DE102019002052A1 - Device for evacuating gases with a sieve structure - Google Patents

Abstract

A device (100) for evacuating gases comprises a body (110) with a passage (120) for evacuating gases, at least a part of the passage (120) being filled with a structure (130) which allows gases to pass through and prevents the passage of solids and the structure (130) is fixed to the body (110).

Description

The invention relates to a device for discharging gases and to a method for producing such a device. In particular, the invention relates to degassing inserts for degassing extrusion devices and their manufacture.

The use of degassing devices to remove gases emerging from machined solids or viscous liquids is known. For example, in extrusion devices, gases are withdrawn from the plastically deformable extrusion compound while it is being conveyed through the extrusion device. With conventionally used degassing devices, there is a risk that in addition to the gases to be discharged, material from which the gases emerge will also get into the degassing device. Particularly in the case of hot or high pressure materials, it can happen that material is torn together with the gas into the degassing device. In addition, it is possible that when the material is guided past the degassing device, it stagnates at a passage of the degassing device or settles there.

This can lead to the degassing device being clogged by the material, as a result of which the discharge of gas is impaired or prevented. This can affect the stability of manufacturing processes and the quality of the material to be degassed. In addition, materials deposited in the degassing device can age and react chemically as a result, which can result in corrosive media that damage machine components.

It is the object of the present invention to specify a device for discharging gases in which the above-mentioned problems do not occur. A degassing device is to be specified which prevents gas and material to be degassed from entering the degassing device together.

This object is achieved with the subject matter of the independent claims.

A device for evacuating gases may, for example, comprise a body with a passage for evacuating gases, at least a part of the passage being filled with a structure that allows passage of gases and prevents passage of solids, and the structure on which Body is fixed.

As with conventional degassing devices, the passage serves to discharge gases. However, the passage through the filling with the structure is protected against the penetration of solids into areas behind the structure. The fixing of the structure on the body ensures that the structure does not shift in the passage under the pressure of the material to be degassed.

In this way it can be ensured that gas discharged by the device is separated by means of the structure from the material from which the gas is discharged.

The structure can be inextricably linked to the body, i.e. a permanent bond has been made between the structure and the body that cannot be broken without damaging the body, the structure, or both. This reliably ensures that the structure does not shift and thus reliably prevents the passage of the degassing device from being clogged by penetrating material. For example, the structure can be permanently connected to the body by gluing it to the body.

The structure can also consist of the same material as the body and be formed in one piece with the body. Body and structure therefore merge seamlessly, they are made from one piece and form a single element. This provides a particularly reliable connection between body and structure.

The structure may comprise a screen member integral with the body, i. the structure is in the form of a sieve with a certain mesh size through which gas but no solids can penetrate.

The structure can be arranged in a region of the passage adjacent to a surface of the body. The structure is thus placed near the edge of the device in the passage, e.g. 1 mm, 5 mm or 10 mm from a surface of the body. This prevents material from penetrating into the interior of the passage or from sticking to an edge of the passage or being deposited there, since penetration is prevented by the structure. In particular, a slow build-up of material due to abrasion can also be prevented if the structure is flush or essentially flush with a surface of the body that is in contact with the material to be degassed. This guarantees a particularly reliable separation of gas and material to be degassed.

The above-described body and the structure can be produced together additively, for example by means of a 3D printing process known per se. So the structure becomes additive Buildup of the body is created directly in the passage. In other words, instead of a full-area, continuous opening, a network of channels for the discharge of gas is formed in one area of the passage. This network can have any additive manufacturing shape that is capable of preventing the passage of solids. The network can take up the entire passage. The thickness of the network in the direction of flow of the gas can, however, also be limited to a minimum thickness below which the network would no longer be mechanically stable.

For example, the network can have a sponge-like structure or consist of a mesh or a lattice structure with a predetermined mesh size. The mesh size can change both along the cross section of the passage and along the direction of flow of the gas. The mesh size can e.g. be narrow at the inlet of the passage and the structure can have a plurality of meshes there. This ensures that no solids can penetrate the structure. In the direction of flow of the gas, the meshes or the channels formed by them can widen and / or merge with one another in order to facilitate an outflow of the gas.

The additive manufacture of the degassing device thus makes it possible to produce filter structures that effectively separate the gases from the solids to be degassed and which could not be produced in a conventional manner. In addition, additive manufacturing allows the device to be manufactured in a cost-effective manner.

The device can be a degassing insert. As a result, the device is particularly suitable as a degassing device for extrusion devices.

The body and the structure can be made of material that is heat resistant, preferably up to a temperature between 150 ° C and 200 ° C. This also allows the device to be used for degassing hot materials, such as those used e.g. occur during the extrusion of plastics.

An extrusion device for producing an extrudate from an extrusion compound can have means for conveying the extrusion compound and a device as described above. The device can be arranged in the extrusion device in such a way that gases can be removed from the extrusion compound via the passage of the device. In such an extrusion device, e.g. for extruding plastics, it is possible to reliably prevent degassing devices from being clogged or clogged by extrusion material.

The extrusion device can furthermore comprise a degassing dome into which the device discharges the gases, a closure of the degassing dome being connected to the device in such a way that the device can be removed from the extrusion device at the closure. This allows the degassing device to be easily removed from the extrusion device in order to service, clean or replace it.

A method for manufacturing a degassing device as described above comprises manufacturing the body and the structure of the device by means of additive manufacturing. As a result, degassing devices can be produced in a cost-effective manner which have the above advantages.

According to a further aspect, a method for producing a degassing device is provided, comprising the steps of: creating a data record which depicts the degassing device as described above; and storing the data set on a storage device or server. The method can further include: inputting the data record into a processing device or a computer which controls a device for additive manufacturing in such a way that it manufactures the degassing device depicted in the data record.

According to a further aspect, a system for additive manufacturing of a degassing device is provided, with a data set generating device for generating a data set which maps the degassing device as described above, a storage device for storing the data set and a processing device for receiving the data set and for controlling a device in this way additive manufacturing that it manufactures the degassing device shown in the data set. The storage device can be a USB stick, a CD-ROM, a DVD, a memory card or a hard disk. The processing device can be a computer, a server, or a processor.

According to a further aspect, a computer program or computer program product is provided, comprising data records which, when the data records are read in by a processing device or a computer, causes them to control a device for additive manufacturing in such a way that the device for additive manufacturing is as described above Degassing device manufactures.

According to a further aspect, a computer-readable data carrier is provided on which the computer program described above is stored. The computer-readable data carrier can be a USB stick, a CD-ROM, a DVD, a memory card or a hard disk.

According to a further aspect, a data record is provided which maps the degassing device as described above. The data record can be stored on a computer-readable data carrier.

• 1A und 1B eine schematische Darstellung einer Vorrichtung zum Abführen von Gasen; und
• 2 eine schematische Darstellung eines Teils einer Extrusionsvorrichtung mit einer weiteren Vorrichtung zum Abführen von Gasen.

The present invention will be described in detail below with reference to the figures. This description should not be understood as restrictive but as exemplary. The invention is defined only by the subject matter of the claims. It shows:

• 1A and 1B a schematic representation of a device for discharging gases; and
• 2 a schematic representation of part of an extrusion device with another device for removing gases.

In the 1A and 1B is schematically a device 100 shown for the discharge of gases. It goes without saying that the illustration of the device 100 is only exemplary and not to scale and that the device 100 in their shape also from the schematic representation of the 1A and 1B may differ. The 1B Figure 3 shows a top view of the device 100 of the 1A . The 1A FIG. 3 shows a cross section of the device along the line AA of FIG 1 B .

The device 100 has a body 110 on. The body 110 is the essential component of the device 100 . The device 100 can, for example, only from the body 110 consist, that is, the shape of the body 110 also defines the shape of the device 100 . In the 1A and 1B is the body 110 shown as a cuboid. The body 110 but can also take any form that allows gas to be discharged through it as described below. For example, the body can 110 also be cylindrical or conical or have the shape of a flange or a nozzle.

The body 110 can consist of any substance that is sufficiently stable and chemically resistant to be suitable for degassing a certain material. The choice of material for the body 110 is therefore determined by the material to be degassed and / or the gases. Preferably the body 110 made of a metal or a durable plastic. The material of the body 110 can be used to manufacture the body 110 be suitable by means of additive manufacturing in 3D printing processes.

The body 110 can also be made of a heat-resistant material that can, for example, be exposed to temperatures between 150 ° C and 200 ° C or more without changing its properties. This enables the device to be used 100 for degassing heated materials, such as a heated, plastically deformable mass such as is used for the extrusion of plastic.

Through the body 110 leads a passage 120 through which gas can be discharged. The passage 120 extends completely through the body 110 , preferably between two different surfaces of the body 110 . The device 100 is positioned for degassing in such a way that the passage 120 is communicatively connected via an opening to a container in which the material to be degassed is contained. The device can do this 100 For example, it can be inserted into a hole provided for this purpose in the container wall or attached to a connection piece. Gas can then go through the passage 120 escape from the container.

In the 1A leads the passage 120 straight from bottom to top through the body 110 , ie gases can enter the passage from below 120 stream and bring him to the top of the body 110 leave again. It goes without saying, however, that the passage can take any shape that allows gas of a certain volume to be discharged. The passage preferably has a cross-sectional diameter between 1 cm and 5 cm, for example 4 cm.

Especially with additive manufacturing of the body 110 are the shape of the passage 120 no limits. Thus, the passage can also have an inclined, curved, and / or undulating course or the like with any desired cross-section, which can also change during the course. Also needs the passage 120 not two opposite sides of the body 110 connect. The passage 120 Rather, it can go through the body at will 110 run as long as a discharge of gas through the passage 120 is possible.

In the passage 120 there is a structure 130 that is permeable to gases but not to solids. The structure 130 can, for example, be a net or lattice structure whose mesh size does not allow the penetration of solids to be degassed. Passages through the structure that are passable for the gas 130 such as the meshes of a network structure can be arranged regularly. The structure 130 is then a sieve element or has one. However, the passages can also have an irregular distribution, such as in a sponge. The structure 130 can therefore be constructed in any shape that allows gas, but not solids, to pass through.

The structure 130 can be separated from the body 110 made, then into the passage 120 introduced and fixed therein in such a way that the structure 130 in a customary manner during a degassing process from the solid to be degassed onto the structure 130 applied pressure is not shifted out of position.

For example, a somewhat deformable structure 130 such as a wire mesh, a wire sponge, a plastic mesh or a plastic sponge, between corresponding projections provided for this purpose in the passage 120 be pinched. The structure 130 could then by applying appropriate force, which is above the forces occurring during the degassing, out of the passage again 120 be solved. The structure 130 but can also be inextricably linked to the walls of the passage 120 ie with the body 110 be connected. For example it is possible to structure 130 at a certain point in the passage 120 to stick. When manufacturing bodies individually 110 and structure 130 can structure 130 also made of materials other than the body 110 consist. However, these must have similar properties in terms of heat resistance as those for the body 110 materials used. Also need the materials for the structure 130 be sufficiently stable so as not to be deformed by the effects of the solid to be degassed.

Preferably the structure is 130 made of the same material as the body 110 produced and connected to this in one piece or integrally. body 110 and structure 130 In this case, they are not independent elements but only areas of a single element that merge seamlessly into one another. The structure 130 is then only in that sense in the passage 120 arranged that the body 110 in a certain area instead of a single large-volume passage contains a plurality of independent and / or interconnected passages of small volumes. The passages can form a regular pattern and thereby form, for example, a sieve element or a lattice structure. However, the passages can also be completely or partially disordered or can be located within the structure 130 change in their shape.

For the one-piece production of bodies 110 and structure 130 are particularly well-known additive manufacturing processes such as 3D printing processes. Here are bodies 110 and structure 130 generated in the same additive building process. This allows the device 100 with particularly efficient filter structures, but still inexpensive to manufacture.

A particularly effective protection against the ingress of material to be degassed into the degassing device 100 can be achieved if the structure 130 in one of a surface of the body 110 adjacent area of the passage 120 is arranged. Then an edge of the structure runs 130 in the area of the inlet of the passage 120 flush or almost flush with the side of the body facing the material to be degassed 110 . The material to be degassed cannot therefore enter the passage 120 penetrate and not even on the edges of the opening of the passage 120 set. Such a configuration is exemplified in 2 shown.

The 2 shows in an exemplary and schematic manner part of an extrusion device 200 , in which an extrusion mass shown schematically as an arrow 210 is conveyed in the direction of the arrow in order to finally produce a plastic extrudate from it. In such extrusion devices known per se 200 are especially in the area of plasticizing cylinders in which the extrusion mass 210 Prepared for extrusion, degassing inserts are used to put in the extrusion mass 210 discharge contained gases. As the extrusion mass 210 If this is typically heated to temperatures between 150 ° C. and 200 ° C., all components that come into contact with the extrusion compound should be heat-resistant at least up to these temperatures.

In the 2 is a correspondingly shaped device as a degassing insert 100 for discharging gases shown as they are with reference to the 1A and 1B was described above. The degassing insert has a body shaped in the form of a flange or connecting piece 110 through which a cylindrical passage 120 runs in communicating connection with the extrusion mass conveyed, for example in the plasticizing cylinder 210 stands.

The extrusion mass 210 can here against the inlet opening of the passage 120 be pressed. This allows the extrusion mass 210 in the passage 120 and clog it. This can happen especially when part of the extrusion mass 210 is abraded at the edges of the inlet opening, for example because the outer edges of the extrusion compound 210 conveying screw run flush with the edge of the plasticizing cylinder.

To prevent this is in the device 100 the structure 130 so in the passage 120 is arranged so that its underside is flush or almost flush with the surface of the body 110 is that of the extrusion mass 210 is facing. The bottom of the structure 130 is therefore in an area of the passage adjacent to this surface of the body 120 arranged, for example at a distance of 0 mm, 1 mm, 5 mm, 10 mm or 20 mm from this surface. The top of the structure 130 , from which the gas flows, can be arranged at any point within the passage, as long as the mechanical stability of the structure 130 is not affected. The total height of the structure 130 can be, for example, 0.5 cm, 1 cm, 5 cm or 10 cm. The structure 130 can also do the entire pass 120 to complete.

By the location of the structure 130 directly at the entrance of the passage 120 can effectively prevent the extrusion mass 210 in the passage 120 got. As the extrusion mass 210 is sufficiently tough, there is also no sticking or clogging of the structure 130 . In addition, if the outer edges of a screw run flush with the edge of the plasticizing cylinder, they can form the extrusion compound 210 in a self-cleaning manner from the bottom of the structure 130 remove and thereby clog the structure 130 prevent.

By providing the structure 130 So becomes a degassing device 100 or a degassing insert is provided which can prevent clogging from occurring.

In addition, the degassing device 100 in a simple way for cleaning, maintenance or replacement from the extrusion device 200 can be removed. For example, if the structure is damaged, the device 100 be replaced. To remove the device 100 To facilitate this, this can be done with the closure of one in the 2 Entgasungsdoms not shown be connected to the above the device 100 is arranged and into which the gas is discharged. When the degassing dome is opened due to maintenance work, the device is automatically removed and can be checked for damage and, if necessary, replaced.

The device 100 thus not only allows a reliable separation of gas and the material to be degassed but can also be serviced in a simple manner.

List of reference symbols

100

Device for discharging gases

110

body

120

Passage

130

structure

200

Extrusion device

210

Extrusion compound

Claims (15)

Apparatus (100) for evacuating gases, comprising a body (110) having a passage (120) for evacuating gases; in which at least a part of the passage (120) is filled with a structure (130) which allows the passage of gases and prevents the passage of solids; and the structure (130) is fixed to the body (110). Device (100) after Claim 1 , wherein the structure (130) is inextricably linked to the body (110). Device (100) according to one of the preceding claims, wherein the structure (130) is made of the same material as the body (110) and is formed in one piece with the body (110); and the structure (130) preferably has a screen element connected in one piece to the body. Device (100) according to one of the preceding claims, wherein the structure (130) is arranged in a region of the passage (120) adjacent to a surface of the body (110). Device (100) according to one of the preceding claims, wherein the body (110) and the structure (130) were manufactured additively together. Device (100) according to one of the preceding claims, wherein the device (100) is a degassing insert. Device (100) according to one of the preceding claims, wherein the body (110) and the structure (130) are made of material which is heat-resistant, preferably up to a temperature between 150 ° C and 200 ° C. An extrusion device (200) for producing an extrudate from an extrusion mass (210), comprising means for conveying the extrusion mass (210); and the apparatus (100) according to any preceding claim; in which the device (100) is arranged in the extrusion device (200) in such a way that gases can be removed from the extrusion mass (210) via the passage (120) of the device (100). Extrusion device (200) after Claim 8 , further comprising a degassing dome into which the device (100) discharges the gases; wherein a closure of the degassing dome is connected to the device (100) in such a way that the device (100) can be removed from the extrusion device (200) at the closure. Method for manufacturing a device (100) according to one of the Claims 1 to 7th , comprising producing the body (110) and the structure (130) together by means of additive manufacturing. A method for producing a device (100) comprising the steps of: - creating a data set which the device (100) according to one of the Claims 1 to 7th maps; Storing the data set on a storage device or a server; and - inputting the data record into a processing device or a computer which controls a device for additive manufacturing in such a way that it manufactures the device (100) depicted in the data record. System for additive manufacturing of a device (100), comprising: - data set generating device for generating a data set which the device (100) according to one of the Claims 1 to 7th maps; - Storage device for storing the data set; - Processing device for receiving the data record and for controlling a device for additive manufacturing in such a way that it produces the device (100) shown in the data record. Computer program, comprising data sets which, when the data sets are read in by a processing device or a computer, causes them to control a device for additive manufacturing in such a way that the device for additive manufacturing has a device (100) with the features according to one of the Claims 1 to 7th manufactures. Computer-readable data carrier on which the computer program is based Claim 13 is stored. Data set, which a device (100) with the features according to one of the Claims 1 to 7th maps.

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