EP4015092A1 - Method and device for stripping a material residues from a dosing nozzle - Google Patents

Abstract

The invention relates to a method for scraping off a material residue (2) from a metering nozzle (3), the metering nozzle (3) with the material residue (2) being guided past a stripping element (10), so that the material residue (2) with the stripping element ( 10) comes into contact and is scraped off by the dosing nozzle (3), characterized in that the scraping element (10) performs a closed revolving movement, as a result of which a segment (16, 17) of the scraping element (10) initially reaches a scraping position, in which the residual material (2) is stripped from the dosing nozzle (3) and at least part of the residual material remains adhering to the segment (16, 17), is then guided with the residual material (2) adhering thereto to a separation position in which a separating unit (30), the material residue (2) is separated from the segment (16, 17) of the stripping element, and is guided again to the stripping position for receiving a further material residue (2). The invention also relates to a device (1) for stripping off the residual material (1).

Description

The invention relates to a method and a device for scraping off a material residue from a metering nozzle.

Sealing or adhesive materials are often applied industrially using a dispensing nozzle. At the end of the dosing, depending on the rheology of the material, a residue of material in the form of a thread adheres to the dosing nozzle. This thread can lead to soiling of the substrate/component if it falls off unintentionally or is laid down in an uncontrolled manner at the beginning of the next dispensing. This is very undesirable, particularly in the case of visible components or components from the electronics industry.

It is known from the prior art, after dosing has taken place, for example after applying a bead of adhesive, to guide the dosing nozzle by a robot movement just above a stripping element in the form of a tensioned wire transversely to the wire. The residue of material hanging down from the dispensing nozzle comes into contact with the wire and gets caught on it, so that the residue of material is wiped off the dispensing nozzle. With each new wiping process, the dosing nozzle is guided over the wiping wire with a small lateral offset compared to the last wiping process. This prevents the dosing nozzle from colliding with residual material from the last stripping. After a certain period of time, the wire has to be laboriously cleaned or replaced with a new wire. Cleaning or replacing the wire leads to high set-up costs, especially if a residue of material is wiped off the dispensing nozzle after each dispensing process or each bead of adhesive.

From the DE 20 2005 005 613 U1 it is known to heat the wire to strip off the remainder of the material. This burns the residues of material adhering to the wire. This can, however, produce toxic and harmful gases. In addition, there is a risk of burns from the hot wire.

The invention is therefore based on the object of providing a method for stripping a residue of material from a metering nozzle, which method works reliably and safely and can be carried out inexpensively.

The object on which the invention is based is achieved with the combination of features according to claim 1 . Embodiments of the invention can be found in the subclaims to claim 1.

According to the invention, it is provided that the stripping element performs a closed revolving movement, as a result of which a segment of the stripping element firstly reaches a stripping position. In the scraping position, the residual material is scraped off the dosing nozzle and at least part of the residual material remains attached to the segment. Thereafter, the segment with the residue of material adhering to it is guided to a separation position in which the residue of material is separated from the segment of the stripping element by a separation unit. Finally, the segment freed from the residue of material is guided back to the stripping position and is ready to receive another residue of material.

The rotating stripping element can consist of a large number of segments which are arranged one behind the other as seen in the direction of rotation. The segments are successively guided to the stripping position and then to the separating position by the revolving movement. Due to the closed revolving movement and the separating unit, the effective length of the stripping element (sum of the free segments on which a residual material can be deposited) is infinitely large. The stripping element can be used continuously for long periods of time. Downtimes caused by cleaning or replacing the scraper element can be avoided or at least significantly reduced.

A sealing or adhesive material can be dispensed with the dispensing nozzle. When dispensing, the sealing or adhesive material is free-flowing and has not yet hardened. As a rule, the residue of material adhering to the dosing nozzle, which is deposited on the segment by the wiping process, is also not yet in the hardened state. Depending on the rotational speed at which the stripping element rotates, the segment needs a certain amount of time from the stripping position to the separating position, in which the initially not yet hardened residue of material can at least partially harden. The remainder of the material preferably reaches the separation position in a hardened state or at least with a fully hardened surface skin. The separation of the remainder of material from the segment is preferably carried out mechanically, i.e. the remainder of material is separated from the segment by a mechanical force acting on it (e.g. cut, sheared or scraped off).

In one embodiment, the period of time for a circular movement of the segment from the stripping position to the separating position is greater than the tack-free time or greater than twice the tack-free time of the residual material. The tack-free time is to be understood here as the time that elapses from the point at which the residual material is applied to the segment to the point at which the surface skin of the residual material has hardened through. As far as adhesive material is concerned, which is metered out and thus also forms the material residue, the material residue is no longer sticky when the surface skin has hardened and can be mechanically separated from the segment without the risk that the separation unit will become damaged over time becomes a sticky mass and then no longer works reliably.

When determining an advantageous rotation time for a complete rotation of the scraping element, different parameters can be taken into account, such as the size and extent of the scraping element, the number of material residues to be scraped off per unit of time and the material properties of the material residue. The cycle time can be in a range from 10 minutes to 24 hours, for example.

The orbital movement can be a rotational movement about an axis of rotation. The stripping element is preferably designed essentially as a rotationally symmetrical body which is noted about the axis of rotation. A complete rotation of the stripping element is achieved when the stripping element has rotated through 360°. The rotationally symmetrical body can be divided into several (rotary) segments, each with the same angle of rotation. For example, a cylinder can be divided into 72 segments of equal size, each of which covers an angle of rotation of 5° when viewed in the direction of rotation.

Alternatively, the stripping element can have a closed but flexible circumference. An example of this is a closed wire loop that is stretched over two rollers that are spaced apart from one another.

In one embodiment, the orbital motion is clocked. This means that the stripping element stands still for a certain time and is moved intermittently in the direction of rotation. If, for example, the revolving movement is a rotary movement, the downtime can be 20 to 120 seconds, after which the stripping element is rotated further by a few degrees of rotation angle (1, for example, 10°). Alternatively, it can also be a continuous circulation movement.

The revolving stripping element can be driven by a swivel drive. If a compressed air network is available, a pneumatically driven swivel drive is a cost-effective and easy-to-control drive for the scraper element. The swivel drive provides a limited rotary or swivel movement in a first direction of rotation, which is followed by a rotary movement in an opposite, second direction of rotation.

In one embodiment, the swivel drive is coupled to the revolving stripping element via a freewheel. The rotary drive drives the stripping element in cycles in the direction of the first direction of rotation, the stripping element being decoupled from the rotary drive and not moving as a result of the freewheel during the rotary movement of the rotary drive in the opposite second direction of rotation. A suitable transmission gear can be used to move the stripping element by a few millimeters (e.g. 1 to 8 mm) or by a few degrees of rotation (e.g. 1 to 10°) per rotation of the rotary drive in the first direction of rotation. If, for example, the stripping element is rotated by 4° per rotary movement of the rotary drive in the first direction of rotation, 90 rotary or Pivoting movements in the first direction of rotation in order to allow the stripping element to rotate completely once. Between the 90 rotary movements in the first direction of rotation, a corresponding number of rotary movements of the pivoting drive in the second direction of rotation take place, but the stripping element then comes to a standstill due to the freewheel.

As an alternative to the swivel drive, an electric motor (stepping motor or servo motor) can also be used.

The stripping element can be coated with an anti-stick material, at least partially, in order to make it easier to separate the remaining material from the segment or from the stripping element. An example of a preferred anti-stick material is PTFE.

Alternatively, the scraping element can be made of a non-stick material such as PTFE. If the stripping element is a one-piece component, it can consist entirely of the non-stick material.

The separating unit can have at least one first scraping blade, which bears against the rotating scraping element, so that the residual material applied to the segment is pressed against the scraping blade by the rotating movement of the scraping element. The scraping blade separates the remaining material from the segment or from the scraping element. The scraping blade is preferably stationary, so that the relative movement between the segment/material residue and the scraping blade can only be attributed to the rotary movement of the scraping element. It is also conceivable that the scraping blade additionally performs its own separating or scraping movement.

The separated material residue can be fed into a collection container. In one embodiment, the separated material residue falls into the collection container due to the force of gravity. The size of the collection container can be dimensioned in such a way that it only needs to be emptied at very long intervals. Another option is to place the separated material residues on a conveyor belt, which transports the material residues away continuously or in cycles.

If the remainder of the material essentially remains in the form of an elongated thread on the segment, the thread can be successively guided to the scraping blade in the cutting position. This means that the thread is successively separated from the segment along its length by means of the scraping blade. High force peaks during the cutting process can thus be avoided. This reduces the maximum torque required to drive the revolving stripping element and the maximum forces that act on the separating unit and on the stripping element during cutting.

After the stripping position and before the separating position, the remainder of the material can be subjected to water, steam and/or heat. If the material dispensed through the dosing nozzle is a one-component adhesive that hardens more quickly with water vapor or water, the reaction of the remaining material on the segment with water vapor/humidity can be accelerated by spraying with water mist. If it is a two-component adhesive whose components react more quickly at higher temperatures, the wiper element can be heated. At an increased temperature level, the two-component adhesive, or at least its surface skin, hardens faster, which reduces the risk of the separation unit becoming clogged with a sticky mass over time. The supply of heat can thus reduce the time required for (partial) curing of the residual material between the stripping position and the separating position.

A further object of the invention, the provision of a simply constructed and efficiently working device for scraping off the material residue from the dosing nozzle, is achieved with the combination of features according to claim 11. Exemplary embodiments of this can be found in the dependent claims of claim 11 .

The device according to the invention has a scraper disk which is mounted rotatably about an axis of rotation and serves to receive the residual material scraped off by the dosing nozzle, and a separating unit with at least one preferably fixed scraper blade which rests against the scraper disk, with rotation of the scraper disk about the axis of rotation of the recorded residual material can be separated by the scraping blade. The contact between the scraper blade and the scraper disc can be subject to play. Alternatively, the scraping blade can also press on the scraper disk with a certain pretension in order to guarantee that the remaining material is separated from the scraper disk as completely as possible. The preload between the scraping blade and the scraper disk increases the friction that opposes the rotary movement of the scraper disk and has to be overcome by the drive of the scraper disk, but the scraper disk can be guided more precisely with a certain amount of friction, especially in the case of a clocked rotary movement. Without any frictional resistance, in an exemplary embodiment in which a freewheel is provided between the scraper disk and the pivoting operation, the scraper disk could move beyond the desired target position due to inertia at a given angular momentum by the drive. As an alternative or in addition to the prestressing between the scraping blade and the scraper disk, the device according to the invention can have a resistance and grinding element which opposes a certain (frictional) resistance to the rotating movement of the scraper disk.

The separating unit can have a U-shaped scraping blade with two blade legs and a blade base, with the two blade legs on a front and a rear base surface of the scraper disk and the blade base on a lateral surface of the scraper disk issue. The U-shaped scraper blade makes it possible to remove material residues adhering to practically the entire surface of the scraper disc.

In one embodiment, the blade legs extend from the blade base generally radially towards the axis of rotation of the stripper disk. A main extent of the blade limbs and a radial connecting line between the axis of rotation and the blade base can enclose an angle which can assume values from 0 to 30°. The free end of the blade shank is therefore not directed directly at the axis of rotation of the scraper disk, but has a certain offset to the axis of rotation. This angle or this offset allows a material residue in the form of a thread, which extends radially on one of the base surfaces of the scraper disk, to be successively separated from the base surface of the scraper disk by the blade shanks.

The blade shanks can be of the same length or of different lengths. For example, the blade leg, which is arranged on the base surface of the scraper disk that faces the drive of the scraper disk, can be made somewhat shorter.

In another exemplary embodiment, the separating unit has an L-shaped scraping blade with two blade limbs, one blade limb resting on the front base surface and the other blade limb on the outer surface of the scraper disk. As in the case of the U-shaped scraping blade, in the case of the L-shaped scraping blade the blade leg which rests against the front base surface can have a certain offset with respect to the axis of rotation. An angle between this blade leg and the radial connecting line between the axis of rotation and the corner point of the L-shaped scraping blade can assume values between 0 and 30°. The blade limb resting on the base surface is preferably longer than the blade limb resting on the lateral surface.

Figur 1

eine Vorrichtung zum Abstreifen eines Materialrests in einem ersten Ausführungsbeispiel;

Figur 2

das Ausführungsbeispiel der Figur 1 von der Seite;

Figur 3

ein zweites Ausführungsbeispiel der Erfindung;

Figur 4

das Ausführungsbeispiel der Figur 3 von der Seite; und

Figur 5

eine Abtrenneinheit entlang der Linie V-V in Figur 3.

The invention is explained in more detail on the basis of the exemplary embodiments illustrated in the drawing. Show it:

figure 1

a device for scraping off a residue of material in a first embodiment;

figure 2

the embodiment of the figure 1 of the page;

figure 3

a second embodiment of the invention;

figure 4

the embodiment of the figure 3 of the page; and

figure 5

a separation unit along the line VV in figure 3 .

the Figures 1 and 2 show a device 1 for wiping off a material residue 2 from a metering nozzle 3. The device 1 comprises a wiping element 10 and a separating unit 30. The wiping element 10 is designed in the form of a circular wiping disk 11, which is rotatably mounted about an axis of rotation 12.

The scraper disc 11 has a front base 13 and a rear base 14, the rear base 14 only in figure 2 can be seen. A lateral surface 15 extends between the front base surface 13 and the rear base surface 14. The diameter of the scraper disk can be in a range from 50 to 200 mm, preferably between 100 and 150 mm. A thickness of the scraper disc 11 can be in a range of 2 to 25 mm, preferably 3 to 7 mm. The front base surface 13, the rear base surface 14 and/or the lateral surface 15 can be coated with an anti-stick material. Alternatively, the wiper disk 11 can be made entirely of the non-stick material.

Above the scraper disc 11 is the dosing nozzle 3, through which a flowable material such as liquid adhesive can be applied to a substrate or a component (not shown). After a bead of adhesive has been applied to the component, a residue of material in the form of a thread 2a to 2g can remain on the metering nozzle 3, which must be removed from the metering nozzle 3 before another bead of adhesive is applied. For this purpose, the dosing nozzle 3 is moved past the scraper disc 11 . The arrow 4 in figure 1 and the arrow 5 in figure 2 indicate the direction in which the dosing nozzle is guided past the scraper disc 11 above it. In the representation of figure 2 the dosing nozzle 3 is guided above the scraper disc 11 along the arrow 5 from left to right. In the representation of figure 1 movement of the metering nozzle 3 runs perpendicular to the plane of the drawing and into it. A material residue 2 hanging on the metering nozzle 3 is thereby stripped off by the movement of the metering nozzle 3 and comes to rest against the front base surface 13. The Figures 1 and 2 show a state in which the thread designated 2g has just been stripped from the dosing nozzle 3. From the figure 2 it becomes clear that the metering nozzle 3 has just passed a front edge 20 between the front base surface 13 and the lateral surface 15 .

The scraper disc 11 can be divided into a large number of segments, of which figure 1 only two of these segments are indicated by dash-dotted lines. A first segment is indicated at 16 and is in a stripping position. A second segment is indicated at 17 and is in a severing position.

The segment 16 in the stripping position serves to strip off the material residue to be separated from the metering nozzle 3 from the metering nozzle when the metering nozzle 3 is passed directly above the segment 16 and to pick it up accordingly. After the stripping process, the stripping disc 11 is rotated further in the direction of arrow 18 until another, not with a Material residue occupied segment reaches the stripping position (on a clock face the stripping position is at 12 o'clock).

The second segment 17 is in the separating position, in which the thread 2a located there is scraped off the front base surface 13 by the separating unit 30 . In figure 1 It is indicated that an inner part of the thread 2a viewed in the radial direction has already been severed from the base 13 and hangs loosely downwards. If the scraper disk 11 is rotated further in direction 18, a middle part and an outer part of the thread 2a also hit the separating unit 30, so that finally the thread 2a is completely separated from the base surface 13 of the scraper disk 11 and is pushed in the direction of the Arrow 19 falls down. Below the segment 17 in the severing position is a collecting container, not shown, into which the severed thread 2a falls.

figure 1 shows further threads 2b to 2f, which have already been deposited on the stripping disk 11 by previous stripping processes. Between the individual stripping processes, the stripping disk 11 was rotated further in each case by a specific angle of rotation. Seen in the circumferential direction, the distance between adjacent threads on the scraper disc 11 can be significantly smaller than in figure 1 shown. The threads 2a to 2g shown are therefore only examples of a large number of threads which are applied to the front base surface 13 by the metering nozzle 3 being repeatedly passed above the scraper disk 11 and the further rotation of the scraper disk 11 in the meantime. For example, the distance between two adjacent threads viewed in the circumferential direction can be only 2 to 5°. Correspondingly, the segments of the scraper disk 11 can also each only extend over this circumferential area of 2 to 5°.

Seen in the direction of rotation 18 behind the separating unit 30 there are no longer any threads (see area between 9:00 and 12:00). Thus, starting from the in figure 1 bring the state shown by a further rotation of the scraper disc 11 free segments in the stripping position to pick up more material residues 2 there. Due to the separating unit 30, the scraper disc 11 can perform one full rotation after the other, which makes continuous use of the device 1 possible. Since the stripping disc 30 is automatically freed from the threads 2a to 2g during normal operation of the device 1, set-up times for cleaning the device 1 or for replacing individual components of the device 1 can be significantly reduced.

In the exemplary embodiment shown here, the separating position is offset by approximately 270° in relation to the stripping position. This means that the stripping disc 11 would have to be rotated by a total of 270° in correspondingly small steps or also continuously so that the segment 16 would have to reach the separating position starting from the stripping position.

In figure 2 For the sake of clarity, only the thread 2g that has just been stripped from the dosing nozzle 3 and the bottom thread 2c are shown, which has been stripped some time before the thread 2g. The scraper disk 11 is driven in rotation by a drive unit 50 which comprises a motor in the form of a pneumatic swivel drive 51 , a freewheel 52 and a drive shaft 53 . The pneumatic swivel drive 51 performs a first rotational movement in the direction of the direction of rotation 18 and a second rotational movement opposite to the first rotational movement. The freewheel 52 is designed in such a way that the second rotational movement of the swivel drive 51 is not passed on to the drive shaft 53 . The drive shaft 53 and the scraper disk 11 connected to it in a rotationally fixed manner are therefore stationary when the pivoting drive 51 moves in the opposite direction to the direction of rotation 18 . A transmission, not shown here, which can be provided between the swivel drive 51 and drive shaft 53, preferably has a gear ratio such that the ratio of the angle of rotation of the swivel drive 51 to the angle of rotation of the scraper disk 11 is greater than 1.

In figure 2 It can also be seen that the separating unit 30 rests not only on the front base 13 but also on the rear base 14 . As a result, material residues or parts of material residues that get stuck on the rear base surface 14 during the stripping process can also be separated by the separating unit 30 .

In order to change the stripping process in such a way that the material residues 2 do not reach the rear base area 14 at all, if possible, the figure 2 horizontal axis of rotation 12 are slightly inclined to the horizontal, so that the front base 13 is pivoted slightly upwards. The rear base 14 is rotated slightly downwards. This inclined axis of rotation also causes a rear edge 21 to be offset slightly downwards relative to the front edge 20, as a result of which the distance between the rear edge and the metering nozzle 3 is increased.

the Figures 3 and 4 show another embodiment of the device 1 according to the invention, with components and features belonging to the components and features of Figures 1 and 2 are similar or identical are provided with the same reference numerals. When describing the Figures 3 and 4 are essentially only the differences from the first embodiment of the Figures 1 and 2 described. With regard to the similarities, reference is made to the previous description of the figures.

The device 1 according to the embodiment of Figures 3 and 4 comprises a dip tank 70 into which a lower part of the scraper disc 11 protrudes. The dip tank 70 is filled with a liquid 71, preferably with water. Each thread 2a to 2g, which has been stripped from the dosing nozzle 3 and thereby deposited on the front base surface 13, thus passes through the dip tank 70 filled with the liquid 71.

If the material that is metered out through the metering nozzle 3 is a one-component adhesive that hardens as a result of atmospheric moisture or water (vapor), then this is the case the baptismal font 70 accelerates the hardening of the threads 2a to 2g on the scraper disk 11. This can prevent the separating unit 30 becoming clogged with sticky material over a long period of time and no longer reliable due to insufficiently hardened threads which still have a sticky surface is working.

When using a two-component adhesive, the liquid 71 in the dip tank can have an elevated temperature in order to apply heat to the threads. The heat accelerates the reaction between the two components of the adhesive. Here, too, the dip tank serves to accelerate the hardening of the threads on the way from the stripping position to the separating position. As an alternative or in addition, the scraper disk 11 can also be heated directly.

Irrespective of the influence on the hardening, the immersion tank 70 can also be used to wet the stripping disk 11 with the liquid 71 in order to reduce the adhesion of the individual threads on the stripping disk 11 . This does not primarily apply to the threads that have already been deposited and run through the dip tank, but to future threads that, during the continuous operation of the device 1 after the stripping disk 11 has passed through the dip tank 70, reach the then wetted surface of the stripping disk 11.

Compared to the embodiment of Figures 1 and 2 are in the embodiment Figures 3 and 4 the location and orientation of the separation unit 30 changed slightly. figure 5 is a section along line VV in figure 4 . The separating unit 30 has a U-shaped scraping blade 31 with a front blade limb 32 , with a rear blade limb 33 and with a blade base 34 . The front bell leg 33 rests on the front base surface 13 of the scraper disc 11 and serves to scrape off the threads 2a to 2g adhering to the front base surface 13. The rear base surface 14 is freed from any adhering material residues by the rear blade leg 33 . The blade base 34 is used to clean the lateral surface 15.

The front blade limb 32 and the rear blade limb 33 can be of the same length or, as shown here, also have different lengths. In the exemplary embodiment illustrated here, the front blade limb is longer than the rear blade limb 32 and protrudes slightly beyond the center point or the axis of rotation 12 of the scraper disk 11 . This ensures that the entire front base 13 is freed from the threads 2a to 2g.

In figure 3 It can be seen that at least the front blade limb 32 and preferably also the rear blade limb 33 encloses an angle 36, which can be 2 to 20°, to a radial connecting line 35 which connects the blade base 34 to the axis of rotation 12. This ensures that a thread 2a to 2g, which extends essentially in the radial direction on the scraper disk 11, successively hits the front blade limb 32. Thereby unwanted force peaks can be avoided when cutting off or scraping off the threads 2a to 2g.

A free end 37 of the rear blade leg 33 can be used to connect an end 54 of the drive shaft 53 facing the scraper disc 11 (see figure 4 ) of any residual materials.

Reference List

1

scraper device

2

Leftover material (thread 2a to 2g)

3

dosing nozzle

4

Arrow

5

Arrow

10

scraper element

11

scraper disc

12

axis of rotation

13

Floor space

14

Floor space

16

lateral surface

16

first segment

17

second segment

18

arrow/direction of rotation

19

Arrow

20

front edge

21

back edge

30

divider

31

scraping blade

32

blade shank

33

blade shank

34

blade base

35

radial connecting line

36

angle

37

free end

50

drive unit

51

pneumatic swivel drive

52

freewheel

53

drive shaft

54

End

70

plunge pool

71

liquid

Claims (15)

Method for scraping off a material residue (2) from a metering nozzle (3), the metering nozzle (3) with the material residue (2) being guided past a stripping element (10) so that the material residue (2) comes into contact with the stripping element (10). and is wiped off by the dosing nozzle (3), characterized in that the wiping element (10) performs a closed revolving movement, through which a segment (16, 17) of the wiping element (10) - first reaches a stripping position in which the residual material (2) is stripped off the metering nozzle (3) and at least part of the residual material remains attached to the segment (16, 17), - is then guided with the material residue (2) adhering to it to a separating position in which the material residue (2) is separated from the segment (16, 17) of the stripping element by a separating unit (30), and - Is led back to the stripping position for receiving another material remainder (2). Method according to Claim 1, characterized in that a sealing or adhesive material is metered out with the metering nozzle (3). Method according to Claim 2, characterized in that a period of time for a circular movement of the segment (16, 17) from the stripping position to the separating position is greater than the tack-free time of the sealing or adhesive material. Method according to Claim 1 or 2, characterized in that the circulation movement is clocked. Method according to one of Claims 1 to 4, characterized in that the revolving movement is a rotary movement about an axis of rotation (12). Method according to one of Claims 1 to 4, characterized in that the revolving stripping element (10) is driven by a pneumatic swivel drive (51). Method according to one of Claims 1 to 6, characterized in that the stripping element (10) is coated with an anti-adhesive material over at least part of its surface or is made from an anti-adhesive material. The method according to any one of claims 1 to 6, characterized in that the separating device (30) has at least one scraping blade (31) on which rotating stripping element (10), so that the material residue (2) applied to the segment (16, 17) is pressed against the scraping blade (31) by the rotating movement of the stripping element (10). Method according to Claim 8, characterized in that the material remainder (2) is deposited essentially in the form of an elongated thread (2a to 2g) on the segment (16, 17), the thread (2a to 2g) successively advancing in the separating position the scraping blade (31) is guided. Method according to Claim 10, characterized in that after the stripping position and before the separating position the material remainder (2) is subjected to water, steam and/or heat. Device (1) for scraping off a material residue (2) from a dosing nozzle (3), comprising - a scraper disc (11) which is mounted rotatably about an axis of rotation (12) and serves to receive the material residue (2) scraped off the metering nozzle (3), and - a separating unit (30) with at least one scraping blade (31) which bears against the scraper disk, wherein when the scraper disk (11) rotates, the material residue picked up can be separated by the scraping blade (31). Device according to Claim 11, characterized in that the scraping blade (31) is U-shaped and has two blade legs (32, 33) and a blade base (34), the two blade legs (32, 33) being attached to a front base surface (13) or on a rear base surface (14) of the scraper disc (11) and the blade base (34) on a lateral surface (15) of the scraper disc (11). Device according to Claim 12, characterized in that the blade legs (32, 33) extend radially from the blade base (34) in the direction of the axis of rotation (12) of the scraper disc (11). Device according to Claim 13, characterized in that a main extension of the blade legs (32, 33) and a radial connecting line (35) between the axis of rotation (12) and blade base (34) enclose an angle (36). Device according to Claim 11, characterized in that the scraping blade (31) is L-shaped and has two blade limbs, one blade limb resting on a front base surface (13) and the other blade limb on a lateral surface (15) of the scraper disc (11). .

Images