Apparatus for producing plastic articles with inserts

The present invention relates to a molding apparatus having a first mold half with a core portion and a second mold half with a cavity portion wherein the core portion moves relative to the cavity portion between mold open and mold closed positions. The molding apparatus further includes a carrier plate for receiving molded articles and holding inserts to be incorporated into the molded article. The present invention also relates to transferring the inserts to the mold cores prior to molding.

BACKGROUND OF THE INVENTION 
The present invention relates to an improved apparatus and method for 
removing molded articles from a multi-cavity injection mold and loading 
inserts into the cavity of the same mold. The apparatus and the method of 
the present invention have particular utility in the manufacture of 
laminated plastic containers suitable for holding foods, beverages and 
chemicals. 
The art of molding through, around or adjacent inserts placed in an 
injection molding cavity are well known in the injection molding industry. 
A number of different methods have been developed to load the inserts to 
be included within the molded article and to unload the molded article 
from the machine. Typically, the method that is used for a particular 
molding system takes into account the size, shape and number of the 
inserts to be loaded and such other factors as cost, degree of automation, 
complexity, speed and reliability. 
For example, U.S. Pat. No. 3,837,772 to Van de Walker et al. illustrates a 
top entry robot system which is fed with inserts which are held in place 
on the robot using a vacuum. Upon opening the mold, a transfer plate moves 
into position opposite core pins in the mold. When the transfer plate is 
in this position, the vacuum is substituted by a pressure which forces the 
inserts onto the core pins where they are held in place by a vacuum 
applied to the core pins. If the inserts are open-ended, this vacuum 
method may not be feasible or effective. 
U.S. Pat. No. 4,648,825 to Heil et al. illustrates a different system 
having a horizontal gantry structure which spans perpendicularly across 
the injection machine. An arm which depends from one end of the gantry 
secures a load carrier while another arm depending from the opposite end 
of the gantry secures an unload carrier. The arms move toward each other 
when the mold is opened to perform the loading and unloading functions. 
This approach disadvantageously requires two tooling arms, occupies 
substantial floor space on both sides of the machine, and is very costly. 
European patent document No. 0 357 777 to Orimoto et al. shows a plastic 
mouth insert which is loaded into the injection mold. The purpose of this 
insert is to provide heat resistance in the neck finish area which is 
required during subsequent operations in making a container. As discussed 
in this patent document, it is advantageous to accurately center the 
insert in the cavity and to support it in place as the injected plastic 
flows around it. For the purpose of loading the insert into the injection 
mold, it is recommended to position the insert in place between the mold 
splits, then close the splits in the conventional manner. In some cases, 
it may not be feasible or practical to deliver the insert from the carrier 
plate to its final position in the mold due to space restrictions or 
alignment problems and a co-operative effort from both carrier plate and 
mold are essential. Where molds already employ the use of moving mold 
ejection components, the return stroke of the components can provide the 
double function of insert retrieval, saving redundant motion and time. 
Hence, the loading device should also be capable of working in concert 
with the most advanced molds as previously discussed, which incorporate 
non-rectilinear mold splits motion. 
SUMMARY OF THE INVENTION 
Accordingly, it is a principal object of the present invention to provide 
an improved molding apparatus which uses a single compact carrier plate 
for the loading of mold inserts and the unloading of molded articles. 
It is a further object of the present invention to provide an improved 
molding apparatus as above which mechanically interacts with a carrier 
plate insert loading device to effectively aid in the reception and 
lodgment of an insert in the mold cavity space prior to injection. 
It is still a further object of the present invention to provide an 
improved molding apparatus as above which actively grips and holds or 
contains an insert in the cavity space. 
It is yet a further object of the present invention to provide an improved 
process for molding an article wherein inserts can be more readily 
inserted into the mold cavity and molded articles can be unloaded. 
Still further objects and advantages to the present invention will become 
more apparent from the following description and drawings wherein like 
reference elements depict like elements. 
The foregoing objects and advantages may be readily obtained by the 
improved molding apparatus and process of the present invention. In 
accordance with the present invention, the improved molding apparatus 
includes a first mold half having one or more core portions and a second 
mold half having one or more cavity portions. The first and second mold 
halfs are movable between an open position and a closed position wherein 
said core and cavity portions define at least one space in the shape of 
the article to be molded. The molding apparatus further includes a carrier 
plate for receiving the molded article(s) after the molding cycle has been 
completed and for holding the insert(s) to be incorporated into the molded 
article. The carrier plate is movable from a first position between the 
mold halfs when the mold halfs are in an open position to a second 
position outside of the mold halfs. The carrier plate is also indexable 
between a first position where receptacle(s) for receiving the molded 
article(s) are aligned with the mold core portion(s) and a second position 
wherein means for holding the insert(s) is aligned with the mold core 
portion(s). 
The method of the present invention broadly comprises the steps of 
providing a first mold half having a mold core portion and a second mold 
half having a mold cavity portion; placing at least one insert on said 
mold core portion while said mold halfs are in an open position by 
aligning a carrier plate with means for holding said at least one insert 
with said mold core portion and transferring said at least one insert to 
said mold core portion; withdrawing said carrier plate from between said 
mold halfs; moving said mold halfs so that said mold core portion abuts 
said mold cavity portion; injecting plastic material into a space defined 
by said abutted mold core and mold cavity portions to form at least one 
molded article having at least one insert therein, moving said mold halfs 
to a mold open position, and moving said carrier plate into said position 
between said mold halfs to remove the at least one molded article. 
Further details of the apparatus and method of the present invention are 
discussed in the following description and drawings wherein like reference 
numerals depict like elements.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT(S) 
Referring now to the drawings, FIG. 1 illustrates an apparatus for 
producing plastic articles in accordance with the present invention. The 
apparatus includes a molding machine 10 preferably comprising a 
multicavity machine. The number of cavities and the arrangement thereof 
shown in FIG. 1 are exemplificative only. It should be recognized that any 
convenient number of cavities and any suitable arrangement of the cavities 
may be employed in the machine 10. In fact, one could use a single cavity 
arrangement, although multicavity arrangements are preferred for economic 
reasons. 
The machine 10 includes a first mold half 11 which is a cavity half and a 
second mold half 12 which is a core half. The first mold half 11 has at 
least one cavity 13 therein and preferably a plurality of cavities 13. A 
representative cavity arrangement is shown in FIG. 2. This arrangement has 
two spaced rows of cavities 13 with each row containing eight cavities. 
The second mold half 12 has at least one elongate core 14 therein with the 
number of cores corresponding to the number of cavities. Core(s) 14 are 
each engageable with a respective cavity for seating therein in a 
mold-closed position to form a closed mold for the formation of one or 
more plastic articles therein by injection molding. The number of articles 
formed in an injection molding cycle will depend on the number of cavities 
and corresponding cores. Normally, the core(s) 14 reciprocate from a 
mold-closed position seated in said cavities for the formation of the 
molded articles to a mold-open position spaced from said cavities forming 
a gap between the cores and cavities for ejection of the molded articles. 
FIG. 1 shows the first and second mold portions in a mold open position. 
The mold portions 11 and 12 reciprocate on tie rods 15 and may be powered 
by any convenient motive means known in the art, such as by hydraulic 
cylinder 16, in a predetermined cycle. Molten plastic material is injected 
into a space 76 formed between each core and cavity in the mold-closed 
position by known injection molding procedures. 
It is preferred to retain the formed articles on cores 14 after formation 
of the articles and upon reciprocation of the mold portions from the 
mold-closed position to the mold-open position. A carrier plate 20 is 
provided to receive the molded articles removed from the cores 14. Removal 
of the articles from the cores onto the carrier plate 20 may be 
accomplished by blowing air through vent lines 17 and/or by the use of a 
stripper plate 18 reciprocating on guide pins 19. 
The carrier plate 20 is movable from the outboard position shown in FIGS. 1 
and 2 to a position between the mold halfs 11 and 12. Any suitable 
indexing means 31, 32, 33, 34, 36 and 38 known in the art may be used to 
move the carrier plate 20. One such mechanism is shown in U.S. Pat. No. 
Re. 33,237 to Delfer which is hereby incorporated by reference herein. 
Carrier plate 20 is provided with at least one set of receivers 21 for 
cooling the molded plastic articles. If a longer cooling time in the 
receiver is desired or needed, multiple sets of receivers, such as 
receivers 21 and 22, may be employed. The carrier plate in FIG. 2 includes 
a first set of carrier plate receivers 21 and a second set of carrier 
plate receivers 22. The carrier plate 20 also includes a set of insert 
holders 23, which are positionally arranged in like manner to receivers 21 
and 22. It should be noted that each of sets 21, 22 and 23 corresponds to 
the arrangement of the first mold portion cavities 13, with each of said 
sets being spaced apart by a fixed distance. 
FIG. 3 shows a top view of a carrier plate 20 having two columns or sets 23 
of inserts 44 in alignment with mold cores 14 having a complementary 
configuration. Mold splits 45 mounted to the mold core half 12 are shown 
in a forward extended position. The mold splits 45 are fastened to slides 
46 which move the mold splits 45, and a molded article held by the mold 
splits, axially off a respective core 14. The article is released from the 
grasp of the mold splits through separation of same occurring at a point 
X, toward the end of the ejection stroke. Cams or other mechanical devices 
well known in the art may be employed to dictate the exact distance the 
mold splits will separate from each other and the position at which they 
will separate. 
The carrier plate 20 has one or more mandrels 51 mounted thereto to hold 
insert(s) 44. Each mandrel 51 can be made of a flexible material such as a 
plastic with a hollow core and serrated sides which act as fingers to 
spring against and hold the inside diameter of the insert 44. Each mandrel 
51 is preferably mounted on a structural channel 52 which is fastened to 
and positioned by actuating piston-cylinder unit 53. The piston-cylinder 
unit 53 is used to extend the channel 52 and the mandrel 51 and thereby 
advance the insert 44 to an axial position between the open mold splits 
45. Of course, there are numerous methods for 15 holding an insert on an 
insert holder dependent on its size and shape and how it must interact 
with the cooperating mold components which are to receive the insert. This 
is but one example. 
Adjacent the columns of insert holders 51 are the columns of receiving 
stations 21 and 22 which receive the molded article(s) after ejection. 
Bumper pads 55 are fastened to the structural channel 52 and are sized 
such that their forward face 56 is a prescribed distance from the base of 
the insert 44. As shown in FIG. 4, when the mandrel holding channel 52 
moves forward, the face 56 of the bumper pad 55 hits a corresponding plane 
on the mold split 45. The bumper pad 55 thereby defines the correct axial 
position of the insert between the mold splits. As the actuating cylinder 
53 continues to push forward, the relative axial position of both the 
insert 44 and the mold splits 45 are kept constant. As the mold splits 45 
move inward toward the center axis of a respective core 14, the mold 
splits 45 come together to grip or envelope the insert 44. To this end, 
each mold split 45 has a notch 70 for gripping or receiving a portion 72 
of the insert 44. 
FIG. 5 shows the moment when the insert 44 is first closed upon by the mold 
splits 45. Further movement of the mold splits to their seated position 
effectively strips the insert from the mandrel 51. After the insert has 
been stripped from the mandrel 51, the carrier plate 20 is moved from a 
position where the insert(s) are aligned with the mold core(s) 14 toward 
the outboard position and the mold halfs 11 and 12 are moved toward their 
closed position. 
FIG. 6 shows an insert 44 lodged in its position in the space 76 defined by 
the mold core and cavity prior to injection of the plastic material. FIG. 
6 also shows the manner in which the mold splits 45 are accommodated by 
shaped mold cavity and mold core portions 80, 82. Plastic material is 
injected into the space 76 via nozzle 78. The plastic material flows 
around the insert 44 and incorporates same into the molded article being 
formed. After the plastic material has been cooled and solidified, the 
mold portions 11 and 12 are moved to their open position. During this 
opening operation, the molded article remains on the core 14. After the 
molds have reached the open position, the carrier plate 20 is moved from 
the outboard position to a position intermediate the mold halfs where one 
of the sets of receiving stations is aligned with each mold core(s) 14. 
The slides 46 are then moved toward the carrier plate 20 and the molded 
article is unloaded into one of the receiving stations 21 and 22 mounted 
to the carrier plate 20. The operation of carrier plate 20 in this respect 
is the same as in the aforementioned U.S. Pat. No. Re. 33,237 which is 
again hereby incorporated by reference herein. 
FIG. 7 illustrates an alternative embodiment wherein an insert 57 of 
elongated conical or tubular construction is to be loaded. The insert is 
not held on a mandrel. Instead, it is held in a receptacle 58 which is 
mounted to the structural channel 52. The insert 57 may be held in place 
in receptacle 58 by applying vacuum or other alternate means of retention. 
As described above, the receptacle 58 on the channel 52 moves the insert 
57 to a point where mold splits 45 grasp the insert 57 and remove it from 
the receptacle 58. The mold splits 45 then carry the insert 57 the 
remainder of the distance until it is seated on the core 14. FIG. 8 shows 
the insert 57 lodged in its position in the cavity while the mold is 
closed. 
The operation of the apparatus 10 after molding has been completed is as 
follows. Once the mold is opened, the carrier plate 20 moves into place 
between the mold halves 11 and 12 with the receiving stations 21, 22 
opposite the mold cores 14. The mold splits holding plate 46, commonly 
referred to as a slide, then moves forward with the mold splits 45 toward 
the receiving stations and once the molded article has partially entered 
the receiving station, the mold splits 45 continue to move forward but 
also move apart from each other until the molded article is no longer in 
contact with the mold splits and is fully engaged in a respective 
receiving station. The carrier plate 20 then indexes laterally a short 
distance, enough to move the molded article in the receiving station aside 
from being in axial alignment with the mold core 14 and to position the 
insert 44, 57 to be loaded in direct axial alignment with a respective 
mold core 14. The insert holding means 51, 58 is then extended, with the 
insert 44, 57 toward and over the core 14 until the insert is positioned a 
predetermined distance past the plane of the forward face of the opened 
mold splits. At that point, the insert holding means 51, 52, and 53 
contact the mold splits by way of bumper pad forward face 56 hitting the 
front surface of mold split 45 and together they are pushed by actuating 
cylinder 53 to return the mold splits 45 to the rearward position. As the 
rearward mold splits motion takes place, the mold splits come slowly 
together gripping or enveloping all or part of the insert and are thereby 
interactively removing or receiving the insert from the carrier plate 
insert loading means. The insert holding means 51, 52 and 53 are then 
retracted and the carrier plate 20 is removed to a location outside the 
mold for insert loading onto the carrier plate and molded part unloading, 
as required. With the insert now supported in place by the mold splits, 
the mold is closed and plastic injection is initiated. 
The apparatus of the present invention has numerous advantages associated 
with it. For example, a single device, namely the carrier plate described 
herein, loads the mold with inserts and unloads the completed article from 
the mold. Still further, the carrier plate performs the loading and 
unloading operations from a single face. Still further, the apparatus 
mechanically grips, holds or envelopes an insert in the cavity space. 
Still further, the apparatus lends itself to a method of installing an 
insert into a mold where the mold is dynamically interactive with the 
insertion means of the carrier plate. 
It is apparent that there has been provided in accordance with this 
invention an improved apparatus and method for producing plastic articles 
which fully satisfies the objects, means, and advantages set forth 
hereinbefore. While the invention has been described in combination with 
specific embodiments thereof, it is evident that many alternatives, 
modifications, and variations will be apparent to those skilled in the art 
in light of the forgoing description. Accordingly, it is intended to 
embrace all such alternatives, modifications, and variations as fall 
within the spirit and broad scope of the appended claims.