JPS6316251B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a technique for blow molding from a parison an article of organic plastic material whose properties can be improved by orientation, and whose main purpose is to control the temperature of the parison. It is characterized by the fact that very rapid operating cycles are possible and the steps of parison production, stretchorientation and circumferential orientation can be carried out in a single continuous and yet completely controlled sequence. and an improved oriented hollow article.

Prior art, such as U.S. Pat. No. 3,349,155 and Reissue No. 27,104, teaches methods and apparatus for obtaining blow-molded articles of organic plastic material from parisons. Generally, these methods involve molding a parison over a blow molded core in a parison mold, placing the molded parison and blow molded core in a blow mold, and expanding the parison in the blow mold by fluid pressure. characterized by

Blow molding operations tend to impart an orientation to the product, but such orientation is primarily circumferential;
That is, it is not biaxial. Furthermore, the degree of such orientation is difficult to control. Therefore, it is difficult to obtain advantageous properties in articles capable of biaxial orientation.

It is known that the adjustment of orientation is highly dependent on the adjustment of the temperature of the parison immediately before orientation. Such temperature adjustment is effected by means of heating means which, prior to the orientation step, impart a temperature corresponding to the degree of deformation of the region of the parison to be deformed, preferably by contact with the corresponding surface of the parison. This is best done by surrounding the item with

However, prior art devices for obtaining the desired biaxial orientation are often cumbersome, slow, and inconvenient to operate. Also, the manufacturing speed using such equipment is far less than optimal.

In accordance with the present invention, an improved, controlled, high speed method that maintains substantially consistent article temperature control prior to orientation and/or final expansion while also having less influence on the temperature of the parison. An apparatus for manufacturing hollow articles is provided that obtains an injection blow molding or stretch blow molding sequence of operating cycles.

The device of the present invention comprises: a first core and a first mold that are spaced apart from each other and that are engageable with each other;
means for providing a parison on the first core at a location spaced apart from a location in which the first core and the first mold are mutually engageable; and cooperating with the first core; and the parison to the first
means for placing the parison in the first mold in cooperation with the first core while holding the parison in the first mold to adjust the temperature of the parison;
means for separating from the core; a second core and a second mold spaced apart from the first core and mold, respectively, wherein the second core engages and disengages the second mold; reciprocating, and the second mold is stationary; engaging the second core and a first mold holding the parison at a position spaced apart from the second mold, thereby means for moving the second core and the parison retained therein into engagement with the second mold at a position spaced apart from the first mold;
Means is provided for cooperating with the core to expand the parison on the second core within the second mold to form a finished product.

Preferably, the device includes a product removal plug for removing the finished product in integral spaced relation, preferably laterally spaced relation, to the second core, so that the second When the core engages the parison in the first mold, the ejection plug engages the finished product in the second mold.

According to the device of the invention, the parison wall is formed, for example, by conforming the parison in the first mold to the shape of the first mold, e.g. by expansion.
Close surface contact can be established with the wall of the first type. The shape of the parison can be chosen such that the second core can be inserted into it and in intimate surface contact with the inside of the parison. The parison is therefore in full surface contact with the first mold and preferably also with the second core for regulation of the temperature of the parison. The temperature of the first mold, the second core, or both can be controlled to optimize the condition of the parison for its orientation.

Alternatively, the parison can be separated from the first core into the first mold without substantially deforming, in which case the shape of the first mold is substantially the same as the shape of the parison, with a suitable surface between the two. Ensure contact. Sometimes the parison can be placed in a heated cavity that does not correspond to the shape of the parison, and such heated cavity takes the place of the first mold. This heated cavity is equivalent to the first type in the sense of the present invention, and it will be encompassed by the term "first type" throughout this specification.

In view of the plurality of cores and molds used in the present invention and the high degree of temperature control that can be achieved over the parison, the present invention provides a method for spinning the temperature-conditioned parison in a second mold at a predetermined rate by the second core. A multiaxially oriented product is obtained by stretching in the direction and expanding the parison to form a finished product. Additionally, the motion parameters of each component of the device of the present invention provide for highly efficient and smooth operation.

When seeking to produce multilayer parisons and multilayer end products, our U.S. Pat. No. 3,349,155;
According to US 3,717,544 and US 3,719,735, the first core can have one layer of one type of plastic, and the next layer can then be pressure molded around it. Therefore, when referring simply to parisons in the following general description, it is to be understood that the method and apparatus of the present invention applies just as well to multilayer parisons as to single layer parisons.

Thus, a multi-axially oriented product can be obtained according to the apparatus of the invention, which includes means for stretching the temperature-controlled parison in the axial direction at a predetermined rate;
and can be easily obtained, for example, by inflating the parison by means of an axially reciprocatable part of the second core actuated by means capable of adjusting the speed of reciprocation.

It will be appreciated that the apparatus of the present invention makes uniform temperature control of the parison efficient and convenient, so that the resulting articles are characterized by highly improved properties and at the same time high production rates are obtained. Orientation affects significant properties of plastics, such as transparency,
It is known to improve impact resistance, strength, penetration resistance, etc. Examples of plastics that can be modified are polystyrene, polyvinyl chloride, polyolefins, such as polyethylene and polypropylene, polyesters, polycarbonates, polyamides, acrylics, fluorocarbon resins, acrylonitrile polymers, and methacrylonitrile polymers. The improved temperature control of the present invention allows improved properties and controlled multiaxial orientation to be obtained in a simple and rapid manner.

The main object of the invention is therefore to provide an apparatus for manufacturing hollow articles from moldable organic plastic materials, which allows precise temperature control and rapid operating cycles.

Another object of the present invention is to conveniently and rapidly provide improved multiaxially oriented products under conditions of closely controlling temperature and deformation rate.

Yet another object of the invention is to provide a device as described above which provides a product with reproducibly uniform properties due to orientation.

Other objects and advantages of the invention will become apparent from the following description with reference to the accompanying drawings.

Referring to the drawings in detail, Figures 1, 2 and 3 illustrate an apparatus according to one aspect of the invention. In this embodiment, the parison is formed by injection molding, but the invention is not limited thereto, and includes other known methods by which parisons can be manufactured, such as compression molding, casting, secondary operations, etc. It also includes extrusion methods that do not include or do not include. FIG. 1 shows a parison die 10 having an outer wall 11 which can be separated depending on the shape of the parison and which is adapted to form the outer surface of the parison.
and an end wall 12 having a shape to form an end wall of the parison. The parison die 10 is, for example, connected to a suitable heat transfer source (not shown).
Heating or cooling means 10a contained therein
The temperature can be adjusted by means of which such temperature adjustment means can be arranged in several zones to obtain different temperatures in different areas of the parison. The end wall 12 of the parison die has an injection opening 13 aligned with an injection nozzle 14 through which organic plastic material is injected into the parison die. The parison die 10 is shown as being segmented for convenience in releasing the parison that has been opened. However, it should be understood that the invention is not limited thereto and that any integral die suitably designed to release the parison can be envisaged here.

As indicated above, the plastics contemplated according to the invention are moldable plastic materials, preferably those whose properties are improved by stretching, examples of which are: polyolefins. , such as polyethylene, polypropylene and their copolymers, polyvinyl chloride, polystyrene and other styrenic resins, acrylonitrile polymers, methacrylonitrile polymers, polyvinylidene chloride, polycarbonates, polyesters, polyamides, fluorocarbon resins, etc.

The formation of a parison according to the embodiments shown in Figures 1, 2 and 3 is shown in Figure 1 and in Figures 2-3.
A first core 15 (preferably blow molded), depicted in dashed lines in the figure, and a parison die 10 are engaged by suitable mechanical means, such as power means shown schematically in FIG. It will be done later. In the embodiment shown in Figures 1, 2 and 3, the first core 15 is engaged into the parison die 10 in the direction of the arrow and is capable of axially reciprocating movement therein and out. Upon completion of injection through nozzle 14, a parison 16 having the shape substantially shown in FIG. 2 is formed.

The side walls 17 and ends 18 of the first core 15, the walls 11 and 12 of the parison die 10, and the neck mold 20 constitute the die cavity in which the parison is formed. The first core 15 is 1 or 2
In said zone, the temperature can be controlled, for example, by internal heat exchange means contained therein, said heat exchange means being connected to a suitable heat transfer or power source (not shown). ing. 1st
Core 15 is supported by platen 19. The assembly further includes a neck die 20 in which the neck of the parison is formed, and the neck die 20 engages the parison while the parison engages onto the blown or first core 15 after separation from the parison die. stay in the state,
The temperature of the neck mold 20 can be controlled independently. The neck mold can have threads 21 for forming threaded openings in the final molded product. The neck mold 20 can be split into two parts by suitable mechanical means, such as power means shown schematically in FIG. structure and thus can be separated as a unit from the parison.

During the separation of the parison die 10 and the first core 15, the parison 16 is cut by a neck die 20 or by other means, for example by an undercut.
If necessary, it will hold well on it. Once separated, the parison assumes the position depicted in FIG. 1 and indicated by dashed lines in FIG.

The first mold 22, which is a conditioning mold for adjusting the temperature of the parison to a suitable temperature for the final processing step, and which can be a preforming mold, and the first core 15 are shown in FIG. The illustrated first mold 22 and parison 16 are aligned to juxtapose each other, as initially indicated in dashed lines. As shown, the first mold 22 can be laterally reciprocated by suitable mechanical means, such as the power means shown schematically in FIG. Move in the direction of the arrow to align and then move out of alignment. The first mold 22 is often heated in a number of zones which may be arranged along its length, e.g. by heating or cooling means 22a connected to a suitable heat transfer source (not shown). , temperature controlled. Although not preferred, it is possible to align the first mold 22 and the parison 16 by a lateral or circular reciprocating movement of the first core 15.

Referring to FIG. 3, the first mold 22 and the parison 1
6 are aligned, the first core 15 and the parison 16 are then aligned, e.g.
The axial movement of the first core 15 places it in the first mold. Other means of engaging the parison and mold can be used and are well known, such as those disclosed in US Pat. Nos. 2,853,736 and 2,974,362. The parison is then released from the first core and placed into the first mold 22. This is done, for example, by axial stripping and can be facilitated, if necessary, by partially expanding the parison. Partial expansion is achieved by making the mold cavity of the first mold 22 slightly larger than the parison and by applying fluid pressure inside the parison through channels 27, thereby expanding the parison to form the first mold. This is carried out by matching the cavity of No. 22. The flow path 27 is formed within the first core 15, and a valve may be provided at the end thereof. Next, the first core 15
Separation of the parison from the first core can be facilitated by pneumatically separating the parison from the first core, whereupon the parison remains in the first mold 22. It should be noted that such dilation is not always necessary, but is often helpful. If desired, an outlet channel (not shown) can be formed on the first mold 22 to remove air from the mold cavity as the parison enters to facilitate establishing contact between the parison and the mold walls.

The temperature of the first mold 22 is regulated by heating or cooling means 22a connected to a suitable heat transfer source (not shown) or by means of heaters to maintain the temperature of the parison for subsequent operations in the manner described below. Optimal. Suitable heating or cooling means may be used in any of the heating or cooling coils described herein, such as passages containing a heat transfer fluid maintained at a suitable temperature, electrical resistance heaters, or radiant heat sources.

FIG. 3 shows the molded parison 16, for example.
The parison 29 is illustrated as partially inflated by application of fluid pressure to match the shape of the mold cavity in the first mold 22. The shape of the partially inflated parison 29 is such that a second core, such as a blow core 30 having a stretching function, can be inserted and contacted substantially the entire surface therein, as shown in FIG. , the contact between the second core and the parison can provide overall heat exchange. In such cases, the shape should not exhibit undercuts or reverse curves on its inner surface, such as by an outward taper on its inner surface. However, the shape of the parison does not always allow this, for example in some cases of long narrow necked parisons, and in those cases it may be necessary to pre-contact heat the inside of the parison. be.

After the parison is completely transferred into the first mold 22, the mold and the first core 15 are separated. This separation is effected, for example, by moving the first core and the first neck mold axially in the direction of the arrow and at the same time applying normal air pressure by the first core to the inside of the parison; The parison 29 thus transferred is held within the first mold 22. The first core 15 and neck mold 20 are then returned to the starting position as shown in FIG. 1, and the first mold 22 containing the parison 29 which may have been partially expanded
is moved laterally to the position shown in FIGS. 1 and 2.

Parison 29 held within first mold 22
is thereby transferred into alignment with the second core 30. The second core 30 is supported by the platen 31 and can have temperature control means and can have an external shape that matches the internal shape of the parison 29. Whenever axial stretching of the parison is desired, the second core 30 may include a stretching and blowing assembly that reciprocates as indicated by the arrows in FIG. 1 to axially stretch the parison 29. It consists of a mandrel extension 32 that can be extended. Actuation means are shown consisting of a push rod 34, which engages the extension 32 and is connected to a piston 35 housed in a cylinder 36, which can be driven, for example, by a pump, not shown. can respond to the hydraulic pressure exerted. By adjusting the flow of fluid into the cylinder 36, the speed of the piston 35, and thus the speed of the moving parts of the second core 30, is adjusted to stretch the parison at a speed most appropriate to the temperature of the parison. can. Such actuation means is merely illustrative of one method of operation, and other actuation means known in the art may be used herein. If a highly oriented product is not desired, the axial stretching operation can be omitted.

For the last molding order, the parison is
Separate from 2. This places the parison in the neck region on the second core 30 and sometimes also on the neck mold 37 which operates in the same way as the neck mold 20.
This is done by holding. When the neck mold 37 is not present, retention of the parison to the second core 30 can be achieved by tightly fitting the second core 30 into the parison neck or by tightening the parison neck as shown in FIG. 1A. An inflatable sleeve 3 made of an elastomer or the like is disposed in the neck area of the second core 30, which is arranged to be gripped therein.
This can be achieved by providing 0a.
Such a sleeve may now be inflated, for example, by applying air pressure from the second core to the sleeve via fluid passageway 38.

The second core 30 is disposed in a spaced relationship with the first core 15 and the first mold 22 is disposed in a spaced relationship with the first core 15 .
and are placed in spaced relationship to allow both cores to engage their respective molds when the first core 15 is aligned with the first mold 22 as shown in FIG. This facilitates simultaneous temperature regulation and final shaping of separate parisons. Furthermore, with respect to the transfer of the parison 29 to the second core 30, the parison die 10 is spaced apart from the first mold 22, as shown in FIGS. It should be noted that the second core 30 can engage the first mold 22 to form another parison, and at the same time the third core 41 can release the fully expanded product 40. be.
The ability to perform the various tasks outlined herein simultaneously constitutes one of the significant advantages of the present invention. Simultaneous molding of several parts or final expansion and removal of the final product is conceivable. This is because the apparatus illustrated in the accompanying drawings can be further modified to provide additional intermediate molds and cores, such as the first mold 22 and the second core 30, for example.

A fluid passage 38 is provided, which terminates at the end face of the portion of the second core 30 that does not move during movement of the extension 32. Fluid passageway 38 is also connected to a source of pressurized fluid, not shown. Thus, once the passageway 38 is opened by the movement of the extension 32 and the corresponding movement of the movable part of the second core 30;
Fluid can enter the space inside parison 29 during the final expansion described below. When the transfer of the parison from the inside of the first mold 22 to the outside is facilitated by grasping the parison from the inside as shown in FIG. Pressurized with air,
Inflate the sleeve against the inner half of the parison neck.

It will be appreciated that in cases where the second core 30 can be matched to the inner contour of the parison 29, the second core 30 can be heated or cooled. Thus, the temperature of the parison 29 can be regulated by heat exchange between the inner and outer surfaces of the parison 29 and the corresponding mold and core surfaces.

The parison 29 is thereby subjected to subsequent processing, e.g. axial stretching and final expansion.
Can be prepared quickly and uniformly. This is a considerable advantage as it avoids the problem of cooling the parison during the multi-step process. When making the second core 30 to match the shape of the parison 29,
Since the inner surface of the parison 29 is in heat transfer relationship with the second core 30, heat transfer is further improved than if only the outer surface of the parison 29 were in heat transfer relationship with the corresponding mold element. Naturally, a conventional temperature regulator used to control the heating means of the second core 30 and the first mold 22 may be used to control it independently in several zones within the assembly, corresponding to the desired temperature profile. It can be done.

When rapid operating cycles are of interest, it is particularly advantageous to first rapidly change the heat content of the parison 16 by heat exchange with the first core 15 and the parison die 10 to obtain the desired heat content for the subsequent operation. However, this is almost always at the cost of an uneven temperature distribution within the parison.
This is followed by heat exchange with the first mold 22 to substantially equalize the temperature distribution across the wall thickness of the parison;
And whenever matching the inner wall of the parison with the second core 30, it is necessary to avoid a layered pattern of final product properties that corresponds to the known relationship between final product properties and deformation temperature. This procedure is detailed in Japanese Patent Publication No. 53-30731 filed by the applicant of the present application. That is, for example, forming the parison 16 by injection molding and rapidly cooling the parison by heat exchange with the first core 15 and the parison die 10 (this provides rapid cycling, but also produces the uneven temperature distribution). ), then substantially equalizing the temperature distribution across the cross-section of the parison, all in a controlled manner, giving the parison the desired temperature profile for orientation. Naturally, the parison remains in the first mold 22 until the necessary desired temperature distribution adjustment is obtained. Alternatively, according to the invention, the preformed parison is placed in a parison die 10 and the parison die 10 is heated by heat exchange with the parison die 10 and the first core 15.
0 (which also tends to produce an uneven temperature distribution), and furthermore the first
Further processing is performed in the first mold 22 by heat exchange with the mold 22 and the second core 30 to substantially equalize the temperature distribution of the parison. The method achieves a predetermined temperature profile of the parison,
It offers the considerable advantage of being able to obtain optimal conditions for orientation without excessively long residence times in the mold. While the first mold is completing conditioning the parison, the parison die is released for further use, resulting in a rapid processing cycle.

Referring to FIG. 2, the transfer of the parison 29 to the second or finishing mold 23 is effected by a second core 30 which engages the first mold 22 and the parison 29. On top of that, parison 2
9, the second core 30 is separated from the first mold 22, which can be separated to release the parison 29, by moving the second core 30 by suitable mechanical means, such as power means shown schematically in FIG. separated by. Once released, the second core 30 with the parison 29 thereon returns to the position illustrated in FIG. 1 and depicted in dashed lines in FIG.

According to the apparatus of the invention, the second mold 23 is in a laterally spaced relationship with the first mold 22;
And the second type is solid. A second type of fixed or stationary position represents a significant advantage of the device of the invention. Thereby, the parison can be placed very quickly and therefore with less influence on the temperature of the parison. Also, the second mold 23 can weigh several tons if it is a multi-layer mold (which is often the case). Moving such masses at high speeds requires laborious, expensive, and highly inefficient means of controlling the acceleration and deceleration of this motion. In contrast, the parison and core assembly weighs only a few pounds;
It can be moved quickly by simple means, for example an air cylinder with a buffered end.

As can be seen in Figures 1 and 2, a third core or product removal plug 41 for removing the final product is in integral, laterally spaced relationship with the second core 30. The third core is supported by the platen 31. Therefore, when the second core engages the parison 29 in the second mold 22, the ejection plug or third core 4
1 engages the finished product 40 in the second mold 23.
As shown by the arrows, the second core and the third core can reciprocate axially and laterally, so that the second core moves the parison 29 from the first mold 22 to the second mold 23 axially and laterally. Transfer by a combination of directional and axial movements. At the same time, the third core 41 extracts the final product from the second mold 23, which can be divided and separated to facilitate the ejection of the final product, and a protrusion located transversely to the second mold 23 for ejecting it. The final product is transferred to the station, while the second core 30 is transferred to the second mold 23.
engage with.

The second core 30 with the parison 29 is then placed in the second mold 23, with the temperature of the parison 29 being adjusted as described above. parison 2
9 is stretched generally axially relative to the bottom of the second mold 23 by advancing the movable part of the mandrel extension 32 by means of a push rod 34 at a predetermined speed. Thus, the present invention can adjust and stretch the parison in the longitudinal direction before the final blow molding, thereby creating an axial orientation, as well as continuing to create the orientation by blow molding. The temperature of the parison prepared for extrusion and blow molding can be suitably and conveniently controlled by the respective molds and cores. While stretching is occurring, the passageway 38 is held open to equalize the pressure inside the parison with atmospheric pressure to prevent collapsing of the parison due to the reduced pressure created inside the parison as the interior volume of the parison increases during stretching. prevent. After the axial stretching is complete, the parison is fully expanded to conform to the shape of the finished mold, ie, the second mold 23, to form the final product 40, which in the illustrated embodiment is an open-ended container. Of course,
A wide variety of commercially known shapes can be manufactured, which can be, for example, bottles, jars or cups. Complete expansion is accomplished by supplying pressurized fluid through passage 38 into the interior of the axially extending parison 29, or occasionally and at various rates, as the parison is stretched.

After completing the complete expansion, the second mold 23 containing the second core 30 and the final object 40 is inserted into the first core 1.
5 and the first mold 22 as described above. The second core moves axially, laterally and axially, which positions the second core in the first mold 22 and at the same time removes the ejection core or third core 4.
1 into the finished product 40 and remove it after the finished product has cooled sufficiently for removal purposes.

In the embodiment illustrated here, the second or finishing mold 23 has two longitudinal sections 42 and 43.
The parts can be coupled and separated in a reciprocating manner by means of actuating means (not shown), for example a hydraulic cylinder. Thus, part 42
and 43 can leave in sufficient quantity so that the product can be removed by the third core 41;
The third core 41 can then be inserted into the product's neck with an interference fit. Prior to such mold opening and ejection, fluid pressure may be applied through the passageway 46 to effect the blow molding, if desired, in the case of continuous contact between the product 40 and the second mold 23 for extended cooling purposes. Can be continuous. Alternatively, the passageway 46 may continue to be used to provide cooling air to the inside of the finished product or to vacuum the inside of the finished product to help retain it.

Thus, the present invention improves the injection blow molding process and
It will then be seen that the steps of parison manufacturing, stretch orientation and circumferential orientation are carried out in a single continuous and completely controlled sequence. injecting or preparing a parison at a first station;
It is moved in the axial direction from the first station by the first core. The parison is then transferred by means of the first core into a first or tempering mold, which for that purpose is moved laterally into alignment with the first core. The first mold is then moved laterally along with its internal parison to a second station where the second mold is
The core is inserted into the parison and the second core is removed axially from the first mold along with the parison above it. The second core is then moved along with the parison above it to align it with the second mold;
It is then inserted therein for final processing into the finished product, and the finished product is ejected by means of the third or ejecting core.

The apparatus and method of the present invention are simple, convenient and advanced in nature. The parison is passed from the injection mold to the first core; from the first core to the conditioning mold or first mold; from the first mold to the second core which may be a stretch blow core; from the second core to the finishing mold or movement into the second mold and exit; or preferably movement from the finishing mold into the third projecting core and exit. The movement of each component is very simple, convenient, quick, and large,
The bulky finishing mold or second mold is stationary.

It has been found that the adjustment of parison temperature provided by the present invention results in an oriented product with consistently superior properties. The parison is injected into a relatively cold mold and remains in the cold mold for a very short time, but sufficient to remove from the parison an amount of heat corresponding to conditions best suited for orientation. do. The parison is then transferred to a conditioning mold or mold 1 which imparts an optimal orientational temperature profile to a given plastic article, and the parison naturally arrives from an injection mold with a poor cross-sectional temperature profile. Remain in the first mold for a sufficient time to equalize temperature across the wall thickness. After tempering, the parison with the correct temperature profile and excellent cross-sectional distribution is now placed in a cold finishing mold, in which it is stretched at a controlled speed and blow-molded. The steps of injection in the injection mold and residence therein; tempering and stretch-blow molding and cooling; and product removal occur simultaneously, allowing efficient use of the machine. Also,
The movement of the components allows smooth operation.

Naturally, many changes can be included. Nets can be made by injection molding or blow molding. The function of stretching can be omitted, in which case a highly efficient injection blow molding operation is provided. Instead of tempering, a second station can be used as the first blow molding station and a third station can be used as the second blow molding station to split the cooling hold into two.
This may be desirable for thick walled products. In fact, additional cooling stations can be added.

In one modification, the parison is initially
It can be formed in situ and stored before being formed into a final product. In addition to injection molding, a number of methods are known that can be used to form thermoplastics into parisons, such as tube extrusion with one open end welded, dip molding, precipitation, thermoforming, etc. The previously formed parison is then transferred to the first blow molding core and placed thereon. 1st
The blow molded core cooperates with heating means to raise the temperature of the parison to a temperature at which it can be deformed.

It is often necessary to perform secondary operations on hollow materials made in accordance with the present invention. Examples of these are the attachment of base caps to articles with dome-shaped bottoms, as is often the case with bottles that have to withstand considerable internal pressure, for example carbonated drink bottles. Such base caps are usually plastic dish-like articles with a flat bottom, the inside of the dish being glued to the convex bottom of the bottle to allow the bottle to stand upright on a flat surface.
Such base caps are usually attached with a special device to which pre-made bottles are randomly fed.

According to the refinement exemplified by the variant of FIG. 4, such a separate device can be omitted and instead the base cap applicator can be coupled to the device of the invention itself. According to the embodiment of FIG. 4, a base cap applicator is provided for attaching the base cap to the bottom of the finished product. This applicator is laterally spaced relative to the second mold so that when the second core and parison are engaged with the second mold (FIG. 3), the applicator supporting the base cap is inserted into the ejection plug. engages the bottom of the finished product supported on the bottom of the finished product. As shown in FIG. 4, the base cap applicator 50 is mounted on a suitable platen 5 movable in the direction of the arrow by suitable power means.
1 is supported. The applicator includes a sleeve portion 52 and a bottom base cap carrier 53. In operation, carrier 53 is loaded with base cap 54 by conventional means (not shown). The base cap may have adhesive 55 at predetermined spaced locations for attachment to the bottom of the finished product.
The base cap carried by applicator 50 then engages the bottom of finished product 40 and sleeve 52 surrounds the finished product to protect it from buckling. Air pressure can be supplied to the inside of the finished product from passages 46 in the third core 41. Pressure is then applied to the carrier 53 in the direction of the arrow to press the cap 54 firmly against the bottom of the bottle 40. If an adhesive 55 is used, when its required curing time has elapsed, the applicator is now applied to the finished product 4 with the base cap 54.
0 and remove the article from the plug or third core.

As is well known, in injection molding,
It is desirable to minimize the length of the molten plastic flow and to group the individual cavities together into a multi-cavity mold to minimize platen space, which allows the mold to flow under high injection molding forces. The precision of the molded part is increased because the risk of deflection of the support structure is reduced. As shown in the schematic diagrams of Figures 5, 5A and 5B using an apparatus according to Figures 1, 2 and 3, a plurality of first cores are supported at intervals with respect to each other by common support means. a plurality of first molds supported in spaced relation to each other by a common support means; a plurality of second cores supported in spaced relation to each other by a common support means; and a plurality of second molds supported in spaced relation to each other by means, in which a plurality of finished products are simultaneously produced. Naturally, the mold can be divided for convenient removal of the product or parison. As shown in FIG. 5, cavities 111 in several parison dies 110 are connected to a common support means, that is, a first core 11 supported by a support plate 119.
They are arranged in rows that cooperate with 5. The parison die 110 cooperates with an injection unit 114 from which molten plastic is injected through a channel 113 and distributed by a runner 113a. The spacing between cavities 111 corresponds to the dimensions of the parison. Therefore, the spacing of the second core 130 supported by a common support means, platen 131, separates the parison made in the cavity 111 from the first, second and third cores.
When transferring by the method shown in the figure, the cavity 111
must correspond to the interval of The parison is then transported through a processing cycle in some manner after FIGS. 1, 2 and 3 using a plurality of first molds 122 and a plurality of second molds 123.

Hollow products made from parisons are often so much larger than the parison that they cannot be accommodated with the same center spacing as the parison. For example, a parison for large bottles is 1.5 inches (3.8
cm), whereas bottles made from this parison can have a diameter of 4 inches (10.2 cm). According to the embodiment of Figures 5A and 5B, which represent schematic plan views of the second core in two different positions, means for moving the second cores away from and towards each other in a predetermined relationship are provided. provided. The apparatus according to FIGS. 5A and 5B accommodates the large center spacing of the finished product while maintaining the compressed configuration of the parison type as shown in FIG. The second core 130' has two columns 1
31' and 131'' are provided to mate with two corresponding rows of parisons (not shown). Means for spreading the two rows of second cores in the direction of the arrows, e.g. A spreader rod 150 is provided which is connected to the power means so that once the parison supported by the second core 130' has completed its tempering cycle in the first mold (the position shown in Figure 5A). , and when the parison is separated from them, the spreader rod 150 moves to spread the second core 130' to the centerline of the finishing cavity of the second mold (in the position shown in FIG. 5B). After blow molding, the second core is removed from the hollow article and moved again to the centerline of the first mold in time to begin the next cycle.

FIG. 6 further illustrates an improvement intended for the handling of parisons made from plastics that require an extended tempering cycle prior to biaxial orientation by stretching and blow molding. Of these plastics, polypropylene is most prominent, requiring heat cycles on the order of minutes, compared to seconds for other materials. The problem with equipment for this type of material is that it requires at the same time not extending the actual operating cycle of the equipment and constructing a very bulky and inefficient heating device.
This means introducing an extended refining cycle. FIG. 6 is a schematic representation of an apparatus that achieves the above object by including a plurality of first molds movable to spaced positions from the core for extended adjustment of the temperature of the parison; . In the embodiment shown in FIG. 6, a multi-stage arrangement is provided in the refining station showing a plurality of first molds 222. In operation according to FIGS. 1, 2 and 3, when the first mold 222 with the parison reaches the tempering station, the first mold 222 is moved laterally to the adjacent position A by conventional power means. In the next cycle, the first mold 222 may be further moved laterally to an adjacent position A', etc., so that the number of such lateral positions will depend on the actual desired tempering cycle. As shown in FIG.
B″, from here it moves further to position B′,
From there it goes to position B, from which it is raised to the higher original stage, ie, the position where the first mold 222 first entered the tempering cycle. Position A,
A' etc. and B, B' etc. can of course be placed on one side or both sides of the refining station. As can be easily seen, this simple lateral movement and elevator arrangement allows the parison to undergo a certain prolonged and desired tempering, without disturbing the entire operating cycle of the machine. thus,
Machine output will remain the same regardless of temper residence time as long as a sufficient number of first molds are used. Naturally, all molds in the circulation can be connected to an energy source, for example in the case of electric heating, the power can be reached to each mold via a sliding connector cooperating with a suitable common busbar.

According to the embodiment of FIG. 6, the parison arriving at the first mold, i.e. the tempering mold, is not removed from it by the second core, but before reaching it, the first mold is transferred to the side. to provide an extended refining cycle.
Meanwhile, the parison is kept under controlled temperature conditions. The length of time for this residence will depend on the number of molds being circulated. The tempered parison is removed at position B.

Instead of the above-described preferred device for using a plurality of first molds as described above, it is considered to move a plurality of first molds along different paths, for example in a cycle which can be vertical or horizontal. be able to. However, care must be taken to hold the parisons in a vertical position to avoid their distortion and to keep the mold in contact with the temperature control device.

In summary, in accordance with the embodiment of FIG. 6, an apparatus is provided for forming articles from moldable plastic materials that require extended heat cycles to obtain conditions suitable for orientation, the apparatus comprising forming a parison prior to orientation. a plurality of first molds for holding, whereby the first molds sequentially receive and release parisons;
The overall cycle of the device is thereby substantially unaffected by the number of first types. Preferably,
The apparatus is of the type shown in FIGS.

As previously discussed with respect to FIG. 4, secondary operations can be performed at the ejector station as required. One example of a secondary operation is the base cap 5
4 to the finished product by means of a base cap applicator 50. Of course, other secondary operations can easily be carried out at the ejector station as shown in my above-cited U.S. Pat. However, by other suitable means of limiting the walls of the article, it is possible to fill the article while limiting the finished article. This method facilitates hot filling of the finished article and, if necessary, restricting the filled article until it is sufficiently cooled to be handled.

The invention may take other forms or be carried out in other ways without departing from its spirit or essential characteristics. Accordingly, the embodiments of the invention are to be considered in all respects as illustrative and not to be limiting; the scope of the invention is indicated in the claims, and the scope of the foregoing meaning and equivalents is to be understood as follows: All changes within are intended to be contained within them.

[Brief explanation of the drawing]

FIG. 1 is a partially sectional side view of the device of the invention. FIG. 1A shows a modification of the core in the device of FIG. 2 and 3 are drawings similar to FIG. 1, with additional dashed lines, showing the sequence of operations according to an embodiment of the invention. Figure 4 shows
4 is a partial view similar to FIGS. 1-3 showing a modification of the device of the invention; FIG. FIG. 5 is a schematic side view similar to FIG. 1 showing a plurality of cores and molds. Figures 5A and 5B show a second example of a modification of the embodiment of Figure 5;
FIG. 3 is a schematic plan view of the core. FIG. 6 is a schematic diagram showing a plurality of first cores in a modified embodiment of the device of the invention. The reference numbers and alphanumeric characters in these drawings have the following meanings: 10... Parison die, 10a... Heating or cooling element, 13... Injection opening, 14... Injection nozzle, 15... First core, 16... Parison, 1
9... platen, 20... net mold, 22... first mold, 22a... heating or cooling element, 23...
2nd type, 27... channel, passage, 29... partially expanded parison, 30... second core, stretch blow core, 34... push rod, 35... piston, 36... cylinder, 37 ...netsuku type,
40...Completely expanded product, 41...Third core, product removal plug, 50...Base cap applicator, 51...Platen, 54...
Base cap, 110...Parison die, 11
1...Cavity, 114...Unit, 115
...First core, 122...First type, 123...
Second type, 130...Second core, 130'...Second core, 131...Common support means, platen, 150...Spreader bar, 222...First
Type, A, A', B, B', B''...position.

Claims (1)

[Scope of Claims] 1. An apparatus for forming an article from a moldable organic plastic material; a first core and a first mold spaced apart from each other and engageable with each other; engaged with the first core; means for providing a parison on the first core at a location spaced apart from a location where the first core and the first mold are mutually engageable; means for positioning the parison in the first mold in cooperation with the first core while retaining the parison in the first mold to adjust the temperature of the parison; a second core and a second mold spaced apart from the first core and the first mold, respectively, wherein the second core and the second mold are separated from each other;
a core is reciprocatable into engagement with and out of engagement with the second mold, and the second mold is stationary; means for engaging the parison in a position spaced apart from the first mold, thereby transferring the parison to the second core; moving the second core and the parison retained therein to a position spaced apart from the first mold; and means for cooperating with the second core to expand the parison on the second core within the second mold to form a finished product. A device characterized by: 2. The first core is capable of reciprocating in the axial direction, the first mold is capable of reciprocating in the transverse direction, and the second core is capable of reciprocating in the axial and transverse directions. An apparatus according to claim 1. 3. includes a product removal plug for removing finished product in integral spaced relation to said second core, such that said second core is connected to said first core.
2. The apparatus of claim 1, wherein the ejection plug engages the finished product in the second mold when engaging the parison in the mold. 4. The device of claim 1, including an inflatable sleeve internally gripping the parison neck in the neck region of at least one of the first and second cores. 5 includes a base cap applicator for attaching the base cap to the bottom of the finished product;
The applicator is in a laterally spaced relationship with the second mold such that when the second core and parison engage the second mold, the applicator engages the bottom of the finished product. An apparatus according to claim 1. 6. The apparatus of claim 5, wherein the applicator includes a sleeve portion that surrounds the finished product when the applicator engages the finished product. 7 a plurality of first cores supported by a common support means and spaced apart from each other; a plurality of first molds supported by a common support means and spaced apart from each other; , a plurality of second cores supported by a common support means in spaced relation to one another, and a plurality of second molds in spaced relation to one another by a common support means. claim 1, comprising: producing a plurality of said finished products at the same time;
Apparatus described in section. 8. The centerline of the first mold has a different center spacing than the second mold, and the device separates the first mold, the second core, and the second mold from their respective centerlines in a predetermined relationship. Relative movement away and toward the centerline aligns the core with the first mold for engagement with the first mold and for engagement with the second mold. 8. Apparatus according to claim 7, including means for aligning said second mold with said second mold. 9. The apparatus of claim 1 including means for axially stretching said parison in said second mold to form a polyaxially oriented final product. 10. The apparatus of claim 1, including a plurality of first molds movable to spaced positions from said first and second cores to extend and adjust the temperature of said parison. 11. At least one of the first core and the second core includes an inflatable sleeve arranged to internally grip the neck of the parison in its neck region and hold the parison over the core. The device according to item 1. 12. Claim 1 further comprising: an ejection station in laterally spaced relation to said second mold for ejecting a finished product; and means for performing a secondary operation on said finished product. equipment. 13 including a plurality of first molds for holding the parison prior to orientation to form an article of moldable organic plastic material that requires an extended tempering cycle to obtain conditions suitable for orientation; Claims characterized in that the first molds thus receive and release the parisons sequentially and the overall cycle of the device is not substantially influenced by the number of the first molds. The device according to paragraph 1. 14 comprising a first core, means for preparing a parison on the first core, and means for cooperating with the first core to place the parison into one of the first molds, wherein 14. The apparatus of claim 13, wherein said first mold is movable to a position spaced from said core to extend and adjust the temperature of said parison. 15. The device of claim 14, comprising a plurality of first cores and a plurality of first molds engageable therewith. 16. The apparatus of claim 14, wherein the first mold is movable along a rotating path. 17 a second core in spaced relation to the first core and the first mold and a second mold engageable therewith;
means for transferring to a core and a second mold;
and means for expanding the parison on the core in the second mold.