Device and method for forming plastic preforms into plastic containers with damping means on the mold carriers and mold halves

Abstract

Device (1) for forming plastic preforms into plastic containers, which device has at least a first mold carrier (2) and a second mold carrier (3) for receiving blow-molded parts (4, 5), wherein the blow-molded parts (4, 5) are suitable and intended to form a cavity (8) within which the plastic preforms can be formed into the plastic containers, wherein at least one stop element (9) is arranged on a front side (V) and / or on a rear side (R) of the mold carriers (2, 3) on each mold carrier (2, 3), which stop element extends in the longitudinal direction (L) of the mold carriers (2, 3), and wherein, in a closed state of the mold carriers (2, 3), at least one stop element (9) of the first mold carrier (2) and at least one stop element (9) of the second mold carrier (3) lie opposite one another, characterized in thatthat at least one damping means (10) is arranged on at least one of two opposing stop elements (9), which damping means preferably extends in the longitudinal direction (L) of the mold carriers (2, 3).

Description

The present invention relates to an apparatus and a method for forming plastic preforms into plastic containers. Such apparatuses and methods have been known for a long time from the prior art. The plastic preforms are usually first heated and subsequently formed into plastic containers, such as plastic bottles, in particular, by exposure to a flowable and in particular a gaseous medium, which is advantageously compressed air, within a blow molding device. The blow moulding devices have blow moulds which usually have two side parts and a base part and which form a cavity which gives the shape of the plastics material containers to be produced. The cavity is accordingly in particular a negative mold of the plastic containers to be produced.Furthermore, such blow molding devices have at least two mold carriers and / or at least two mold carrier shells, within which the blow molds are arranged. The blow molds are usually arranged detachably on the mold carriers, wherein the mold carriers are designed in such a way that the mold carriers can be opened and closed by a relative movement of at least one mold carrier with respect to the other mold carrier, in order to arrange the plastic preforms to be formed inside the blow molds and remove the finished plastic containers again from the blow molds. Such blow moulding devices are known, inter alia, from EP 2 475 511 B1.In the devices known from the prior art for forming plastic preforms into plastic containers, the plastic preform or preform to be formed is accordingly brought between two opened mold carriers or mold halves and after closing the mold halves the preform is blown to the desired container. In order to achieve a damped closing of these mold halves, the mold carriers in the prior art are usually damped by means of a shock absorber.This procedure, however, is associated with some disadvantages. On the one hand, the closing of the mold carriers results in considerable wear on the shock absorbers, which in turn leads to a high maintenance outlay and to high costs for, for example, new components. On the other hand, the closing of the mold halves is very noise-intensive and, in particular, the meeting of stop plates or stop elements arranged on the mold carriers sounds "unpleasant". In this case, it also occurs that these stop plates strike one another without damping, as a result of which wear likewise occurs.The object of the present invention is therefore to provide a device and a method with which / with which wear and noise reduction is made possible when closing mold carriers. This object is achieved by means of a device according to the invention having the features of claim 1 and of dependent claims 2 to 8 and by means of a method according to the invention having the features of claim 9 and of dependent claim 10.An apparatus according to the invention for forming plastics material pre-forms into plastics material containers has at least one first mould carrier and one second mould carrier for receiving blow-moulded parts, wherein the blow-moulded parts are suitable and intended to form a cavity within which the plastics material pre-forms can be formed into the plastics material containers, wherein at least one stop element is arranged on each mould carrier on a front side and / or on a rear side of the mould carriers, said stop element extending in the longitudinal direction of the mould carriers and wherein, in a closed state of the mould carriers, at least one stop element of the first mould carrier and at least one stop element of the second mould carrier are opposite one another.According to the invention, at least one damping means is arranged on at least one of two mutually opposite stop elements, which damping means preferably extends in the longitudinal direction of the mold carriers. This means that at least one damping means is provided on the front side and the rear side of the mold carriers, so that when the mold carriers are closed the stop elements do not meet directly, but at least one damping means is arranged between them. Advantageously, the damping means is accordingly arranged in a sandwich-like manner between two stop elements in a closed state of the mold carriers 2, 3.The front side is understood to mean that side from which the plastic preforms are introduced into the mold carriers or the apparatus for forming plastic preforms and on which preferably a locking device for locking the mold carriers is also arranged. The rear side is understood here to mean that side which is remote from the front side and on which a shaft mounting is preferably arranged, on which the mold carriers are preferably pivotably mounted for opening and closing the mold carriers.The apparatus for forming plastic preforms into plastic containers is preferably a blow molding device or a blow molding station. In an advantageous embodiment, a plurality of such blow moulding devices are arranged on a common movable carrier. This carrier is in particular a rotatable carrier. The front side of the mold carriers is therefore preferably a side located radially outward, as viewed from the carrier, or a side facing away from the carrier, and the rear side of the mold carriers is preferably a side located radially inward, as viewed from the carrier, or a side facing the carrier.By means of this damping means, which is preferably arranged between two mutually opposite stop elements, it is accordingly achieved in particular that the volume is reduced when the stop elements strike one another, as a result of which the wear on the stop elements is also significantly reduced. Furthermore, the omission of the shock absorbers also achieves a considerable cost saving, since this eliminates the maintenance outlay and the costs for new shock absorbers, which are necessary in the prior art as a result of the arising wear on the shock absorbers. Lubrications which may be required can also be omitted by the damping means, which is advantageous in particular in applications within a clean room.The device according to the invention accordingly describes a damped striking of the stop elements and thus also of the mold carriers. Preferably, therefore, at least one stop element is mounted on one of the mold carriers and at least one stop element on the second mold carrier in such a way that they meet upon closing. These stop elements can preferably be attached at different points of impingement of the two mold carriers, wherein a damping means is located on at least one of two opposite stop elements. This damping means is preferably fastened to the stop element in such a way that it no longer strikes directly against one another with the opposite stop element, but the closing process takes place in a damped manner by the damping means.In a preferred embodiment, a plurality of blow moulding devices are arranged within a blow moulding machine and particularly preferably within a stretch blow moulding machine. This means that the plastic preforms are expanded to the plastic containers by application of compressed air. For this purpose, the apparatus preferably has a blowing nozzle which can be placed against an opening of the plastics material pre-forms in order to thus subject the plastics material pre-forms to blowing air or to expand them by means of blowing air. In addition, a valve arrangement is preferably also provided which controls the supply of the blowing air to the plastics material pre-forms.In a further advantageous embodiment, the blow moulding devices or the blow moulding stations each have stretching rods which stretch the plastics material pre-forms in their longitudinal direction. Particularly preferably, the blow molding machine or the carrier and the blow molding arrangements are arranged within a clean room which delimits the blow molding machine with respect to an immortal environment. Drive devices for closing, locking and / or opening the blow moulds are preferably arranged outside the clean room.The blow moulding devices are preferably transported within the clean room, wherein the clean room is preferably bounded by a plurality of walls. Preferably, the clean room is bounded by at least one stationary wall and a wall moving opposite the stationary wall. In this case, for example, the carrier on which the blow moulds are arranged can already have or form one of these walls and in particular the moving wall. The clean room in this case delimits the blow moulds in particular from an immortal environment.In a preferred embodiment, at least two damping means are arranged on the front side and / or the rear side of the mold carriers, which damping means are preferably spaced apart from one another in the longitudinal direction of the mold carriers. Preferably, both the stop elements and the damping means accordingly extend in the longitudinal direction of the mold carriers.In a further preferred embodiment, at least two stop elements are arranged on each mold carrier on the front side and the rear side of the mold carriers. Preferably, these stop elements in turn extend in the longitudinal direction of the mold carriers and also preferably extend in the longitudinal direction of the mold carriers at a distance from one another.Preferably, in a further embodiment, two damping means are arranged between two mutually opposite stop elements. This means that a damping means is arranged in each case both on the stop element which is arranged on the first mold carrier and on the stop element which is arranged on the second mold carrier. In a closed state of the mold carriers, these damping means are accordingly preferably situated opposite one another and are pressed against one another. With such an embodiment, the damping effect is increased again, so that an even smoother closing of the mold carriers is made possible. It is accordingly conceivable that depending on the material and configuration of the mold carriers or depending on the requirement, a plurality of damping means can also be provided between two mutually opposite stop elements, wherein these plurality of damping means are advantageously likewise arranged in a sandwich-like manner between two stop elements.In a particularly preferred embodiment, the damping agent is made of a material selected from a group of elastomers including butyl rubber (IIR), chloroprene rubber (CR), ethylene vinyl acetate (EVA), fluororubber (FKM), isoprene rubber (IR), natural rubber (NR), nitrile rubber (NBR), polyvinyl butyral (PVB), silicone rubber (SIR), and the like. Advantageously, the elastomer is made of a rubber material. The design of the damping means from an elastomer has the particular advantage that the damping effect can thereby be significantly increased, wherein this damping effect can be even further increased, in particular by two elastomers lying opposite one another.The damping means is preferably a plate-like or strip-like damping means or a circumferential damping means. The circumferential damping means can preferably be an annular damping means such as an O-ring, for example. Advantageously, the damping means can also be disk-like. The damping means can preferably also serve as a sealing element or sealing device for the mold carriers.In a further preferred embodiment, at least one of the blow molded parts has at least one bulge and / or groove on the front side and / or the rear side for receiving at least one damping means. In a preferred embodiment, it is accordingly also conceivable for both the blow molded parts and the mold carriers to have such damping means. Accordingly, at least one blow mould part and / or at least one mould carrier preferably has at least one damping means for damped closure of the blow mould and / or of the mould carriers.The applicant accordingly also claims protection for a device for forming plastic preforms into plastic containers, in which the damping means is arranged on at least one blow-molded part.The damping means of the blow-molded parts is preferably a circumferential damping means, which is preferably placed in the bulge and / or groove. Particularly preferably, this circumferential damping agent is an O-ring made of fluororubber agent (FKM) or the like. It is particularly preferably an O-ring with a cord thickness of between 3 mm and 8 mm, preferably between 4 mm and 7 mm and particularly preferably of 5 mm. The diameter of the O-ring can preferably vary depending on the space ratio and installation position.The present invention is furthermore also directed to a method for forming plastic preforms into plastic containers with at least one first mold carrier and one second mold carrier for receiving blow molded parts, wherein the blow molded parts form a cavity within which the plastic preforms are formed into the plastic containers, wherein the mold carriers are opened and closed by a relative movement of at least one mold carrier with respect to the other mold carrier and, in a closed state of the mold carriers, at least one stop element of the first mold carrier and at least one stop element of the second mold carrier, which are each arranged on a front side and / or on a rear side of the mold carriers, are opposite each other.According to the invention, at least one damping means is arranged on at least one of two mutually opposite stop elements, by means of which damping means the closing movement of the mold carriers is damped. Advantageously, a damping means is accordingly also arranged on the method side in a sandwich-like manner between two stop elements.In a preferred method, two damping means are arranged on the front side and / or the rear side of the mold carriers, respectively, which damping means are preferably spaced apart from one another in a longitudinal direction of the mold carriers, wherein the closing movement of the mold carriers is preferably damped again by means of these damping means.Accordingly, it is also proposed on the process side to arrange at least one damping means on the stop element of the first mold carrier and / or on the stop element of the second mold carrier, so that a damped impact of the stop elements and thus also of the mold carriers is achieved.Further advantages and embodiments are evident from the attached drawings:Shown therein are: FIG. 1 ashows a schematic representation of a first embodiment of the device according to the invention; FIG. 1 bshows a further schematic illustration of a first embodiment of the device according to the invention; FIG. 2a shows a first embodiment of a damping device; FIG. 2 b shows a further illustration of a first embodiment of a damping device; FIG. 2 cshows a further illustration of a first embodiment of a damping device; FIG. 3 shows a second embodiment of a damping device; FIG. 4 shows a side view of a second embodiment of the device according to the invention; FIG. 5 shows a top view of a second embodiment of the device according to the invention; FIG. 6 ashows a schematic representation of a blow molded part with damping means; and FIG. 6 bshows a further schematic illustration of a blow molded part.FIGS. 1 aand 1 b show schematic representations of a first embodiment of the device 1 according to the invention for forming plastic preforms into plastic containers. The device 1 has a first mold carrier 2 and a second mold carrier 3, wherein in this embodiment two stop elements 9 are arranged on a front side V and on a rear side R of the mold carriers 2, 3, respectively, on each mold carrier 2, 3. In this case, a damping means 10 is arranged in each case between two mutually opposite stop elements 9, with the result that in this embodiment a total of eight stop elements 9 and four damping means 10 are provided. The stop elements 9 and the damping means 10 extend in a longitudinal direction L of the mold carriers 2, 3. Preferably, the respective arrangements, consisting of two stop elements and a damping means 10, are spaced apart from one another in the longitudinal direction L of the mold carriers 2, 3.In contrast to the embodiments shown in FIGS. 1 aand 1 b, it would also be conceivable, however, that only one stop element 9 is arranged on the front side and the rear side of each mold carrier 2, 3, which preferably extends over the entire length of the mold carrier 2, 3.FIGS. 2a-2c show a first embodiment of a damping device 8, in this embodiment a damping means 10 is arranged between two mutually opposite stop elements 9. The stop elements 9 and the damping means 10 are shown spaced apart from one another in the illustration of FIG. 2 a. In an installed state of the damping device 8, however, the damping means 10 is fastened to one of the stop elements 9 and preferably fastened detachably to one of the stop elements 9. The arrangement of the stop elements 9 and of the damping means 10 is illustrated in FIGS. 2 band 2 c.Preferably, at least one stop element 9 has an engagement element 11 which cooperates with the damping means 10 or engages therein when the mold carriers are closed. This engagement element thus preferably also allows a tight connection and particularly preferably an airtight connection of the mold carriers, since the damping means 10 and the stop element 9 are thereby pressed firmly against one another. In addition, it is also conceivable for this engagement element 11 to be a fastening element of the damping means 10, on which the damping means 10 is fastened. In the embodiment of FIGS. 2 a- 2 c, the stop element 9 and the damping means 10 are designed as plate-like or strip-like elements. As already mentioned above, however, it is also conceivable for the damping means to be a revolving damping means, such as an O-ring, for example, or a disk-like damping means.FIG. 3 shows a second embodiment of the damping device 8. In this embodiment, two damping means 10 are arranged between two mutually opposite stop elements 9. In this embodiment, it is conceivable that the above-mentioned engagement element 11 is arranged on both stop elements 9.FIG. 4 shows a side view of a second embodiment of the device 1 according to the invention for forming plastic preforms into plastic containers. In contrast to the plate-like or strip-like damping means shown in FIGS. 1 a- 3, the damping means 10 according to FIG. 4 is a round damping means 10, for example in the form of an O-ring. The reference numeral 9 again identifies the stop elements arranged on the mold carriers 2, 3. Preferably, two damping means 10 are arranged on a front side V, which is illustrated in FIG. 4, and also on a rear side of the mold carriers 2, 3, which damping means are in turn spaced apart from one another in the longitudinal direction L of the mold carriers 2, 3. The reference numeral 17 identifies spacers arranged between the mold carriers 2, 3, which serve to prevent the mold carriers 2, 3 from being wedged when the mold carriers 2, 3 are closed.FIG. 5 further shows a plan view of the second embodiment of the device 1 according to the invention. In this case, in this illustration, in particular the shaft mounting 16 arranged on the rear side R of the mold carriers 2, 3 can be seen, about which at least one mold carrier 2, 3 is pivotably mounted in order to enable opening and closing of the mold carriers 2, 3 or of the device 1. Furthermore, the locking device 14 for the mold carriers 2, 3 and their bearing arrangement 15 can be seen on the front side V. This locking device 14 is preferably a lock which has elements which can be pivoted with respect to a pivot axis and which engage in one another for locking the mould carriers 2, 3. However, a locking mechanism with displaceable elements would also be conceivable.FIGS. 6 aand 6 b show a first blow mould part 4 and a second blow mould part 5, wherein the first blow mould part 4 here has two bulges 12 or grooves 12, in which a damping means can be arranged in order to enable damped closure of the blow mould. Furthermore, FIGS. 6 aand 6 b also show a cavity 7, within which the plastic preforms are transformed into the plastic containers. Accordingly, this cavity 7 is in particular a negative mold of the plastic containers to be produced.The applicant reserves the right to claim all the features disclosed in the application documents as essential to the invention, provided they are novel, individually or in combination, compared with the prior art. It is also pointed out that features have also been described in the individual figures, which features may be advantageous per se. The skilled person directly recognizes that a specific feature described in a figure can also be advantageous without the adoption of further features from this figure. Furthermore, the skilled person recognizes that advantages can also result from a combination of a plurality of features shown in individual figures or in different figures.List of reference characters1 Device 2 First mold carrier 3 Second mold carrier 4 First blow mold part 5 Second blow mold part 7 Cavity 8 Damping device 9 Stop element 10 Damping means 11 Engagement element 12 Bulge, groove 14 Locking device 15 Mounting of the locking device 14 16 Shaft mounting 17 Spacer V Front side R Rear side L Longitudinal direction of the mold carriers 2, 3

Claims

Device (1) for forming plastic preforms into plastic containers, which has at least a first mold carrier (2) and a second mold carrier (3) for receiving blow molded parts (4, 5), wherein the blow molded parts (4, 5) are suitable and intended for forming a cavity (8) within which the plastic preforms can be formed into the plastic containers, wherein at least one stop element (9) is arranged on each mold carrier (2, 3) on a front side (V) and / or on a rear side (R) of the mold carriers (2, 3), which stop element extends in the longitudinal direction (L) of the mold carriers (2, 3) and wherein in a closed state of the mold carriers (2, 3) at least one stop element (9) of the first mold carrier (2) and at least one stop element (9) of the second mold carrier (3) are opposite each other, characterized in that, at least one damping means (10) is arranged on at least one of two mutually opposite stop elements (9), which damping means preferably extends in the longitudinal direction (L) of the mould carriers (2, 3).Device (1) according to claim 1, characterised in that at least two damping means (10) are arranged on the front side (V) and / or the rear side (R) of the mould carriers (2, 3), which damping means are preferably spaced apart from one another in the longitudinal direction (L) of the mould carriers (2, 3).Device (1) according to at least one of the preceding claims, characterized in that at least two stop elements (9) are arranged on each mould carrier (2, 3) on the front side (V) and on the rear side (R).Device (1) according to at least one of the preceding claims, characterized in that two damping means (10) are arranged between two mutually opposite stop elements (9).Device (1) according to at least one of the preceding claims, characterized in that the damping means (10) is made of a material selected from a group of elastomers comprising butyl rubber (IIR), chloroprene rubber (CR), ethylene vinyl acetate (EVA), fluororubber (FKM), isoprene rubber (IR), natural rubber (NR), nitrile rubber (NBR), polyvinyl butyral (PVB), silicone rubber (SIR) and the like.Device (1) according to at least one of the preceding claims, characterized in that the damping means (10) is a plate-like or strip-like damping means or a circumferential damping means.Device (1) according to at least one of the preceding claims, characterized in that at least one of the blow moulding parts (4, 5) has at least one bulge (12) and / or groove each on the front side (V) and / or the rear side (R) for receiving at least one damping means (10).Device (1) according to claim 7, characterised in that the damping means (10) of the blow mould parts (4, 5) is a circumferential damping means.Method for forming plastic preforms into plastic containers, having at least one first mould carrier (2) and one second mould carrier (3) for receiving blow mould parts (4, 5), wherein the blow mould parts (4, 5) form a cavity (8) within which the plastic preforms are formed into the plastic containers, wherein the mould carriers (2, 3) are opened and closed by a relative movement of at least one mould carrier (2, 3) with respect to the other mould carrier (2, 3) and, in a closed state of the mould carriers (2, 3), at least one stop element (9) of the first mould carrier (2) and at least one stop element (9) of the second mould carrier (3), which are arranged in each case on a front side (V) and / or on a rear side (R) of the mould carriers (2, 3), are opposite one another, characterized in that, at least one damping means (10) is arranged on at least one of two mutually opposite stop elements (9), by means of which damping means the closing movement of the mould carriers (2, 3) is damped.Method according to claim 9, characterised in that two damping means (10) are arranged on the front side (V) and / or the rear side (R) of the mould carriers (2, 3), which damping means are preferably spaced apart from one another in a longitudinal direction (L) of the mould carriers (2, 3), by means of which damping the closing movement of the mould carriers (2, 3).

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