TW201536507A - Injector for the charging of material to a mold and process for the production of moldings from foamed polymer particles - Google Patents

Abstract

The invention relates to an injector for the charging of material to a mold (11) for the production of moldings from foamed polymer particles (1), comprising a duct (5) for the introduction of foamed polymer particles (1), a feed neck (9), and an injector piston (29), where the feed neck (9) adjoins the duct (5) for the introduction of foamed polymer particles (1), and where the injector piston (29) has, at its end facing toward the mold (11), a cross-sectional area (31) which corresponds to the cross-sectional area at the outlet (21) of the feed neck (9) into the mold (11), and the movement of the injector piston (29) is such that foamed polymer particles (1) can be forced from the feed neck (9) with the aid of the injector piston (29) into the mold (11), wherein the feed neck (9) has at least one aperture (19) through which compressed gas can be introduced into the feed neck (9). The invention further relates to a process for the production of a molding from foamed polymer particles.

Description

Syringe for filling material to mold and method for producing molded article from foamed polymer particles

The present invention relates to a syringe for filling a mold to a mold for producing a molded article from expanded polymer particles, comprising a pipe for introducing foamed polymer particles, at least one pipe for introducing a gas, and a feed neck And a syringe piston, wherein the feed neck abuts a conduit for introducing foamed polymer particles, and a conduit for introducing a gas leads upstream of the feed neck to a conduit for introducing foamed polymer particles, and wherein The syringe piston has a cross-sectional area corresponding to the cross-sectional area of the feed neck at its end toward the mold, and moves the syringe piston such that polymer particles can be forced into the mold from the feed neck by the syringe piston . The invention further relates to a method of producing a molded article from expanded polymer particles.

Molded articles made from expanded thermoplastic polymer particles have many possible applications: such molded articles can be used as support, seat cushions, mattresses or other outsole by way of example. By introducing the foamed polymer particles into the mold, the respective molded articles are steam-treated or steam-heated in the mold in accordance with the existing techniques of the currently used molding machine in such a manner that the outer sides thereof are melted with each other to produce the respective molded articles.

To add material to the mold for producing the molded article from the foamed thermoplastic polymer particles, a syringe is currently used to push the foamed polymer particles into the mold via a syringe by means of a gas stream. For this purpose, the syringe abuts the feed neck on the mould. Once the mold has been filled, the syringe plunger is moved into the feed neck, in such a way that particles contained in the feed neck are forced into the mold in. Prior art syringes have the disadvantage that some of the expanded polymer particles accumulated in the feed neck cannot be forced into the mold by the syringe piston. Undesirable protrusions are thus produced on the molded article.

Can be used to fill materials to molds for production from foamed thermoplastic polymer pellets The syringe of the molded article is described by way of example in EP-A 1 813 409. This has a central conduit for introducing foamed polymer particles and also has an annular gap that allows air to be blown into the system. Once the material has been filled into the mold, steam is introduced using a second annular gap. Furthermore, the syringes described in the document do not permit the minimization of the amount of foamed polymer particles in the feed neck, in such a way that when the foamed polymer particles are forced into the system by the syringe piston, they are not on the molded article. A protrusion is generated.

Accordingly, it is an object of the present invention to provide a syringe and a thermoplastic from foaming The method of producing a molded article from polymer particles, which permits the manufacture of a molded article having no protrusion at a position adjacent to the syringe.

Producing a molded article from foamed polymer particles via a filling material to a mold This object is achieved by a syringe comprising a conduit for introducing foamed polymer particles, a feed neck and a syringe piston, wherein the feed neck abuts a conduit for introducing foamed polymer particles, and wherein the syringe piston is in A cross-sectional area corresponding to a cross-sectional area of the feed neck toward the end of the mold, and moving the syringe piston such that polymer particles can be forced into the mold from the feed neck by the syringe piston, wherein the feed The neck has at least one orifice through which compressed gas can be introduced into the feed neck.

This object is further achieved by a method of producing a molded article from expanded polymer particles, the method comprising the steps of: (a) filling a foamed polymer particle to a mold by means of a syringe for filling a material to a mold, wherein Introducing the foamed polymer particles into a pipe into which the foamed polymer particles are introduced, And after the material has been charged to the mold, the compressed gas is introduced into the feed neck via the orifice for introducing the compressed gas, and (b) the foamed polymer particles still contained in the feed neck are pushed to And in the mold, once the mold has been completely filled, the mold is closed by moving the syringe piston in the direction of the mold, and (c) heating the foamed polymer particles such that the particles become bonded to each other to produce a molded article .

Introducing the compressed gas into the feed neck avoids any of the following situations: where the feed neck also becomes completely filled after the mold has been filled. The resulting gas stream liquefies the foamed polymer particles in the feed neck and, once the mold has been completely filled, causes the expanded polymer particles to flow countercurrently into the syringe. This avoids any situation in which the amount of foamed polymer particles accumulated in the feed neck is so large that after the foamed polymer particles have been forced into the mold from the feed neck by the syringe piston, A protrusion is formed on the molding assembly. The syringe piston thus may form a seal that is flush with the inner wall of the mold, in such a way that a smooth surface can be achieved on the desired molding.

In one embodiment, the syringe has at least one conduit intended to be used to introduce a gas and which leads upstream of the feed neck to a conduit for introducing foamed polymer particles. If a conduit for introducing at least one gas is included, it is possible to assist the filling procedure by introducing a compressed gas via a conduit for introducing at least one gas. It is furthermore advantageous if the compressed gas is introduced via at least one conduit for introducing a gas after the material has been charged to the mold. Alternatively, however, it is also possible to transfer the compressed gas into the feed neck only via the orifice for introducing the compressed gas.

The purpose of this document is to introduce a countercurrent in a conduit for introducing foamed polymer particles via an orifice for introducing compressed gas into the feed neck and optionally introducing a compressed gas via at least one conduit for introducing gas. No additional foamed polymer particles are transported in the direction of the mould and accumulate in the feed neck region. When the polymer particles are forced into the system by the syringe piston, this condition will cause the undesired protrusions on the mold to expand further.

It is also preferred to carry out via a tube for introducing foamed polymer particles by means of a gas The channel transports the foamed polymer particles. The foamed polymer particles are thus blown into the mold by a gas via a pipe for introducing the foamed polymer particles.

Any desired gas that is inert to the polymer used can be used via a syringe The foamed polymer particles are transferred to a mold. Examples of suitable gases are rare gases, nitrogen, carbon dioxide, steam and air. Nitrogen, steam or air is preferred and air is a particularly preferred gas. The compressed gas is preferably the same as the gas used to transport the foamed polymer particles, and the compressed gas is injected into the feed neck via the orifice for introducing the gas at the end of the filling process, and is optionally injected for use Introduced into the gas pipeline. Compressed air is particularly preferred herein. The gas for transporting the foamed polymer particles and the pressure introduced through the orifice for introducing the compressed gas in the feed neck and optionally introduced by the gas for introducing the gas are preferably at a pressure higher than atmospheric pressure of 0 bar. To the extent of 8 bar.

Any suitable method can be used to heat the foamed polymer that is added to the mold The granules are such that the granules become viscous to produce a molded article. It is especially preferred that for this purpose a hot gas stream is passed through the mould. Suitable gases are any desired gas which is inert to the polymer used. In particular, steam is used as a gas.

If a syringe is used, it is also introduced via a syringe for bonding foamed polymer particles. The gas (specifically, the steam), as in the case of the use of a syringe as described in the example of EP-A 1 813 409, by means of which it is possible to perforate the syringe piston with a pore diameter smaller than the diameter of the foamed polymer particles, This way the steam can flow into the mold via the holes in the syringe piston. Of course, it is also possible to provide a separate input device for the steam. For this purpose, any desired input device known to those skilled in the art can be used, in particular, including devices of the type currently used to introduce steam into the mold.

In order to obtain sufficient liquefaction of the foamed polymer particles in the feed neck, for pressing The favorable orientation of the condensing gas introduced into the orifice in the feed neck is such that the introduced compressed gas has a perpendicular to the feed The velocity component of the axis of the neck. The velocity component perpendicular to the axis of the feed neck creates a cross-flow that causes the foamed polymer particles to liquefy. In order to obtain a velocity component perpendicular to the axis of the feed neck, the orientation of the orifice for introducing the compressed gas may be perpendicular to the axis of the feed neck or at any desired angle greater than 0° with respect to the axis of the feed neck. Preferably, the orientation of the orifice for introducing the compressed gas is in the range of 30° to 90°, in particular in the range of 75° to 90°, and in particular at an angle of 90°, That is, perpendicular to the axis of the feed neck.

If the orifice for introducing the compressed gas is oriented relative to the axis of the feed neck At an angle less than 90°, the orifice can be tilted in any desired direction. However, the inclination parallel to the axis of the feed orifice is prioritized, and the inclination of the injection of the compressed gas in the direction of the mold is highly preferred.

By means of orientation in the direction of the mould, by means of introducing compressed gas The compressed gas introduced by the orifice assists the filling procedure. In this case, it is also preferred to introduce the compressed gas during the entire filling procedure by means of an orifice in the feed neck for introducing compressed gas. When the orientation of the orifice for introducing the compressed gas is in the direction of the reinjector, it is advantageous to introduce a compressed gas into the feed neck by means of an orifice for introducing a compressed gas until the mold has been filled so that it is completely The foamed polymer particles are not blown away from the mold until the mold is filled. If the compressed gas is introduced at the same time by means of all the orifices, it is alternatively possible to change the speed of the compressed gas or in particular to change the pressure. The pressure of the gas in the injector is then higher during the filling procedure, however after the filling procedure, the pressure of the gas introduced into the feed neck by means of the orifice for introducing the compressed gas is increased to such an extent that there is no longer any Sufficient free space blows the particles back into the syringe in a direction opposite to the direction of the delivery process.

Even the orifice for introducing compressed gas into the feed neck is perpendicular to the feed orifice The axis, advantageously, delays the injection of compressed gas until the mold has been filled, or alternatively, once the mold has been completely filled, the pressure or volumetric flow rate of the compressed gas injected into the feed neck is increased, and the purpose of this document is to avoid Do not completely fill the mold or excessively lengthy filling procedures. However, when the orientation of the orifice for introducing compressed gas into the feed neck is perpendicular to the axis of the feed orifice, another possibility is to also inject compressed gas during the filling procedure.

For producing a uniform flow in the feed neck and thus uniformly filling the material to the mold In order to achieve consistent product quality, it is further preferred to provide at least two orifices for introducing compressed gas into the feed neck, wherein the configuration has orifices evenly distributed over the periphery of the feed neck.

An independent compressed gas supply line may be provided for each hole, and the purpose is to have a complex Several orifices are supplied with compressed gas for the introduction of compressed gas orifices. However, it is preferred to feed all of the orifices using a common supply line. For this purpose, it is possible by way of example to connect at least two orifices for introducing compressed gas into the feed neck to a gas distribution ring surrounding the feed neck. The compressed gas is then supplied by means of a gas distribution ring for the individual orifices into which the compressed gas is introduced. The gas distribution ring has at least one connection by means of which a compressed gas can be introduced to supply a compressed gas to the gas distribution ring.

To prevent the syringe piston from interfering with foaming polymerization during the filling of the material to the mold For the purpose of the flow of particles, it is advantageous to design the syringe such that when the syringe piston is at rest, i.e., during the filling of the foamed polymer particles to the mold, the syringe piston is located at the point where the foamed polymer particles are introduced. The location. The point of introduction of the foamed polymer particles herein can be laterally located on the syringe by way of example. If the diameter of the conduit for introducing the expanded polymer particles is larger than the diameter of the feed neck, it is alternatively possible that the expanded polymer particles flow around the syringe piston during the filling of the material to the mold. However, the position of the syringe piston is preferably selected in such a way that the foamed polymer particles are introduced in front of the syringe piston in such a way that it does not have to flow around the syringe piston.

In a specific example, it is designed to introduce an injection at the end of the filling process. The gas is such that a flow is generated in a direction opposite to the direction in which the expanded polymer particles are transported so that no additional foamed polymer particles are transported in the direction of the mold, so that the conduit for introducing the gas A conduit for introducing foamed polymer particles is coaxially surrounded. In this case, it is especially preferred to inject gas at the end of the pipe by means of an annular gap into the pipe for introducing the foamed polymer particles. Uniform flow is thus achieved in a manner that prevents the formation of dead volume that can be accumulated by any of the foamed polymer particles.

Alternatively, it is also possible for at least two conduits for introducing gas and for The pipe into which the foamed polymer particles are introduced is operated in parallel, wherein the configuration has a pipe for introducing a gas uniformly distributed around a pipe for introducing the foamed polymer particles. A configuration in which the conduit for introducing the gas is evenly distributed around the conduit for introducing the foamed polymer particles, in addition, produces a uniform flow in order to prevent the formation of a dead volume which the foamed polymer particles can accumulate.

In order to permit the foamed polymer particles to bond in the mold for heating, for example via The molded article is produced by injection of steam, and preferably, the expanded polymer particles comprise a thermoplastic polymer. The thermoplastic polymer used to foam the thermoplastic polymer particles can be any desired thermoplastic.

It is especially preferred that the foamed thermoplastic polymer is selected from expanded polypropylene (expanded polypropylene; EPP), expanded polyethylene (EPE), expanded polystyrene (EPS) and expanded thermoplastic polyurethane (ETPU) and mixtures of such polymers and A copolymer comprising monomer units of such polymers. Most preferably, the expanded thermoplastic polymer is an expanded thermoplastic polyurethane.

The foamed thermoplastic polymer can comprise any of the materials used to process thermoplastic polymers. Fillers and additives. Those skilled in the art will be aware of suitable fillers and additives.

The foamed thermoplastic polymer can thus comprise (illustrated by way of example) a lubricant, plastic Chemicals, UV stabilizers, colorants, pigments, and any other additives typically added to the polymer. Fillers or reinforcing materials may also be included, examples being fibers, in particular short fibers.

In one embodiment, the foamed thermoplastic polymer comprises internal or external lubrication Agent. This is usually added in the form of an additive during the production of the foamed thermoplastic polymer particles. internal Or an external lubricant adheres to the surface of the individual foamed thermoplastic polymer particles and thus assists in lubrication, thus permitting prevention of agglomeration.

The average diameter of individual foamed thermoplastic polymer particles is usually from 1 mm to 10 Within the range of mm, specifically in the range of 1.5 mm to 6 mm. The bulk density of the expanded thermoplastic polymer particles is preferably in the range of from 5 g/l to 600 g/l, more preferably in the range of from 10 g/l to 500 g/l, and specifically from 15 g/l to 200 g/l. Within the scope.

The shape of the foamed thermoplastic polymer particles may be, for example, a cylindrical shape or a spherical shape or an ellipsoidal shape as needed. It is especially preferred that the foamed thermoplastic polymer particles have a spherical shape.

The drawings depict one specific example of the invention, which is explained in more detail in the following description.

1‧‧‧Foamed polymer particles

3‧‧‧ airflow

5‧‧‧ Pipes

7‧‧‧Syringe

9‧‧‧Feed neck

11‧‧‧Mold

13‧‧‧ Pipes

15‧‧‧ annular gap

17‧‧‧Cone diameter reduction

19‧‧‧孔口

21‧‧‧Export

23‧‧‧ gas distribution ring

25‧‧‧Connect

29‧‧‧Syringe piston

31‧‧‧ cross-sectional area

Figure 1 illustrates the first step of a method of producing a molded article from expanded polymer particles, Figure 2 illustrates a second step of a method of producing a molded article from expanded polymer particles, and Figure 3 illustrates the particles from a foamed polymer. The third step of the method of producing a molded article, and Figure 4, shows the fourth step of the method of producing a molded article from the expanded polymer particles.

Figure 1 depicts the first step of a method of producing a molded article from expanded polymer particles.

In order to produce a molded article from the foamed polymer particles 1, the foamed polymer particles 1 are introduced into the center pipe 5 of the syringe 7 by means of the gas stream 3. Any suitable gas inert to the polymer can be used as the gas herein. Examples of suitable gases are air, nitrogen or steam, in particular air.

The syringe 7 contains a feed neck 9 which connects the syringe 7 to the mold 11. The foamed polymer particles 1 are pushed into the mold 11 via the body neck 9 by means of the gas stream 3.

In the specific example depicted herein, there is an annular duct 13 that is surrounded by The heart duct 5 is additionally introduced with gas via an annular duct. For this purpose, the annular duct 13 leads to an annular gap 15 at the end of the central duct 5. In the particular example depicted herein, the annular duct 13 has a tapered diameter reduction portion 17 at its end in the region of the annular gap 15, wherein the diameter is reduced to the diameter of the feed neck 9. Coexisting with the tapered diameter reduction portion 17 depicted herein, of course, another possibility is that the diameter reduction portion is designed to have any other desired geometry. By way of example, discontinuous diameter reduction in one or more steps is therefore possible. Alternatively, the shape of the reduced diameter portion may be concave or convex depending on its radius; it may also be elliptical, parabolic or hyperbolic. It may also be a mixed shape.

The airflow introduced via the annular duct 13 assists the filling procedure until it is completely filled Mold 11. The gas passing through the annular duct 13 is preferably the same as the gas for transporting the foamed polymer particles 1 via the central duct 5.

In the feed neck 9 of the present invention, there is at least one for introducing a compressed gas The orifice 19 is. Preferably there are a plurality of orifices 19 arranged to introduce a compressed gas, wherein the configuration may have any desired distance between the orifices or may have orifices equidistant from each other. Priority is given to the equidistant arrangement of the orifices 19, and in this case it is preferred that each of the orifices is at the same axial distance from the outlet 21 of the feed neck 9 and that the configuration is at the orifice There is an equal distance between 19. It is also possible to position the orifice 19 at a different axial distance from the outlet 21 of the feed neck 9 by offset relative to each other. All orifices 19 are of the same axial distance from the outlet 21 of the feed neck 9 or have a different distance from the outlet 21 of the feed neck 9, in particular depending on the length of the feed neck.

Preferably, the compressed gas is introduced into the orifice 19 by means of the gas distribution ring 23. in. The gas distribution ring 23 herein surrounds the inner wall 15 of the feed neck 9, and one end of each of the orifices 19 leads to the gas distribution ring 23. The compressed gas is thus uniformly supplied to all of the orifices 19. Alternatively, it is of course also possible to connect only the individual orifices 19 to the gas distribution ring 23 and to supply the other orifices 19 with compressed gas or to supply compressed gas to each of the other orifices 19 by means of the second gas distribution ring. . The compressed gas introduced here by means of the orifice 19 is likewise preferably used with The gas transporting the foamed polymer particles is the same.

The compressed gas is preferably supplied to the gas distribution ring 23 by means of a gas connection 25. In conjunction with a single gas connection 25 as depicted herein, another possibility is to provide a plurality of gas connections at the gas distribution ring 23. However, only one gas connection 25 is preferred.

If no gas distribution ring 23 is used to supply compressed gas to the orifice 19, then It is necessary to provide a gas connection to each of the orifices 19. However, this increases the cost of the device, and therefore it is preferred to connect all of the orifices 19 to the gas distribution ring 23 and in this way achieve a supply of compressed gas.

During the filling of the material to the mould 11, the annular duct 13 and the orifice can be used 19 introduces a gas. Alternatively, it is also possible to fill the material only by using a gas stream for transporting the foamed polymer particles. In this case, the annular gap 15 and the size of the orifice 19 are particularly advantageous so that the non-foamed polymer particles can be blown into the annular duct 13 or the orifice 19. For this purpose, it is possible to use a grid having a mesh width smaller than the smallest diameter of the foamed polymer particles to block the annular gap 15 and the orifice 19 by way of example. Alternatively, it is also possible to produce an annular gap having a gap width smaller than the smallest diameter of the foamed polymer particles, and to manufacture the orifice 19 having a correspondingly smaller orifice diameter. Preferably, however, gas is injected into the conduit by means of the annular gap 15 and the orifice 19 throughout the filling procedure to prevent the expanded polymer particles from being transferred into the annular gap 15 or orifice 19.

It is also possible to provide individual tubes of the central duct 5 directly before the feed neck 9 The road replaces the annular duct 13. In such a situation, it is advantageous to provide a plurality of conduits, preferably equidistantly disposed around the central conduit. In a further variant, it is also possible to provide an orifice which is supplied with compressed gas or which is supplied with compressed gas by means of a common gas distributor instead of the annular gap 15.

Figure 2 depicts the second step of the method of the present invention.

In the step depicted in Figure 2, the mold 11 has been completely filled with foamed polymerization. Particle 1. By means of the gas flow via the annular duct 13 and the annular gap 15, a countercurrent is generated in the central duct 5 in such a way that no additional foamed polymer particles 1 are uploaded in the direction of the feed neck 9 lose. In addition, the foamed polymer particles are blown back from the feed neck 9 into the center duct 5 by the compressed gas injected through the orifice 19 due to the absence of additional space in the mold 11. This prevents the foamed polymer particles 1 from accumulating in the feed neck, which will form protrusions on the molded article during the manufacture of the molded article via the melting of the individual polymer particles.

In order to blow the foamed polymer particles back from the feed neck to the central pipe, necessary Yes, the orifice 19 is designed such that the compressed air injected via the orifice 19 has a velocity component perpendicular to the axis 27 of the feed neck 9. For this purpose, it is necessary that the orifice 19, usually in the form of a hole, exhibits an angle greater than 0° with respect to the central axis 27 of the feed neck 9. It is especially preferred that, as depicted herein, the orifice 19 runs perpendicular to the axis 27 of the feed neck 9 in such a way that at the exit from the orifice 19, the only velocity component is perpendicular to the axis 27 of the feed neck 9. . By way of example, the gas flow for transporting the foamed polymer particles 1 or otherwise by the gas flow through the plurality of orifices 19 collides with each other or with the wall of the feed neck 9 with respect to the orifice 19, causing The deflection of the air flow introduced via the aperture 19.

Figure 3 depicts the third step of the method of the present invention.

Once the filling material has been completed to the mold 11, via the center pipe 5 in the mold 11 The syringe plunger 29 is moved in the direction. During the filling of the foamed polymer particles 1 to the mold 11, as depicted in Figures 1 and 2, the position of the syringe piston 29 is in a rest position not depicted herein. The position of the rest position herein is preferably after the point at which the foamed polymer particles 1 are introduced into the syringe 7, so that the syringe piston 29 does not destroy the flow of the expanded polymer particles 1 into the mold 11.

The compressed gas flows through the orifice 19 to keep the feed neck 9 free of foamed polymer particles. Granule 1. Furthermore, the flow of compressed gas through the orifice 19 ensures that the non-foamed polymer particles 1 are transported back from the mould 11 into the feed neck 9 and thus back into the syringe 7. Therefore, the optimum filling of the mold 11 is maintained. The foamed polymer particles 1 still located in the central duct 5 are blown back by the flow of the gas through the orifice 19 in the feed neck and via the annular gap 15. It is therefore possible to maintain the central duct 5 substantially in a manner that permits the syringe piston 29 to move into the feed neck 9 without damaging the foamed polymer particles 1. It does not contain foamed polymer particles 1.

The syringe piston 29 herein is preferably designed such that the cross-sectional area of the tip 31 corresponds to The cross-sectional area of the feed neck 9 into the outlet 21 of the mold 11. It is therefore possible to use the syringe piston 29 to close the inlet 21 of the feed neck 9 into the mold 11 to form a molded article. Furthermore, the design of the end 31 of the syringe piston 29 is advantageous such that this end provides a continuous inner surface of the mold 11, thus avoiding any discontinuities in the shape of the molded article at the point of filling.

The syringe plunger 29 is moved into the syringe 7 until it closes the feed neck 9 Enter the outlet 21 of the mold 11. This is depicted as the fourth step in Figure 4.

In order to prevent the polymer particles 1 from subsequently flowing further into the central pipe 5, The gas is introduced by means of the annular duct 13 and the annular gap 15. When the syringe piston 29 is in its forward end position and encloses the inlet 21 of the feed neck 9 into the mold 11, the gas thus flows away from the mold via the central conduit 5 and thus the central conduit 5 is essentially free of foamed polymer particles 1 In this way, once the production of the molded article has been completed and the molded article can be demolded, the non-foamed polymer particles 1 can block the path of the syringe piston 29 when moving back to the syringe plunger 29.

In order to complete the production of the molded article, once the syringe piston 29 has reached its forward direction The terminal position heats the surface of the foamed polymer particles 1 until the particles become soft and can melt with each other. For this purpose, it is possible to transfer hot gases, in particular steam, via a mould 11 by way of example. Once the foamed polymer particles 1 have been bonded to produce a molded article, the mold 11 is opened and the molded article can be removed. At the same time, the syringe piston 29 is moved back to its rest position in such a way that the process can be repeated once the molded article has been removed and then the device has been closed.

1‧‧‧Foamed polymer particles

5‧‧‧ Pipes

7‧‧‧Syringe

9‧‧‧Feed neck

11‧‧‧Mold

13‧‧‧ Pipes

15‧‧‧ annular gap

19‧‧‧孔口

21‧‧‧Export

23‧‧‧ gas distribution ring

25‧‧‧Connect

29‧‧‧Syringe piston

31‧‧‧ cross-sectional area

Claims (14)

A syringe for filling a material to a mold (11) to produce a molded article from the foamed polymer particles (1), comprising a pipe (5) for feeding the foamed polymer particles (1), a feed neck ( 9) and a syringe piston (29), wherein the feed neck (9) adjoins the conduit (5) for introducing foamed polymer particles (1), and wherein the syringe piston (29) faces the mold ( 11) has a cross-sectional area (31) corresponding to the cross-sectional area of the feed neck (9) at the outlet (21) of the mold (11), and moves the syringe piston (29) so that The syringe piston (29) forces the foamed polymer particles (1) from the feed neck (9) into the mold (11), wherein the feed neck (9) has at least one orifice (19) via The orifice introduces compressed gas into the feed neck (9). A syringe according to claim 1, wherein the orifice (19) for introducing compressed gas into the feed neck (9) is oriented such that the introduced compressed gas has a perpendicular to the feed neck (9) The velocity component of the axis. A syringe according to claim 1 wherein there are at least two orifices (19) arranged to introduce compressed gas into the feed neck (9), wherein the configuration has a uniform distribution over the feed neck The apertures (19) on the perimeter of (9). A syringe according to claim 3, wherein there are at least two orifices (19) for introducing compressed gas into the feed neck (9) to a gas distribution ring surrounding the feed neck (9) (23) connection. A syringe according to claim 4, wherein the gas distribution ring (23) has at least one connection (25) by means of which a compressed gas can be introduced. A syringe according to claim 1 which additionally comprises at least one conduit (13) for introducing a gas and leading to the conduit for introducing foamed polymer particles upstream of the feed neck (9) (5) ). A syringe according to claim 6 wherein the conduit for introducing a gas (13) The pipe (5) for introducing the foamed polymer particles (1) is coaxially surrounded. A syringe according to claim 6 wherein at least two of the conduits for introducing a gas run in parallel with the conduit (5) for introducing the foamed polymer particles (1), wherein the configuration has a circumference for introducing the hair The tubes (5) of the blister polymer particles (1) are uniformly distributed for the introduction of the gas. A method for producing a molded article from a foamed polymer particle (1), comprising the steps of: (a) supplying a material to the mold by means of any one of items 1 to 8 of the patent application; The syringe (7) of (11) is filled with the foamed polymer particles (1) to the mold (11), wherein the foaming is introduced via the pipe (5) for introducing the foamed polymer particles (1) Polymer particles (1), and after the material has been charged to the mold (11), compressed gas is introduced into the feed neck (9) via the orifice (19) for introducing compressed gas, (b) Pushing the foamed polymer particles (1) still contained in the feed neck (9) into the mold (11) and once the mold (11) has been completely filled, via the mold (11) The syringe piston (29) is moved in the direction to close the mold (11), and (c) the foamed polymer particles (1) are heated so that the particles become bonded to each other to produce the molded article. The method of claim 9, wherein the steam is passed through the mold (11) in order to heat the foamed polymer particles (1) in the step (c). The method of claim 9, wherein the foamed polymer particles (1) comprise a thermoplastic polymer. The method of claim 11, wherein the thermoplastic polymer is selected from the group consisting of expanded thermoplastic polyurethanes, expanded polypropylene, and mixtures of such polymers and copolymers comprising monomeric units of such polymers. The method of claim 9, wherein during the entire filling procedure in step (a), by means of the conduit (13) for introducing a gas and by means of introducing a compressed gas The orifices (19) introduce a gas. The method of claim 9, wherein the gas system is selected from the group consisting of air, nitrogen, and steam.