DE102019002053A1 - Device for discharging gases with a sieve device - Google Patents

Abstract

A device (100) for evacuating gases comprises a body (110) with a passage (120) for evacuating gases and a sieve element (130) arranged in the passage (120) through which gases passing through the passage must enter Permits passage of gases and prevents the passage of solids. The sieve element (130) can be removed from the passage (120) in the flow direction of the discharged gas.

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 For example, in extrusion devices, gases are withdrawn from the plastically deformable extrusion compound while it is being conveyed through the extrusion device.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 can for example have a body with a passage for evacuating gases and a sieve element arranged in the passage through which gases passing through the passage must pass, which allows passage of gases and which prevents passage of solids. The screen element can be removed from the passage in the direction of flow of the discharged gas.

As with conventional degassing devices, the passage serves to discharge gases. However, there is also the sieve element, which is impermeable to solids. In this way it is ensured that gas discharged through the device is separated by means of the sieve element from the material from which the gas is discharged. The sieve element can have any shape that allows the passage of solids to be prevented in the entire cross section of the passage and at the same time allows the sieve element to be removed from the passage or from the body of the degassing device. This allows the screen element to be removed without removing the entire degassing device in order to maintain, clean or replace it. This provides a degassing device which is reliably protected against the ingress of solids to be degassed and which can be easily serviced.

The sieve element can be connected in the removal direction to a removal device which protrudes from the passage. This makes it possible to pull the screen element out of the passage without additional tools. This particularly simplifies maintenance.

The sieve element can have a sieve basket with a plurality of small tubes which extend against the direction of flow of the discharged gas. This represents a structurally simple construction of the sieve element, since the penetration of solids is prevented solely by tubes running in the penetration direction without intermediate braces. In addition, the course of the tubes facilitates the removal of the sieve element, since elements of the sieve element running across the wall of the passage cannot jam. In addition, the bundle of parallel tubes is very stable against shear forces, so the sieve element is very stable.

The sieve element can end in a region of the passage adjacent to a surface of the body. The screen element thus ends near the edge of the device, e.g. 0 mm, 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. In particular, a slow build-up of material due to abrasion can also be prevented if the sieve element is arranged in the passage such that its underside 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 body described above and / or the sieve element described above can be manufactured additively, for example by means of a 3D printing process known per se. This makes it possible to manufacture the sieve element with particularly thin and / or long elements, such as the small tubes described above, which otherwise could not be manufactured. The structure of the sieve element is limited solely by the need to allow gas, but not solids, to pass through the sieve element and to enable, preferably facilitate, removal of the sieve element from the passage.

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 / or the screen element can be made of material that is heat-resistant, preferably up to a temperature between 150.degree. C. and 200.degree. 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 further comprise a degassing dome into which the device discharges the gases, a closure of the degassing dome being connected to the sieve element in such a way that the sieve element can be removed from the extrusion device at the closure. This makes it possible to remove the screen element in a simple manner from the extrusion device in order to maintain, clean or replace it. The sieve element is preferably connected to the closure of the degassing dome via the removal device described above.

A method for manufacturing a degassing device as described above comprises manufacturing the body and / or the sieve element 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, the body as described above and / or the sieve element 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 produces the degassing device, body and / or sieve element 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, the body as described above and / or the sieve element 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 for additive manufacturing in such a way that it produces the degassing device, the body and / or the sieve element depicted 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, the body as described above and / or the sieve element as described above 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 body as described above and / or the sieve element 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 is to be described in detail below with reference to the figures become. 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 shape of the body 110 for example, the shape of the device 100 define. 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 sieve element 130 that is permeable to gases but not to solids. The sieve element 130 can, for example, have a network or lattice structure whose mesh size does not allow the penetration of solids to be degassed. Passages through the sieve element that are passable for the gas 130 such as the meshes of a network structure can be arranged regularly. However, the passages can also have an irregular distribution, such as in a sponge. The sieve element 130 can therefore be constructed in any shape that allows gas, but not solids, to pass through. The sieve element 130 So ensures that the passage 120 is not clogged by penetrating material to be degassed.

Here the sieve element 130 from the passage 120 can be removed from above. This ensures that the sieve element 130 can be easily serviced, cleaned or replaced. The reliability of the functionality of the degassing device 100 is thereby improved. The removal can be done with a additional tool, such as a hook or the like.

As in the 1A and 1B however, a removal device can also be shown 140 present the top of the passage 120 protrudes. The extraction device 140 is in the 1A and 1B Shown as a cylindrical nozzle, the top of a holder of the screen element 130 is attached. The socket can be grasped in a simple manner as it extends over the body 110 the device 100 stands out. The sieve element attached to it 130 can thus easily out of the passage 120 to be pulled. It goes without saying that the removal device 140 (or the nozzle) must be designed in such a way that the discharge of the gas through the device 100 is not hindered, for example by appropriate recesses in the material of the removal device 140 .

Although in the figures the removal device 140 is shown as a nozzle, it goes without saying that this can be any type of auxiliary that is suitable, the sieve element 130 in a simple way from the body 110 refer to. For example, it can be the removal device 140 also be one or more rods or a linkage or ropes that are connected to a holder of the screening device 130 are connected. This can also make it easier to discharge the gas.

The extraction device 140 can also serve to keep the screen element in a certain position in the passage 120 to keep. The removal device 140 like in the 1A by the dashed continuation of the removal device 140 indicated so by the body 110 extend away that it can be attached at its upper end to a stationary object, for example a machine part such as the degassing dome of an extrusion device. The sieve element 130 then depends on the fixed object held in the passage 120 . At the same time, the rigidity of the removal device 140 , for example, if this is designed as a rod or nozzle, the position of the screen element 130 Stabilize against material to be degassed pressing from below. The extraction device 140 then acts as a spring that the sieve element 140 drives back to its original position.

The sieve element 130 but can also without the removal device 140 stable in passage 120 be held and still out of the passage 120 be removable. For example, a screen element that is deformable to a certain extent 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 sieve element is due to the clamping 130 stabilized against the pressure of the material to be degassed. Nevertheless, the sieve element can 130 out of the passage again by applying the appropriate force, which is greater than the forces occurring during degassing 120 be released, for example by a hook introduced from the outside.

In this way a degassing device 100 which is easy to maintain and which will not clog or corrode due to ingress of a material to be degassed.

A particularly effective protection against the ingress of material to be degassed into the degassing device 100 can be achieved if the sieve element 130 in one of a surface of the body 110 adjacent area of the passage 120 lies. Then an underside of the sieve element 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 pressed become. 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, the device 100 a sieve element 130 with a strainer basket 135 whose lower edge is flush or almost flush with the surface of the body 110 is that of the extrusion mass 210 is facing. The sieve element 130 or the strainer basket 135 therefore lie in an area of the passage adjacent to this surface of the body 120 . A distance between the bottom of the strainer basket and the bottom of the device 100 can be, for example, 0mm, 1mm, 5mm, 10mm or 20mm.

The sieve element 130 This 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 screen element 130 or the strainer basket 135 . 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 sieve element 140 remove and thereby a clogging of the sieve element 140 prevent.

By providing the sieve element 130 So becomes a degassing device 100 or a degassing insert is provided which prevents clogging.

Like in the 2 shown has the sieve element 130 a strainer basket 135 consisting of a plurality of thin, curved tubes extending from one at the passage 120 adjacent part of the sieve element downwards, ie extend along the flow direction of the gas to be discharged. If these tubes are packed sufficiently close within the passage 120 this enables gas to pass through, but solids cannot penetrate. Due to the lack of cross bracing, such a strainer basket 135 can be easily removed from the passage.

In addition, such a tight packing of thin tubes as a whole is very stable against transverse forces acting on them, which are caused by the extrusion compound 210 on the sieve basket 135 can be exercised as long as the individual tubes are sufficiently flexible. With a sieve element 130 with a classic basket or cage shape, a would be in the area of the inlet opening of the passage 120 transverse grid held on its circumference by a cylindrical grid. Such a construction can be deformed or depressed relatively easily by shear forces. In contrast, more force is required to bend or kink a bundle of tightly packed parallel tubes.

That's why a strainer basket 135 like him in the 2 is shown, more resistant to the extrusion mass 210 exerted shear forces than an ordinary screen basket or cage. With a sieve element 130 according to the 2 equipped degassing devices 100 so have an improved service life.

The degassing device 100 of the 2 has as well as the device of 1A and 1 B a removal device 140 on. As described above, the sieve element 130 thereby in a simple manner for cleaning, maintenance or replacement from the extrusion device 200 can be removed.

To remove the sieve element 130 further to facilitate or to its position in the passage 120 can be defined by the sieve element 130 via the removal device 140 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 sieve element becomes 130 automatically removed and checked for damage and replaced if necessary. When the degassing dome is closed again, the sieve element becomes 130 automatically in the correct position in the passage 120 arranged.

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

Sieve element

135

Strainer basket

140

Extraction device

200

Extrusion device

210

Extrusion compound

Claims (15)

Apparatus (100) for evacuating gases, comprising a body (110) having a passage (120) for evacuating gases; and a screen element (130) disposed in the passage (120) through which gases passing through the passage must pass, which allows passage of gases and which prevents passage of solids; in which the sieve element (130) can be removed from the passage (120) in the direction of flow of the discharged gas. Device (100) after Claim 1 , the sieve element (130) being connected in the removal direction of the sieve element (130) to a removal device (140) which protrudes from the passage (120). Device (100) according to one of the preceding claims, wherein the sieve element (130) has a sieve basket with a plurality of small tubes which extend counter to the flow direction of the discharged gas. Device (100) according to one of the preceding claims, wherein the sieve element (130) ends 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 / or the sieve element (130) was manufactured additively. 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 / or the sieve element (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 compound (210), comprising Means for conveying the extrusion mass (210); and the device (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; a closure of the degassing dome being connected to the device (100) in such a way that the sieve element (130) at the closure can be removed from the extrusion device (200). Method for manufacturing a device (100) according to one of the Claims 1 to 7th , comprising producing the body (110) and / or the sieve element (130) by means of additive manufacturing. A method for producing a device (100) comprising the steps of: - creating a data set which the device (100), the body (110) and / or the sieve element (130) 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 produces the device (100), the body (110) and / or the sieve element (130) 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), the body (110) and / or the sieve element (130) 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), the body (110) and / or the sieve element (130) depicted 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), the body (110) and / or the sieve element (130) 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 record which a device (100), the body (110) and / or the sieve element (130) with the features according to one of the Claims 1 to 7th maps.

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