WO2004096517A2

WO2004096517A2 - Cork tool and corresponding production method

Info

Publication number: WO2004096517A2
Application number: PCT/EP2004/050588
Authority: WO
Inventors: Werner Plass; Stefan Schweininger
Original assignee: Mht Mold & Hotrunner Technology Ag
Priority date: 2003-04-28
Filing date: 2004-04-22
Publication date: 2004-11-11
Also published as: WO2004096517A3; DE10319025A1

Abstract

The invention relates to a method for producing injection-moulded parts from synthetic foam (18). Said invention also relates to a device for producing injection moulded parts from said synthetic foam (18) comprising at least one foaming cavity (14) for receiving synthetic foam (18) and at least one feeding system (2, 3, 4) for feeding with synthetic foam (18). The foaming cavity (14) is embodied in such a way that it receives synthetic foam (18) as far as a complete foaming of the injection moulded part is obtained. The aim of the invention is to develop a method and a form tool for producing a great quantity of corks having an as smooth look as possible during a short cycle time. For this purpose, the inventive method consists in introducing synthetic foam (18) into a moulding cavity (6, 7) with the aid of the feeding system (2, 3, 4), in separating said feeding system (2, 3, 4) from the moulding cavity (6, 7) and in foaming said synthetic foam (18) in the foaming cavity (5, 14). For this purpose, with regard to the device, at least two foaming cavities (14) are associated to each feeding system (2, 3, 4).

Description

Cork tool and process for the production thereof

The present invention relates to a method for producing injection molded parts from plastic foam, in particular a plastic cork, and a corresponding molding tool

Traditionally, wine but also champagne bottles are closed with corks, which are made from the bark of the cork oak. These corks are elastic and also impermeable to air and water, adapt perfectly to the neck of the bottle to be closed, prevent the wine from leaking or Sparkling wines, but at the same time allow a minimal oxidation during the aging years of the wine, which makes the maturation of the wine possible.However, only a cork with excellent quality can ensure this development, since the cork oak, which is only grown in a limited area, very much Slowly growing, the cork can usually only be extracted from the bark after about 25 years. If low-quality cork is used, it can change the wine and give it a cork taste that makes the wine inedible

As the demand for cork has increased significantly in recent years, the regeneration times of the cork oaks have been shortened and strengthening and treatment materials have been used to support the shorter recovery phases. This development has not only made cork extremely expensive, but also dramatic Increase in the so-called "cork tasters" led

There is therefore a need for a high-quality and, above all, taste-neutral alternative to traditional cork closures, especially for low-quality products

For example, metal closures have been used for some time, especially in the serving area for larger containers. However, these are only accepted to a limited extent, since the screw cap leaves the uncomfortable feeling with the end user that a high-quality natural product with a "cheap" composite made of plastic and metal is closed

For this reason, artificial corks have already been proposed which are produced from a plastic with a foam additive. The foam agent can be both a chemical and a physical foam agent under a chemical blowing agent For example, understood compounds that are added to the material to be foamed and expand due to chemical reaction, for example with decomposition and thereby foam the surrounding material. Physical foaming agents are understood to mean agents that change due to an aggregate change, for example from liquid to gaseous, or due to the expansion of a compressed one Expand gas when relaxing and thus cause foaming

An exemplary device for producing a plastic cork from the prior art is shown in FIGS. 1 and 2

The tool 1 has a feed device 2, 3, 4 and a mold cavity 6, 7 with a cavity 5 then formed. Through the feed device 2, 3, 4, which is equipped with a nozzle 3, which can be closed with a locking needle 4, the plasticized and heated plastic, which contains the foaming agent, is introduced into the cavity 5 of the mold cavity 6, 7. The plastic introduced initially takes up only a fraction of the volume of the cavity 5. The mold cavity 6, 7 is cooled and the tool remains in the Figure 1 closed position until the plastic introduced into the cavity 5 completely fills the cavity 5, that is, fully molded. In a further step, which is shown in Figure 2, the tool 1 is separated at the tool parting plane 8, so that the fully molded Cork 9 can be ejected from the cavity 5 with the help of the movable core 7 of the mold cavity 6, 7, even if the actual injection etching process is completed in about a second, a time of about 45 seconds must be estimated for the entire cycle, since the swelling of the plastic cork accordingly takes a lot of time. If the cork 9 is ejected from the cavity 5 too early, it may be due to of the incomplete foaming process, the cork 9 expands further and takes on an undefined shape. Therefore, in the devices known in the prior art, the tool remains closed for almost the full cycle of 45 seconds. This has the consequence that those achievable with the known devices Number of pieces of manufacture are limited. In addition, the cork 9, which is produced with the aid of the device shown in FIGS. 1 and 2, generally has a structure, for example a ridge, on its side facing the feed device 2 3, 4, which: is produced by the nozzle 3 or the closing needle 4 and the cork 9 has an unsightly appearance s gives or must be removed in a further processing step

It is therefore the object of the present invention to provide a method and a molding tool by means of which corks can be produced in short cycle times and thus in large quantities with a flat appearance

With regard to the method, this problem is solved by a method with the following successive steps Receiving foaming plastic into a mold with the aid of a feed device,

Separating the feed device from the mold cavity and

Foaming the plastic foam in a cavity

The fact that the supply device is separated from the mold cavity and thus from the molded casting part ensures that the side of the molded casting part facing the supply device is free of structures that are attributable to the specific design of the supply device the cavity still persists, can already be used for the next spitting process. As a result, the number of corks that are produced with the method can be significantly increased

In a particularly preferred embodiment, the plastic foam is cooled in the cavity, whereby the cycle time can be reduced

In a particularly expedient embodiment, the foaming of the plastic foam takes place in a cavity contained in the mold cavity

As an alternative, however, it can be provided that the foaming of the plastic foam takes place in a cavity which is separate from the mold cavity. In other words, the plastic is first introduced into the cavity of the mold cavity, begins to foam there, but is then removed from the mold cavity into the cavity according to the invention rearranged in which the actual foaming process takes place The last variant has the advantage that the same mold cavity is already available for the next molding process

Advantageously, the cavity is closed at least temporarily during the foaming process. As a result, the outer shape of the injection molded part, for example the cork, is predefined. Alternatively, the amount of plastic inserted can be calculated accordingly and either the inner contour of the feed device or the mold cavity can be selected in this way that the molded casting takes on the desired final shape after full foaming. This aspect is discussed in detail below

Even if the present invention has been developed with a view to producing a plastic cork, it goes without saying that other injection molded parts made of plastic foam can of course also be produced using the method according to the invention

With regard to the device, the object mentioned at the outset is achieved by a device for producing plastic moldings from plastic foam with at least one cavity for receiving the plastic foam and at least one feed device for feeding the plastic foam into the cavity is loosened, the cavity being intended to hold the plastic foam until the injection molding is fully foamed, with at least two cavities being assigned to each supply device according to the invention.This measure allows the foaming process to take place in one cavity, while at the same time the feeding device already uses the second cavity is filled with plastic foam

In a further particularly preferred embodiment, a mold cavity with a cavity for receiving the plastic foam supplied by the feed device is provided, the mold cavity and the feed mechanism relative to one another between an opening position in which the cavity is accessible from the outside and a shooting position in which the cavity is closed by the feed device, are movable. Furthermore, a removal plate is provided, in which the foam cavities are arranged, wherein the removal plate for receiving the plastic foam contained in the cavity of the mold cavity can be moved in the opening position between the mold cavity and the feed device , and means for transferring the plastic foam from the cavity into a foam cavity are provided. In other words, the plastic foam is first introduced into the cavity of the mold cavity with the aid of the feed device and begins here with the foam process Kur z then and especially before the completion of the foaming process, the tool is opened, ie the feed device is removed from the cavity of the mold cavity, and a removal plate in which the foam cavity is arranged is placed on or in front of the mold cavity in such a way that the foam is already partially foamed Plastic molding can be transferred from the cavity in the mold cavity into the foam cavity. The foam molding of the molded casting then takes place completely

For some applications it can be advantageous if the cavity has a slightly smaller internal volume than the foam cavity in order to facilitate easy transfer of the molded casting from the cavity into the foam cavity

In a further particularly expedient embodiment, the cavity of the mold cavity has essentially the shape of a blind hole and has a convex bottom. The convex bottom of the cavity ensures that the already partially foamed mold is transferred from the cavity into the foam cavity , has a concave shape at one end. Numerous experiments have shown that plastic corks, unless they are kept in a shape defined by the outer contour during the entire foaming process, expand more along their longitudinal axis in the center than in the edge areas If the convex-shaped bottom of the cavity is a partially foamed molding with a concave surface, the observed uneven expansion leads to the fact that the concavity of the plastic cork is reduced. If the bottom of the cavity is designed with a corresponding convexity formed, it is possible that the Shaped article which has a concave outer contour after it has been ejected from the cavity into the foam cavity, and has an almost flat base after curing

In an alternative embodiment, a cover plate is provided for closing the foam cavity. In this case, the convex-shaped bottom of the cavity can be dispensed with, since the cover plate ensures that the fully foamed cork has a flat bottom

In an expedient embodiment, an ejection device is provided for ejecting the fully foamed injection molding from the foam cavity. The foam cavity is advantageously in the form of a blind hole

In a further alternative embodiment, a cavity plate with at least one through hole and a tool element is provided, the feed device and the tool element being movable relative to one another between an open position and a closed position and the cavity plate being movable between the feed device and the tool element in the open position and The feed device, tool element and cavitation plate are designed and arranged in such a way that the tool element and feed device in the closed position close the through hole in the cavitation plate from both sides and thereby form the foam cavity. At least one cooling plate, preferably two cooling plates, is advantageously also provided, which are designed and designed in this way are movable that they can close at least one side of the bore of the Kavitatenpieatte, preferably both sides of the bore, if the Kavitatenpieatte not between d he feed device and the tool element is arranged In other words, in this embodiment, a type of perforated plate is pushed between the feed device and the tool element, the foaming plastic is filled into the perforated plate closed in this way by the feed device, the tool element and feed device are separated again, the perforated plate is removed from the tool and by means of the cooling plates closed again so that the full foaming process can take place, while the feed device can be used simultaneously for the next injection molding process

It is understood that a plurality of cavitation plates can advantageously be provided. In a particularly preferred embodiment, it is provided that at least one cover plate can be moved between two cavitation plates in such a way that each of the two cavitation plates closes one side of a corresponding bore Cover plate two holes of adjacent cavitation plates are closed

In a further alternative embodiment, the device according to the invention is designed as a circumferential tool, at least two foam cavities being circumferentially arranged in such a way that they are filled sequentially with the aid of the supply device with plastic foam and after complete foaming can be freed from the molded casting. It is thus possible for the plastic foam to foam in one foam cavity, while at the same time the non-foam plastic foam is introduced into at least one other foam cavity with the aid of the feed device

Advantageously, a circulation device with at least two closing elements for closing the at least two foam cavities is also provided after the foam cavities have been filled with plastic foam

Further advantages, features and possible applications will become apparent from the following description of preferred embodiments and the associated figures

1 shows a cork tool of the prior art in the closed state,

2 shows the cork tool of FIG. 1 of the prior art in the open state, FIG. 3 shows a first embodiment of the device according to the invention,

FIG. 4 shows a second embodiment of the device according to the invention,

FIG. 5 shows a third embodiment of the device according to the invention,

FIG. 6 shows a fourth embodiment of the present invention,

7 shows a fifth embodiment of the present invention, FIGS. 8 and 9 a sixth embodiment of the present invention

Figures 1 and 2 show a cork tool of the prior art in an open and a closed state. The operation of this tool has already been described

FIG. 3 shows a first embodiment of the device according to the invention. Here too, the cork tool consists of a feed device 2, 3, 4, which consists of a bottom insert 2 with a nozzle 3 that can be closed by a locking needle 4, and a mold cavity 6, 7 with a movable core 7 in a cavity 5 is formed in the mold cavity 6, 7

In a first step, as is also the case in the prior art, the mold cavity 6, 7, which is movable in the embodiment shown, is moved to the non-movable auxiliary duct 2, 3, 4, so that the cavity 5 in the mold cavity 6, 7 is closed by the feed device 2, 3, 4. Plastic foam is then introduced into the cavity 5 via the feed device 2, 3, 4

The plastic foam now begins to foam in the cavity 5.In contrast to the known molding tool shown in FIGS. 1 and 2, however, there is no waiting until the cork 9 is completely foamed, but the tool is opened before the foaming process has ended and the removal plate 10 that have at least one foam cavity 14 which, here is a blind hole, is pushed between the opened tool. In a next step, the cork 9, which has already been partially foamed, is transferred from the bore 5 into the foam cavity 14 with the aid of the movable mold core 7. In a further step, the removal plate is now removed 10 moved out of the tool and the foam cavity 14 closed with a cover plate 11. The cork 9 now remains in the foam cavity 14 until the foam process is essentially completely completed. In order to accelerate the foam process, both in the removal plate 10 and in the Cover plate 11 cooling channels 12 are provided, through which a cooling medium can be passed. Furthermore, there is an ejection device 13 which, after the foaming process has ended, after the cover plate 11 has been removed from the foam cavity 14, can eject the finished cork 9 from the foam cavity 14

It is obvious that the measure according to the invention, on the one hand, allows the corks 9 to be produced almost completely free of burrs and, on the other hand, the cycle time can be shortened significantly, since the feed device 2, 3, 4 can already be used again for a new spotting process, during the Cork 9 still foams in the foam cavity 14

FIG. 4 shows a second embodiment of the device according to the invention

Here, the feed device 2, 3, 4 is not assigned a mold cavity as is known in the prior art, but rather only a movable tool element 16. A cavitation plate 17 can be placed between the feed device 2, 3, 4 and the movable tool element 16, which plate has at least one through hole In the closed state of the tool shown in FIG. 4 below, the tool element 16, on the one hand, and the feed device 2, 3, 4, on the other hand, closes the through-hole in the cavitation plate 17, which is filled by the cork 9 in FIG. 4 Plastic foam to be foamed into the through-hole, the tool is opened, as shown in the center of FIG. 4, and the cavity plate 17 is moved out of the tool. In a next step, two cooling plates 15, 15 'are connected to the cavity plate 17 in such a way that the two openings of the through-hole pass through the cooling plates 15, 15 'are closed with a In other words, the actual foam cavity 14 is formed by the through-hole of the cavitation plate 17 and the cooling plate 15, 15 ', in which the cork 9 remains until it is completely foamed. This embodiment has the advantage over the embodiment of FIG. 3 that the cork does not must be transferred from the cavity 5 of the mold cavity into the foam cavity, but is filled directly into the corresponding foam cavity by means of the feed device 2, 3, 4

FIG. 5 shows a third embodiment of the device according to the invention Here, too, the actual molding tool, as in the embodiment described in connection with FIG. 3, consists of the feed device 2, 3, 4 and the mold cavity 6, 7. After the plastic foam 9 has been filled into the cavity 5 of the mold cavity 6, 7, here too the tool is opened, a removal plate 17 with through holes is positioned between the opened mold halves and then the plastic foam is transferred from the cavity 5 into the through hole of the cavitation plate 17 with the help of the movable mandrel 7. In the next step, the cavitation plate 17 is removed from the tool and the through hole from closed on both sides with corresponding cover or cooling plates 15 and 15 "In the embodiment shown in FIG. 5, a plurality of removal plates 17, 17 ', 17" are provided, which can be arranged in such a way that in each case one cover or cooling plate 15 " , 15 '"in each case one side of two bores of adjacent cavitation plates 17, 17', 17 "closed In this embodiment, several foam cavities are formed, which are filled in succession with the aid of the feed device 2, 3, 4, so that the feed device 2, 3, 4 can be used for filling a whole series of cavities during a complete foaming process

It goes without saying that the embodiment shown in FIG. 5 with a plurality of removal plates can also be used together with the embodiment shown in FIG. 4, in which the mold does not have an actual mold cavity 6, 7, but only a movable tool element 16, so that the plastic foam can be introduced directly into the through bores of the cavity plate 17, 17 ', 17 ", without the plastic cork having to be transferred from the cavity 5 into the cavity

FIG. 6 shows a further embodiment of the present device. In this embodiment, the feed device 2, 3, 4 is designed to be movable such that it can be moved in the direction of the corresponding tool element 19, 20, ie in the vertical direction. The tool element 19, 20 6, however, the tool element 19, 20 here consists of a cover plate 19 and a perforated plate 20, whereby of course cover plate 19 and perforated plate 20 can also be made in one piece, so that a kind of blind perforated plate results in the first step 6, which is shown on the right in FIG. 6, the feed device 2, 3, 4 closes the blind hole 14 formed by the cover plate 19 and the perforated plate 20, which forms the foam cavity, and non-foamed plastic foam 18 is fed via the feed device 2, 3, 4 in the foam cavity 14 filled in the next step, that in Figure 6 in the second n shown from the right, the feed device 2, 3, 4 is removed from the tool element 19, 20 and the tool element 19, 20 is moved laterally under the feed device 2, 3, 4. It can clearly be seen that the foaming process of the molded plastic 18th has already begun and will continue throughout the cycle. In the next step, a cover plate 15 is placed on the tool element 19, 20 so that the opening 14 is covered by the cover plate 15 in this state, which is shown in FIG. 6 on the far left the foaming process is completed, a cooling agent for accelerating the foaming process possibly being supplied through the cooling channels 12

FIG. 7 shows a further embodiment of the device according to the invention, in which the tool shown in FIG. 6 is designed as a rotating device. Here, a whole series of tool elements 19, 20 are fastened to a type of band 21, which in FIG. 7 is shown counterclockwise A single feed device 2, 3, 4 can fill the individual cavities of the tool elements 19, 20 one after the other. After filling, the correspondingly filled tool element 19, 20 is moved on and the cavity is closed with a corresponding cover element 15 that a number of cover elements 15 are provided with the aid of a kind of conveyor belt 22. The foam cavities are closed with the help of the cover elements 15 until the foaming process is essentially completely completed. Then the cavity is opened again, ie the cover element 15 is removed and the cork 9 in the further course removed from the tool element 19, 20, which is then available for the new filling by means of the feed device 2, 3, 4

A further example of a rotating tool is shown in FIG. 8. A feed device 22 with a total of 48 nozzles is shown in FIG. 8 above. The feed device 22 is shown in FIG. 8 as a cross-striped box, so that the individual nozzles cannot be seen below The feeding device 22 is arranged with a cavitation plate 23 with 48 cavities, each of which is assigned to a nozzle. In a first step, which can be seen in FIG. 8 above, plastic foam is therefore introduced into the cavities of the cavitation plate 23 via the nozzles of the feeding device 22 In the next section, the cavitation plate 23 is rotated counterclockwise and closed with a cover device, not shown. In the further steps 23 'and 23 ", the plastic foam is completely foamed and cooled. In steps 23'" and 23 "" the cavitation plate is opened again and the Ejected completely foamed plastic cork, before the cavitation plate is available for refilling with the aid of the feed device 22. In the embodiment shown, a total of six cavitation plates 23, 23 ', 23 ", 23'", 23 "" are available, which are successively filled by a single feed device 22

Finally, FIG. 9 shows a further embodiment of the device according to the invention. This embodiment essentially corresponds to the embodiment shown in FIG. 3, but with the mandrel 7 being convex, so that the cork 9, which has already been partially formed, is transferred from the cavity 5 into the cavity Cavity 14 of the removal plate 10 has a convex base 24, which is also referred to as champagne base. This so-called champagne base 24 is designed in such a way that the removal plate 10 does not have to be closed with the aid of a cover plate after it has been moved out of the tool the concavely curved bottom 24 is shaped such that after the plastic has completely hardened Korkeπs 9 an essentially flat bottom 24 is created. In other words, it is not absolutely necessary to completely close the cavity 14 during the foaming process

This embodiment has the advantage that only one removal plate 10 can be used. This is illustrated in FIG. 10, which shows the removal plate 10 in a plan view. Two groups of cavities 25, 26, which are represented by different hatching, can be clearly seen in FIG In a first step, the unshaded cavities 25 are filled with plastic foam. Then the removal plate 10 is moved in the opened tool in such a way that the hatched cavities 26 can be filled in a next step, while at the same time the plastic corks 9 in the unshaded cavities 25 harden Plastic corks 9 in the non-hatched cavities 25 are then ejected so that the non-hatched cavities 25 are available for refilling with plastic foam, while the plastic corks accommodated in the hatched cavities 26 are still completely hardened

It goes without saying that the embodiment shown in FIG. 10 with a removal plate which has more cavities than supply devices could also be used with a cover plate. In such a case, the cover plate could consist of one (or more) strip-shaped cover which closes a whole group of cavities, while another group is filled with the foaming plastic

The number of cavities in the removal plate is expediently an integer multiple of the number of feed devices which form corresponding groups of cavities. In the embodiment shown in FIG. 2, the removal plate has twice as many cavities as feed devices which form two groups of cavities that form be filled with the foaming plastic one after the other

BEZUGSZE1CHENLISTE

Tool, 3, 4 feed device

Cavity, foam cavity, 7 mold nest

Werkzeugtrenπebeπe

Cork 0 removal plate 1 cover plate 2 cooling channels 3 ejection device 4 foam cavity 5, 15 'door plates 5 ", 15'" cover or cooling plate 6 tool element 7, 17 ', 17 "cavity plates, removal plates 8 plastic foam 9, 20 tool element 1 band 2 conveyor belt 3 cavitation plate 4 convex bottom 5, 26 cavities

Claims

PATENT CLAIMS

Process for the production of injection molded parts from plastic foam (18), which comprises the steps

Introducing foaming plastic (18) into a mold cavity (6, 7) with the aid of a feed device (2, 3, 4),

Separating the feed device (2, 3, 4) from the mold cavity (6 7) and foaming the plastic foam (18) in a foam cavity (5, 14) after separating the feed device (2, 3, 4) from the mold cavity (6, 7)

Method according to claim 1, characterized in that the plastic foam (18) is cooled in the foam cavity

Method according to claim 1 or 2, characterized in that the foaming of the plastic foam (18) takes place in a foam cavity (5) contained in the mold cavity (6, 7)

Method according to claim 1 or 2, characterized in that the foaming of the plastic foam (18) takes place in a foaming cavity (14) which is separate from the mold cavity (6, 7)

Method according to one of claims 1 to 4, characterized in that the foam cavity is at least temporarily closed during the foam process

Method according to one of claims 1 to 5, characterized in that a plastic cork (9) is produced as the molded casting

Device for producing injection molded parts from plastic foam (18) with at least one foam cavity (14) for receiving the plastic foam (18) and at least one feed device (2, 3, 4) for feeding the plastic foam (18), the foam cavity (14 ) is provided for receiving the plastic display (18) until the foam casting is completely foamed, characterized in that at least two foam cavities (14) are assigned to each supply device (2, 3, 4)

Device according to claim 7, characterized in that a mold cavity (6, 7) with a

Cavity (5) is provided for receiving the plastic foam (18) fed by the feed device (2, 3, 4), the mold cavity (6, 7) and the feed device (2, 3, 4) relative to one another between an open position, in which the cavity (5) is accessible from the outside, and a closed position in which the cavity (5) from the feed device (2, 3, 4) is movable, that a removal plate (10), in which the foam cavity (14) is arranged, is provided, for receiving the plastic foam contained in the cavity (5) of the mold cavity (6, 7) (18) can be moved in the open position between the mold cavity (6, 7) and the feed device (2, 3, 4), and that means (7) for transferring the plastic foam (18) from the cavity (5) into a foam cavity (14) are provided

Apparatus according to claim 8, characterized in that the cavity (5) of the mold cavity is substantially in the form of a blind hole and has a convex bottom

Apparatus according to claim 8 or 9, characterized in that a cover plate (11) is provided for closing the foam cavity (14)

Device according to one of claims 8 to 10, characterized in that an ejection device (13) is provided for ejecting the completely foamed injection molded part from the foam cavity (14)

Device according to one of claims 8 to 10, characterized in that the foam cavity (14) has the shape of a blind hole

Apparatus according to claim 7, characterized in that a cavitation plate (17) with at least one through hole and a tool element (16) is provided, the feed device (2, 3, 4) and tool element (16) relative to one another between an open position and one Closing position are movable and the Kavitatenpieatte (17) in the

Opening position between the feed device (2, 3, 4) and the tool element (16) is movable and the feed device (2, 3, 4), tool element (16) and cavitation plate (17) are designed and arranged in such a way that tool element (16) and In the closed position, feed device (2, 3, 4) close the through hole from both sides and thereby form the foam cavity (14)

Apparatus according to claim 13, characterized in that at least one cooling plate (15, 15 ', 15 ", 15'"), preferably two cooling plates (15, 15 ', 15 ", 15"') are provided, which are designed and movable in this way are that it closes at least one side of the bore, preferably both sides of the bore, if the cavity plate (17) is not arranged between the feed device and the tool element

Device according to claim 13 or 14, characterized in that a plurality of cavitation plates (17, 17 ', 17 ") are provided Apparatus according to claim 15, characterized in that at least one cover plate (15 ") is provided which can be moved between two cavitation plates (17, 17 ') such that it covers one side of the at least one bore of each cavitation plate (17, 17 ') closes

Device according to claim 7, characterized in that a closing element (15) is provided for closing the foam cavity (14) after the plastic foam (18) has been introduced into the foam cavity (14) with the aid of the feed device (2, 3, 4) is

Device according to one of claims 7 to 17, characterized in that the device (1) is intended to foam the plastic foam (18) in at least one foam cavity (14), and at the same time non-foam plastic foam (18) with the aid of the feed device (2 , 3, 4) in at least one other foam cavity (14)

Apparatus according to claim 18, characterized in that the apparatus (2) is designed as a revolving tool (21), at least two foaming cavities (14) being circumferentially arranged such that they are sequential with the aid of the feed device (2, 3,

4) filled with plastic foam (18) and can be freed from the molded casting (9) after complete foaming

Apparatus according to claim 19, characterized in that there is also a circulation device (22) with at least two closing elements (15) for closing the at least two

Foam cavities (14) are provided after the foam cavities (14) have been filled with plastic foam (18)

Apparatus according to one of Claims 7 to 20, characterized in that a plurality of supply means (2, 3, 4) and a plurality of foam cavities (14) are provided, the number of foam cavities (14) being an integral multiple of the number of the feed devices (2, 3, 4)