has two side plates 304 and
314 which are tied at their bottom by tying bar 302.
Also connecting side plates 304 and 314 together is
mounting plate 306. Attached to mounting plate 306 is
double acting hydraulic cylinder 308 which is connected
to heating element pedestal 310. Guide rods 316 and
316a which are attached to the underside of heating ped-
estal 310 pass through guide collars 318 and 318a which
collars are attached to mounting plate 306. Double act-
ing hydraulic cylinder 308 is utilized to raise and
lower heating element pedestal 310 while guide rods 316
and 316a, in conjunction with guide collars 318 and
318a, assure perpendicular motion of heating element
plates 332 and 332a, respectively, with these plates
being secured by bolts 334 and 334a. As is the case
with first heating station 14, the preforms "P" are
brought into position above heating elements 330 and
~ ~ 5 ~ ~ 6
330a with the heating element pedestal 310 in the
lowered position. Once preforms "P" are in position,
double acting pneumatic cylinder 308 raises heating
element pedestal 310 so that heating elements 330 and
330a are in proper position around preforms "P". After
the necessary heating has been accomplished double act-
ing hydraulic cylinder 308 is activated to lower heating
pedestal 310 thus removing heating elements 330 and 330a
from around preforms "P" so that these preforms may be
sent to the next station without interference with the
heating elements.
As is the case with station 14, station 16 can
be used to cool the preforms "P" or alternatively, it
may be used to apply heat longitudinally to two sides
of the preform with strip heaters thereby heat program-
ming the preform so that it may be blown to a container
which is eIliptical in cross section and so that the
container has improved uniformity of wall thickness.
As can be seen in Figure 1, there is provided
space for an additional station between second heating
station 16 and blow molding station 18. An additional
heating or cooling station may be utilized at this point
as the need arises.
After the preforms have been heat treated they
are in condition for receipt by the blow molding station
18. As mentioned previously, blow molding station 18
may be one in which the heat treated preforms are blown
without biaxial orientation or with biaxial orientation.
The station depicted in Figures 12-16 is one in which
either type of blow forming of tl~e container can be
practiced.
Blow molding station 18 has a frame which in-
cludes side plates 412 and 412a which are connected to
floor plate 414 at their lower ends. ~lso tying side
~.~ 5 ~ S~ ~
plates 412 and 412a together are mounting stud 418,
upper mounting plate 420 and lower mounting plate 416.
Lower mounting plate 416 has, at its end closest to
table 600, front platen 422 which is rigidly attached
thereto. At its other end, lower mounting plate 416
has rigidly attached thereto bracket 434. Connecting
front platen 422 with bracket 434 are blow molding
guide rods 424 and 424a. These rods pass through guide
sleeves which are made a part of rear platen 430. One
of the guide sleeves, guide sleeve 432, is shown in
Figure 13 and is identical to the guide sleeve around
blow molding guide rod 424. Connected to the inside
face of front platen 422 is a split blow mold half 410.
Connected to the inside face of back platen 430 is the
other split blow mold half 408~ Each of these halves
has a pair of cavities cut therein which cavities to-
gether form a pair of blow mold cavities for blow
for~ing the preform to yield the final container. The
number of cavities found in the blow split molds should
correspond to the number of preforms which will arrive
at the blow molding station. As shown in Figure 14 and
15, the blow mold cavities, I'C", define the shape of the
bottle to which the preform is blown. In addition, each
cavity has contiguous therewith a handle cavity "HC".
Handle cavity "HC" is larger than handle "H" so that
handle "H" has room to move as preform "P" is blown.
This movement is illustrated sequentially in Figures
14-16. In Figure 14 handle "H" is at its nearest point
to the center axis of preform "P". As preform ~Ip~l ex-
pands, handle "H" moves outwardly as seen in Figure 15.Handle cavity "HC" is of a size to let handle "H" move
without interference throughout the blow cycle as is
shown in Figure 16 wherein handle "H" has moved to its
fartherest e~tent. Handle cavity "HC" does not need to
:~ :
~s~
be larger than handle "H" if~ due to infla~ion, handle
"H" does not move. This latter case would arise, for
example, if the bottle neck was the same diameter as the
preform.
Horizontal movement of split mold half 408 is
accomplished by the utilization of double acting hy- .
draulic cylinder 436 which is mounted to upper mounting
plate 420 and the outside face of rear platen 430. By
having rear platen 430 slidably mounted to blow mold
guide rods 424 and 424a true horizontal movement of
split blow mold half 408 is achieved for perfect match-
ing with split blow mold half 410.
Above the two cavities defined by split blow
mold halves 408 and 410 are blow pins 428 and 428a.
These blow pins are provided with vertical movement so
that they may enter into the hollow portion of the
mandrels which are a part of attaching mechanism 11.
This vertical motion is made possible by way of double
acting hydraulic cylinders 426 and 426a. Double acting
hydraulic cylinders 426 and 426a also provide the power
required to raise and lower stretch rod 429 which is
shown in Figures 14-16.
Figures 14-16 depict blowing of bottle "B" from
preform "P". In operation, the table rotates and stops
with the preforms being positioned between split blow
mold halves 408 and 410. Split blow mold half 408 is
moved forward towards the table to close the split blow
molds and, in this traveI, engages a portion of beveled
surfaces 618 and 620 within the blow mold carrier cavity
thereby pushing attaching mechanism 11 until split blow
mold halves 410 and 408 completely encircle beveled
surfaces 618 and 620. The handled preforms are now
centered and positioned within the cavity formed by the
split blow mold halves~ Next, blow pin 428 is
.
~.~5~66
24
introduced through the opening end of mandrel 24 and
seated therein. Once blow pin 428 has been seated,
stretch rod 429 is lowered until it makes contact with
the bottom of the preform. Once contact has been made,
blow fluid is introduced through blow pin 428 to begin
inflation of preform "P". Simultaneously stretch rod
429 moves towards the bottom of the cavity formed by
split blow mold halves 410 and 408 as is shown in
Figure 15. Simultaneous axial and radial stretch re-
sults in the container being biaxially oriented andblo~n to conform to the blow mold cavity as is shown
in Figure 16.
The operation of blow pin 428a is identical to
the operatîon of blow pin 428 and thus the description
of the latter blow pin operation is equally applicable
to the former blow pin.
Once the preform has been blown to form bottle
"B" cooling fluid is passed through cooling traces 431
and 431a to cool the blown container. Once sufficient
cooling has been achieved to insure that the container
is rigid enough so that support from the blow mold
cavity is no longer required, rod 429 is retracted and
blow pin 428 is raised clear of mandrel 24. Double act-
ing hydraulic cylinder 436 is activated pulling split
blow mold half 408 away from split blow mold half 410.
The blown container which is still mounted to mandrel
24 will follow split blow mold half 408 for a short
distance due to the action of follower rod springs 606
and 606a. Once attaching apparatus 11 has traveled its
full extent~ split blow mold half 408 continues to
travel away from split blow mold half 410 until a gap
of sufficient dimension is achieved between the two
split blow mold halves to permit free movement of con-
tainers "B" when table 600 rotates to the next station.
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~-~s~s~
It is to be understood that biaxial orientation
can also be achieved by stretching of preform "P" with
stretch rod 429 to achieve an axial stretch and then sub-
sequently utilizing blow air to inflate the preform to
conform to the cavity formed by split blow mold halves
410 and 408.
To achieve blow molding without biaxial orien-
tation the procedure described above is followed except
that stretch rod 429 is left in the retracted position
and is not activated at all. Thus blow fluid is intro-
duced through blow pin 428 without benefit of the axial
stretch provided by stretch rod 429.
Removal of bottles "B" from mandrels 24 and 24a
is automatically achieved by the utilization of ejection
station 20 which is shown in Figures 17 and 18. As can
be seen ejection station 20 has a pair of upstanding
legs 520 and 520a. Joining these legs together at a
point near their bottom are studs 522 and 522a which
are bolted together as shown in Figure 17. Mounted on
studs 522 and 522a is double acting hydraulic cylinder
524. Double acting hydraulic cylinder 524 has its rod
end connected to block 528. Providing more support for
legs 520 and 52`0a is support member 526 whîch may be
tied into a reinforced concrete bulkhead or the like.
As mentioned above, double acting hydraulic cylinder524 is attached to block 528, Block 528 is slidably
mounted on legs 520 and 520a and will move upward and
downward along these legs in response to the action of
double acting hydraulic cylinder 524. A recess is pro-
vided in block 528 for holding a second double actinghydraulic cy:Linder 530. Second double acting hydraulic
cylinder 530 is attached to bracket 547 which in turn
is attached to slide 532, Second double acting hy-
draulic cylinder 530 will move slide 532 back and forth
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26
along a horizontal plane. SLide 532 is trapezoidal in
cross-section and fits within a trapezoidal cut in guide
block 534. Guide block 534 therefore assures proper
horizontal motion of slide 532 and helps support slide
532 throughout its travel. Attached to the top of
slide 532 is knockoff plate 536. Knockoff plate 536
has two semicircular cuts made therein, 542 and 542a,
which allow knockoff plate 536 to move around the necks
of bottles "B" so that interference between knockoff
plate 536 and the bottles "B" will occur when knockoff
plate 536 is moved downward in a vertical direction.
Holding knockoff plate 536 to slide 532 is accomplished
by bolting attaching plate 537 over knockoff plate 536
and to slide 532.
To provide support for attaching mechanism 11
there are provided support rollers 540 and 540a.
Support roller 540a is rotatably carried by roller
mount 538a while support roller 540 is carried by
roller moun~ 538. As can be seen in Figures 17 and 18,
support rollers 540a and 540 contact plate 608 to pro-
vide resistance to deflection of attaching member 11
when knockoff plate 536 is lowered and brought into con-
tact with bottles "B" to remove them from mandrels 24
and 24a.
In operation, bottles "B" are brought from blow
molding station 18 to a position in front of ejection
station 20. Knockoff plate 536 is in a retracted and
uppermost position. After bottles "B" are in proper
registration with ejection station 20, second double
acting hydraulic cylinder 530 is activated causing
slide 532 to move away from table 600 and thus bring
knockoff plate 536 into position so that semicircular
cuts 542a and 542 are`about the neck portion of bottles
"B". Consequently, double acting hydraulic cylinder
~.~5~5~
524 is activated bringing block 528 downward causing
knockoff plate 536 to likewise move downward and en-
gage bottles "B" and knock them from mandrels 24 and
24a After bottles "B7' have been so removed, hydraulic
cylinder 524 is activated thereby bringing knockoff
plate 536 to its uppermost position. Also second double
acting hydraulic cylinder 530 is activated to cause
knockoff plate 536 to be retracted.
With the ejection station 20 in this position,
table 600 is rotated to the next station which is in-
jection molding station 12 so that the process can
again be repeated.
Timing of the rotation of table 600 and the
activation of the various stations is accomplished by
utilizing well known techniques which are familiar to
those skilled in the art. Most systems will utilize a
combination of electrical switches and photoelectric
sensors as activating and sensing hardware. The res-
idence time spent at any one station by attaching
mechanism 11 will be determined by the time required
by the slowest station. Generally speaking, the
slowest station is injection station 12, however, any
of the other stations ma~ require more time depending
upon the particular requirements of the user of the
apparatus of this invention. If injection molding
station 12 requires the longest residence time, then
the other stations will simply achieve their desig-
nated purpose and will be waiting for rotation of table
600 when the injection forming is accomplished.
Having described the contribution in its pro-
cess and apparatus expression, attention is directed
to Figures 20 24, inclusive illustrating in more detai.l
the novel container as can be generated using ~he
apparatus and method, said container being also
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s
28
indicated in part in Figures 16-1~, inclusive.
FIGURE 20 is a front elevational view
of such a container;
~IGURE 21 is a top plan view of the
container shown in Figure 20;
FIGU~E 22 is a right side elevational
view of the container shown
in Figure 20;
FIGURE 23 is a bottom plan view of the
container shown in Figure 20; and
FIGURE 24 is a sectional view taken through
section lines 20-20 in Figure 1.
This container, generally designated as 30 in-
cludes the handle 44, injection formed as already
described. It is integral with the container 30 being
attached at a single locus to the upper part of the neck
34. Immediately above are helical threads 42 to cooper-
ate with threads in a closure, not shown. A body
portion 36 is closed at its lower end by bottom wall
32. An annular step-out wall segment 3~ provides an
attractive appearance.
The handle 44 as shown has an I beam configu-
ration as further shown in cross-section by ~igure 24.
Other configuration can be utilized provided that a
handle has adequate strength for the function needed.
With the I-beam sectional configuration, parallel
walls 46 and 48 are joined by a web portion 50,
It will be recognized by those skilled in the
art that various weIl known thermoplastic polymers can
be employed in fabricating the handled containers
disclosed herein and using the method and apparatus
disclosed~ Exemplary of such lcnown materials are poly-
ethylene terephthalate, polypropylene~ polyvinyl
chloride and other known polymer materials.
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