Nozzle arrangement and dispensing apparatus for a fluid

Abstract

 The invention relates to a nozzle arrangement (4) and/for an apparatus (1) for dispensing fluid, especially adhesive, with a first nozzle part (20), a second nozzle part (22), which can be attached to the first nozzle part (20), at least one channel (24) formed in the first nozzle part (20) and/or the second nozzle part (22), into which fluid can be introduced, and at least one outlet opening (30) for dispensing fluid, which can be brought into fluid connection with the at least one channel (24). According to the invention the first nozzle part and the second nozzle part are arranged to one another in a pivoting manner.

Description

[0001] The present invention relates to a nozzle arrangement for an apparatus for dispensing a fluid, especially an adhesive, with a first nozzle part, a second nozzle part, which can be attached to the first nozzle part, at least one channel formed in the first nozzle part and/or the second nozzle part, into which fluid can be introduced, and at least one outlet opening for dispensing fluid, which can be brought into fluid connection with the at least one channel.

[0002] The invention further relates to an apparatus for dispensing fluid, especially an adhesive, to a substrate, with a base body comprising a fluid feed channel which can be connected to a fluid source, a nozzle arrangement comprising a channel which can be connected to the feed channel, and an outlet opening for dispensing the fluid, wherein the nozzle arrangement comprises a first nozzle part and a second nozzle part, which can be attached to the first nozzle part, and a valve arrangement for selectively interrupting or releasing the fluid flow.

[0003] These nozzle arrangements and discharge apparatuses are for example used to apply adhesives or other fluids to packaging materials, furniture parts, films, sanitary products or the like. The nozzle arrangement can be formed as a so-called slot nozzle arrangement with an essentially slot-shaped outlet opening. Alternatively, it can comprise one or several circular or differently formed outlet openings to dispense and apply the fluid to a substrate in the form of purl seams or strips.

[0004] The nozzle arrangement is connected to the base body of the dispensing apparatus during operation, especially screwed together therewith. This connection is designed in such a manner that fluid adhesive can flow from an adhesive source, which can be formed as a melting device, into the feed channel of the base body and the at least one channel in the nozzle arrangement. The adhesive flows through the one channel of the nozzle arrangement and is dispensed through the at least one outlet opening and applied to the substrate. The application can be applied to the substrate with the contact method, where a part of the nozzle arrangement is in contact with the substrate, or without contact. The flow of the fluid within the dispensing apparatus and the nozzle arrangement and especially from the outlet opening can selectively be released or interrupted by means of the valve arrangement. Such a nozzle arrangement and dispensing apparatus is for example known from DE 20 2006 019 724 U1.

[0005] The nozzle arrangement flown through by the fluid, for example adhesive, has to be cleaned or serviced from time to time. At the end of a production phase, it is for example necessary to remove the adhesive present in the channels of the nozzle arrangement. Sealing elements as e.g. O-rings or sealing profiles have to be exchanged or processed within the scope of a service. The individual parts of the nozzle arrangement are extensively or completely disassembled with the known nozzle arrangements. Screw connections with which the nozzle parts are attached to one another, are loosened manually for this purpose. Possible pins for the positioning or fixing of the nozzle parts relative to one another also have to be removed for this. The parts of the nozzle arrangement are assembled again after a cleaning of the nozzle parts or other parts of the nozzle arrangement. The assembly and disassembly is relatively time-consuming, as all individual parts have to be loosened, screw connections have to be loosened, and the parts have to be disassembled and subsequently be assembled again. A relative high expenditure of time results thereby during cleaning or servicing.

[0006] It is the object of the present invention to provide a nozzle arrangement and an apparatus for dispensing fluid, which can be disassembled and assembled in a more simple manner. The invention solves this object with a nozzle arrangement according to claim 1 in that the first nozzle part and the second nozzle part are arranged relative to one another to one another in a pivotal manner. The invention likewise solves the object with an apparatus for dispensing fluid of the above-mentioned type with the characteristics of claim 10.

[0007] The effort during the disassembly and assembly of the nozzle arrangement can be reduced considerably by the pivotal arrangement of two nozzle parts relative to one another. One nozzle part can for example simply be pivoted away from the other part for cleaning or service purposes, without having to loosen the part completely from the other nozzle part. A connection of the nozzle parts remains thereby. The cleaning or service can take place after pivoting away, for example, adhesive can be removed from the channel or the several channels within the nozzle arrangement, or also outer surfaces of the nozzle arrangement, or seals such as O-rings or other sealing elements can be exchanged. The pivoted nozzle part can subsequently simply be pivoted back into a closed position. The disassembly and the assembly is thereby considerably faster, as no new positioning of one nozzle part relative to the other nozzle part would be necessary. The nozzle parts can be opened or closed by the pivotal arrangement. The cleaning and service times can be considerably reduced thereby.

[0008] A preferred embodiment is characterised in that the nozzle arrangement is formed as a slot nozzle arrangement and comprises at least one essentially slot-shaped outlet opening, and that the outlet opening is limited at least partially by a section of the first nozzle part and a section of the second nozzle part. The advantages according to the invention come into their own especially with slot nozzle arrangements having comparatively large dimensions.

[0009] It is particularly preferred that the first nozzle part and the second nozzle part are connected to one another by means of a hinge joint. A hinge joint is reliable and simple, so that the ability to swing open results in a simple manner.

[0010] It can be advantageous for the handling of the pivotable nozzle arrangement, that the ability to pivot is limited by at least one stop element. Other apparatus parts are protected by such a stop element and the nozzle part which is pivoted away can be fixed in a simple manner, so that does not interfere with cleaning operatins.

[0011] It is suggested according to an alternative embodiment that the first nozzle part and the second nozzle part can be clamped to one another by means of at least one bolt. After the cleaning or servicing, the two nozzle parts can be tightly pressed to one another by means of one or preferably several bolts, so that inner flow channels are sealed. These bolts can simultaneously be loosened quickly with commercial tools.

[0012] According to a further embodiment, it is suggested that the at least one bolt is arranged at least partially within a recess which is formed in the first nozzle part and/or the second nozzle part. In this case, the bolt can be loosened and then be pivoted slightly within the slot, so that the nozzle part which can be pivoted away can be moved freely without the bolts being in the way. The bolts can thereby themselves be arranged in a pivoting manner at the nozzle arrangement or at another part, so that they do not have to be loosened completely. Advantageously, slots are formed in the nozzle parts, within which the bolts can be pivoted.

[0013] A manifold is preferably formed in the first nozzle part and/or the second nozzle part, which manifold can be brought into fluid connection with an essentailly slot-shaped outlet channel, which is limited by a section of the first nozzle part and a section of the second nozzle part and which leads into the essentially slot-shaped outlet opening.

[0014] A preferred embodiment of the dispensing apparatus according to the invention provides that a nozzle part is connected to the base body in such a manner that fluid can flow from the feed channel - directly - into the channel of the nozzle arrangement. A compact layout results thereby.

[0015] According to an alternative embodiment, it is suggested that the nozzle arrangement is formed as a slot nozzle arrangement and/or that the base body and/or the slot nozzle arrangement comprises a number of segments, which are arranged adjacent to one another. By such a segmented design of the base body and/or the slot nozzle arrangement, the size of the apparatus can be adapted to the respective use. It is advantageous in this case that a base body segment comprises a feed channel, and that a valve arrangement is assigned to each base body segment, so that fluid can be fed to each segment individually. The first and second nozzle part are thereby preferably respectively formed as one piece.

[0016] An alternative embodiment is characterised in that the length of the manifold formed in the nozzle part is limited laterally by a respective closing body, which can be moved and fixed within the manifold in a motor-driven manner. An individual adaptation of the length of the slot-shaped outlet opening can thereby take place, by positioning the lateral closing bodies in such a manner that the desired application width is achieved. The closing bodies can preferably be moved in a motor-driven manner, for example by means of an electromotive chain or a drive belt. The closing body is fixed after the adjustment. For this, a separate fixing element, for example a screw, can be provided, or a fixing already results through the motor.

[0017] The invention is described in the following by means of a preferred embodiment. It shows:

figure 1

a side view of an embodiment of a dispensing apparatus according to the inven- tion with a nozzle arrangement according to the invention;

figure 2

a rear view of the apparatus according to figure 1;

figure 3

a sectional view of the apparatus according to figure 1 along A-A;

figure 4

a sectional view of the apparatus according to figure 1 along A-A in the opened position;

figure 5

a nozzle arrangement according to figure 4 according to the invention in the closed position;

figure 6

a nozzle arrangement according to the invention in the closed position in pers- pective; and

figure 7

a nozzle arrangement according to the invention in the opened position in pers- pective.

[0018] The apparatus with the nozzle arrangement shown in the figures serves for dispensing fluids, especially hot melt adhesive, to different substrates. Other fluids can be dispensed and applied, especially applied in a planar manner. Alternative embodiments can also be realised, with which fluids can be applied in a purl seam manner or in strips or in other forms.

[0019] The apparatus shown in figures 1 to 3 for dispensing a fluid comprises a base body 2, which is also called manifold, and a nozzle arrangement 4, which is formed as a slot nozzle arrangement in the example and is screwed together with the base body. The base body 2 is attached to carrier structures 6, for example a carrier profile, and can be assembled and positioned in a stationary manner, so that fluid dispensed from the apparatus can be applied to a substrate which is movable relative to the apparatus.

[0020] The base body 2 can be connected to an adhesive source, not shown, in the form of a melting device or the like by means of one or several connections 8, so that adhesive or another fluid can be introduced into a fluid feed channel 10, which is formed in the base body 2. The feed channel 10 runs in the longitudinal direction of the apparatus 1. A valve arrangement 12 for selectively interrupting or releasing the fluid flow is arranged in the sectional plane A-A according to figure 1. The nozzle arrangement 12 comprises a so-called control part, with which a valve body can be moved pneumatically or electrically relative to a valve seat in a basically known manner, to selectively interrupt or release the fluid flow. A fluid-conducting connection between the channel 10 and the free flow cross sections of the valve arrangement 12 is formed by a bore, so that fluid can flow from the feed channel 10 into the space 14 (see figure 3) when the valve arrangement 12 is opened. The space 14 communicates with a bore 16, which is formed in the base body 2. The bore 16 again communicates with a - in figure 3 vertical - bore 18 within the base body 2. Through these channels, fluid can be conducted through the feed channel 10 into the space 14 through the bore 16 and 18 to the nozzle arrangement 4, when the valve arrangement 12 is opened. The control part of the valve arrangement 12 is actuated pneumatically in the embodiment. Pressurised air can be introduced for this, which acts on a piston for the movement of the valve body relative to the valve seat.

[0021] The nozzle arrangement 4 comprises two nozzle parts 20, 22. The first nozzle part 20 comprises a bore or channel 24, through which fluid can be introduced from the base body 2, more precisely through the bore 18, which is in fluid connection with the channel 24. The channel 24 leads into a distribution channel or manifold 26 formed in the nozzle arrangement 4. The manifold 26 is formed in the first nozzle part 20 in the embodiment and has the form of a trench or groove. The manifold 26 is rectangular in its cross section in the embodiment, but other forms can also be realised. Fluid can be distributed over an essential part of the length of the nozzle arrangement 4 by means of the manifold 26. The manifold 26 is in fluid connection with an essentially slot-shaped outlet channel 28 (figure 3), which leads into a slot-shaped outlet opening 30 for dispensing fluid from the nozzle arrangement 4 and thereby the apparatus 1. The outlet channel 28 is, as depicted in figure 3, limited by a section of the first nozzle part 20 and a section of the second nozzle part 22. The outlet channel 28 is formed by a slot between the two nozzle parts 20, 22. In a manner not shown, the nozzle arrangement could also not be formed as a slot nozzle arrangement, but as a nozzle arrangement with a plurality of for example cylindrical outlet channels with circular outlet openings for dispensing fluid.

[0022] As can be seen in figures 3, 5 and 6, the nozzle parts 20, 22 are formed as longitudinal essentially plate-shaped components. The nozzle parts 20, 22 are formed in such a manner in the region of the outlet channel 28, that the outer contour of the nozzle arrangement tapers towards the outlet opening 30. Two outer surfaces 23, 25 of the nozzle parts 20, 22 are thereby arranged essentially V-shaped to one another.

[0023] If necessary, several valve arrangements 12 and channels for feeding the fluid into the manifold 26 of the nozzle arrangement 4 can be provided according to the representation according to figure 3, so as to be able to carry out a fluid feed to the nozzle arrangement 4 at several locations. The number of the valve arrangements 12 and thereby feed devices can be determined in dependence on the total length of the nozzle arrangement.

[0024] As can be seen in figures 1 and especially 2, the base body 2 has a plurality of adjacent base body segments 2', as is shown in figure 2, which are arranged adjacent to one another in the longitudinal direction. Each segment 2' comprises a section of the feed channel 10. The individual sections of the feed channel 10 are sealed to one another in the region of the contact surfaces between the segments 2'. A seal can be provided for this. The individual sections of the feed channel 10 can for example be formed as pipe sections, which are formed at their ends in such a manner that they can be plugged into one another like a pipe sleeve. By the segmented layout of the base body, its length can be varied for the respective use and the total length of the apparatus can be varied in a simple manner.

[0025] The nozzle parts 20, 22 are respectively formed as one piece in the embodiment, so that several segments 2' of the base body 2 are assigned to the two one-piece nozzle parts 20, 22. The nozzle arrangement 4 could also be formed in a segmented manner, not shown. In this case, the two nozzle parts 20, 22 would comprise segments which are respectively separated from one another, which are arranged in an adjacent manner. In the embodiment, a valve arrangement 12 is not assigned to each segment 2' of the base body, but only to one segment 2', as explained previously. Alternatively, a valve arrangement could however be assigned to several or each individual segment 2', so as to introduce fluid to each segment 2' in the manner shown in figure 3 to the manifold 26 of the nozzle arrangement 4. This could for example be sensible if a particularly even fluid feed in the nozzle arrangement 4 is desired, or if individual regions are to be supplied individually with adhesive. In this case, the individual valve arrangements 12 could be actuated individually, that is, brought into the opened or closed position.

[0026] The layout of the nozzle arrangement 4 according to the invention can be depicted particularly well by means of figures 3 to 7. Figures 4 to 7 show in particular that the first nozzle part 20 and the second nozzle part 22 are arranged in a pivotal manner to one another. In figures 4 and 7, the nozzle part 22 is depicted in a pivoted manner or pivoted away, while figures 5 and 6 show the nozzle parts 2, 22 in a relative position to one another, in which the manifold 26 is closed by the nozzle part 22. In the embodiment, the nozzle part 22 is arranged in a pivotal manner by means of a joint, for example a hinge joint 32. Alternatively, a further component could be interposed between the nozzle parts 20, 22, so that an arrangement is realised which is pivotal relative to one another. The joint 32 comprises a positioning pin 34, which is cylindrical in the embodiment and which is arranged with one half in a recess 36 in the nozzle part 20. The recess 34 is adapted to the form of the pin 34. The pin 34 lies in a recess 38 with its other half, which is formed in the nozzle part 22. A precise positioning of the upper nozzle part 22 in relation to the lower nozzle part 20 is ensured by the pin 34 and the recesses 36, 38 in the closed position shown in figures 5 and 6, so that the nozzle parts 20, 22 are arranged to one another in a precise manner, and that a reliable seal results between the parts, and a precise formation of the slot-shaped outlet channel 28 between the nozzle parts 20, 22, and a precise formation of the slot-shaped outlet opening 30 at the end of the outlet channel 28.

[0027] The two nozzle parts 20, 22 could also be arranged relative to one another in a pivotal manner by means of other joints, in a manner not shown, by using other pivot joints, hinge joints or the like.

[0028] The nozzle parts 20, 22 are additionally secured to one another by several bolts 40 in the closed operating position (figures 3, 5 6) and are screwed and clamped to one another. The bolts 40 with their widened head are arranged within a recess with their lower end section in the figures, which recess is formed in the nozzle part 20. Nuts 42 can be screwed on in their upper threaded section, possibly with interposition of retaining rings 44. The nozzle parts 20, 22 are clamped to one another in the clamped state. Sealing elements such as sealing profiles or especially smooth sealing surfaces can be provided adjacent to the manifold 26, which are pressed to one another by means of bolts 40 in such a manner that fluid does not escape from the manifold 26 and is safely conducted into the outlet channel 28. The clamping of the nozzle parts 20, 22 can be loosened again by loosening the nuts 42. The pivoting of the nozzle parts 20, 22 relative to one another can be realised after the loosening. Such a pivoting can take place around the pivot axis defined by the pins 34. Even in the case that a hinge joint is used which attaches the nozzle parts 20, 22 in a pivoting manner, the one nozzle part 22 can be pivoted upwards around the axis defined by the hinge joint relative to the nozzle part 20 and fold approximately into the position shown in figure 7 and further fold out therefrom. As shown in figures 4 and 7, the bolts can also be pivoted away relative to the nozzle part 20.

[0029] As can be seen particularly in figures 6 and 7, bolts 40 are arranged within a recess 46, which are formed in the first nozzle part 20 and the second nozzle part 22. The recess 46 is formed by a first slot 48, which is formed at the first nozzle part 20 in its boundary area, and a second slot 50, which is formed at the second nozzle part 22 in its boundary area. A slot-shaped recess 46 is formed through both slots 48, 50 in the closed state (figures 3, 5 and 6), in which the bolts 40 are arranged. The slots 48, 50 are formed as grooves 23, 22, especially by milling. The bolts 40 can thereby be moved within the slots 48, 50 forming the recess 46 when the nuts 42 are loosened and rotated to the positions shown in figures 4 and 7.

[0030] In one embodiment, the bolts 40 with their end section, which is opposite the threaded section, onto which the nuts can be screwed, can be pivotally attached to the first nozzle part 20 by means of a pin. For this, each bolt 40 can have a cylindrical pin assigned thereto, which is plugged through a cylindrical transverse bore in the end section of the bolt 40, attached to the nozzle part 20. The bolts 40 would thereby be attached to the nozzle part 20 in a pivotal manner and can be pivoted from the position shown in figure 7 into the position shown in figure 5 and vice versa. This results in the advantage that the bolts 40 remain at the nozzle part 20 during disassembly, and do not have to be placed completely manually into the slots 48, 50 during assembly. As with this embodiment, the pin would extend transversely through the slot 48, and through the transverse bore in the bolt 40.

[0031] As shown in figures 6 and 7, at least one stop element 52, 54 is provided, which limits the ability to pivot of the nozzle part 20 relative to the nozzle part 22. The stop element 52 is formed as a block and is attached to the nozzle part 20 by means of a screw connection. It has an oblique stop surface 56 at its upper side, which can be brought into contact with a surface of the nozzle part 22, and thus serves as a stop. A further stop element 54 is attached to the second nozzle part 22 by means of a screw connection. It is laterally in contact with the stop element 52, so that an axial displacement in the direction of the longitudinal axis of the nozzle arrangement is limited. One or two further corresponding stop elements 52, 54 can be provided on the opposite side of the nozzle arrangement, so that a stop for limiting the ability to fold and also a stop for limiting the axial ability for displacement is also present on this side..

[0032] As can be seen well in figures 4, 6 and 7, the manifold 26 has the form of a groove with a rectangular cross section. Other forms would also be feasible, for example a partially circular form in its cross section. The manifold 26 could also be formed by two opposite grooves in the nozzle part 20 and opposite in the nozzle part 22, so that altogether an essentially cylindrical manifold 26 with a circular cross section would result.

[0033] As can be seen in figures 1 and 3, the entire length of the manifold 26 formed in the nozzle arrangement 4 is limited laterally by a closing body on each side of the manifold 26. A closing body 60 is positioned on each side of the manifold 26, and completely seals the manifold 26 laterally. The closing bodies 60 can be moved or displaced within the manifold by means of a motor, especially an electric motor (not shown), so that the effective length of the manifold 26 and thus the application width of the slot nozzle arrangement can be changed. The closing bodies 60 are coupled to a chain, not shown in detail, for this purpose, which is placed around a chain wheel 62, which is mounted at the base body 2 in a rotatable manner. The motor is further attached to the base body 2 or the holding structure 6 in such a manner that its drive shaft is coupled to the chain wheel 62, so that the closing bodies 60 can be moved axially within the manifold 26 by means of the chain when the motor is switched on and fixed in a desired position in that the inertness of the motor fixes the closing bodies in their respective position.

[0034] It is alternatively feasible that the lateral closing bodies 60 can be moved manually, for example with the aid of threaded spindles or other slide mechanisms. In a manner not shown in detail, slot-shaped projections can be formed laterally to the closing body 60, which extend partially or completely into the slot-shaped outlet channel 28 to limit it laterally. Such a a projection extends at the most up to the outlet opening 30.

[0035] As is shown in figure 4 in an exemplary manner, the second nozzle part 22 can also be removed further from the nozzle part 20 after a first pivoting, if more space is needed for cleaning or service. The nozzle part 22 would subsequently again be placed on the nozzle part 20, so that the positioning pin 34 again reaches the recesses 38, 36 and provides a defined positioning of the nozzle parts 20, 22 relative to one another. The nozzle part 22 can then be folded on the nozzle part 20 for pivoting around the axis formed by the positioning pin 34, and be brought into the closing position.

Claims

1. Nozzle arrangement (4) for an apparatus (1) for dispensing fluid, especially adhesive, with a first nozzle part (20),
a second nozzle part (22), which can be attached to the first nozzle part (20),
at least one channel (24) formed in the first nozzle part (20) and/or the second nozzle part (22), into which fluid can be introduced,
and at least one outlet opening (30) for dispensing fluid, which can be brought into fluid connection with the at least one channel (24),
characterised in that the first nozzle part and the second nozzle part are arranged to one another in a pivoting manner.

2. Nozzle arrangement (4) according to claim 1,
characterised in that it is formed as a slot nozzle arrangement and comprises at least one essentially slot-shaped outlet opening (30), and that the outlet opening (30) is limited at least partially by a section of the first nozzle part (20) and a section of the second nozzle part (22).

3. Nozzle arrangement (4) according to claim 1 and/or 2,
characterised in that the first nozzle part (20) and the second nozzle part (22) are connected to one another by means of a hinge joint (32).

4. Nozzle arrangement (4) according to at least one of the preceding claims,
characterised in that the ability to pivot is limited by at least one stop element (52, 54).

5. Nozzle arrangement (4) according to at least one of the preceding claims,
characterised in that the first nozzle part (20) and the second nozzle part (22) can be clamped to one another by means of at least one bolt (40).

6. Nozzle arrangement (4) according to claim 5,
characterised in that the at least one bolt (40) is arranged at least partially within a recess (46), which is formed in the first nozzle part (20) and/or the second nozzle part (22).

7. Nozzle arrangement (4) according to claim 6,
characterised in that the recess (46) is formed essentially by a slot (48) formed at the first nozzle part (20) and a slot (50) formed at the second nozzle part (22).

8. Nozzle arrangement (4) according to at least one of the preceding claims,
characterised in that a manifold (26) is formed in the first nozzle part (20) and/or the second nozzle part (22), which manifold can be brought into fluid connection with an essentailly slot-shaped outlet channel (28), which is limited by a section of the first nozzle part (20) and a section of the second nozzle part (22) and which leads into the essentially slot-shaped outlet opening (30).

9. Nozzle arrangement (4) according to at least one of the preceding claims,
characterised in that the manifold (26) is formed as a groove in the first nozzle part (20) and the second nozzle part (22) closes the manifold (26) in the closed position.

10. Apparatus (1) for dispensing fluid, especially adhesive, to a substrate,
with a base body (2) comprising a fluid feed channel (14) which can be connected to a fluid source,
a nozzle arrangement (4) comprising a channel (24), which can be connected to the feed channel (14) and an outlet opening (30) for dispensing fluid, wherein the nozzle arrangement (4) comprises a first nozzle part (20) and a second nozzle part (22), which can be attached to the first nozzle part (20),
and a valve arrangement (12) for selectively interrupting or releasing the fluid flow, characterised in that the first nozzle part (20) and the second nozzle part (22) are arranged to one another in a pivoting manner.

11. Apparatus (1) according to claim 10,
characterised in that the nozzle arrangement (4) is formed according to at least one of the preceding claims 1-9.

12. Apparatus (1) according to claim 10 and/or 11,
characterised in that a nozzle part (20) is connected to the base body (2) in such a manner that fluid can flow from the feed channel (14) into the channel (24) of the nozzle arrangement (4).

13. Apparatus (1) according to claim 10, 11 or 12,
characterised in that the nozzle arrangement (4) is formed as a slot nozzle arrangement (4) and/or the base body (2) and/or the slot nozzle arrangement (4) comprises a number of segments, which are arranged adjacent to one another.

14. Apparatus (1) according to claim 13,
characterised in that a base body segment (2) comprises a feed channel (14),
and that a valve arrangement (12) is assigned to each base body segment (2'), so that each segment can individually be fed with fluid.

15. Apparatus (1) according to at least one of the preceding claims,
characterised in that the length of the manifold (26) formed in the nozzle part is limited laterally by a respective closing body (6), which can preferably be moved and fixed within the manifold (26) by means of a motor.

Drawing