DEVICE FOR SPRAYING ADHESIVE AND METHOD

Abstract

A device for spraying adhesive onto a substrate or workpiece, for example, an automotive workpiece, includes at least one spray nozzle for discharging the adhesive having at least two adhesive inlets and at least two regions of adhesive outlets. One of the regions of adhesive outlets which can be supplied separately with a width of less than 25 mm is connected to precisely one of the adhesive inlets.

Claims

1. A device for spraying adhesive onto a substrate or workpiece, for example, an automotive workpiece, comprising at least one spray nozzle for discharging the adhesive having at least two adhesive inlets and at least two regions of adhesive outlets, wherein one of the regions of adhesive outlets which can be supplied or switched separately with a width (b) of less than 25 mm is connected to precisely one of the adhesive inlets.

2. The device as claimed in claim 1, wherein the spray nozzle comprises a plurality of parallel plates which as a result of recesses which are arranged therein form separate channels between a respective adhesive inlet and a respective region of adhesive outlets.

3. The device as claimed in claim 1, wherein one of the regions of adhesive outlets which can be supplied or switched separately and which has a width (b) of less than 25 mm, and which is connected to precisely one of the adhesive inlets has a width (b) of less than 20 mm, preferably less than 15 mm, more preferably less than 10 mm.

4. The device as claimed in claim 1, wherein the plurality of parallel plates which comprises the spray nozzle and which, as a result of recesses arranged therein form separate channels between an adhesive inlet and a region of adhesive outlets in each case, have an inner guide plate which has two separate, in particular axially symmetrical, recesses through which adhesive can flow.

5. The device as claimed in claim 4, wherein the guide plate is directly or indirectly associated with an outlet plate, having outlets for the adhesive.

6. The device as claimed in claim 1, wherein the device comprises a plurality of in particular identical spray nozzles which are preferably arranged transversely relative to the application direction (A), in particular directly, beside each other, more preferably orientated in the same direction.

7. The device as claimed in claim 6, wherein each of the nozzles has an individual separate housing which is in particular isolated from the others.

8. The device as claimed in claim 1, wherein there is associated in each case, in particular clearly, with the two adhesive inlets of a spray nozzle an individual switching valve which is preferably constructed separately from the spray nozzle, wherein there is preferably provision for the two switching valves, which are each associated with one of the two adhesive inlets of a spray nozzle, to be arranged in an overlapping manner with respect to the contour of the spray nozzle.

9. The device as claimed in claim 8, wherein two switching valves or the switching valve modules thereof, which are each associated with one of the two adhesive inlets of a spray nozzle are orientated in such a manner, in particular in parallel planes, that they form an angle of attack (), wherein there is preferably provision for all the switching valves or the switching valve modules thereof of the device to be arranged in one of these two orientations.

10. The device as claimed in claim 1, wherein a plurality of switching valves of the device are accessible via a common opening mechanism, in particular in the form of a hinge.

11. The device as claimed in claim 1, wherein a plurality of spray nozzles are fitted to a common application head of the device, on which a common pump station for the adhesive, is mounted, in particular without hoses.

12. A method for spraying adhesive onto a substrate or workpiece, for example, an automotive workpiece, comprising the steps of: supplying adhesive to a spray nozzle through at least two adhesive inlets which can be supplied or switched separately; separately directing the adhesive in the nozzle to two regions of adhesive outlets; and applying the adhesive to the substrate or workpiece by means of discharge through one of the regions of adhesive outlets with an application width (b) of less than 25 mm, in particular less than 20 mm, furthermore in particular less than 15 mm, furthermore in particular less than 10 mm.

Description

[0066] Other advantages will be appreciated from the following description of the Figures and the corresponding Figures. In the drawings:

[0067] FIG. 1: shows the result of a method already described from the prior art for applying adhesive strips to a motor vehicle carrier component,

[0068] FIG. 2: shows in a view approximately in accordance with FIG. 1 the result of a method according to the invention using a device according to the invention with a higher number of adhesive strips, each with a smaller width in a linear orientation,

[0069] FIG. 3: is a highly schematic, isometric outer view of a portion of a device according to the invention, in particular in the form of an adapter, wherein one of the nozzles, for the sake of clarity, is illustrated in the disassembled state,

[0070] FIG. 4: shows the portion of the device according to FIG. 3 in a view opened via a hinge,

[0071] FIG. 5a: is a front view of the portion of the device according to FIG. 3, approximately in accordance with the view arrow V in FIG. 3, with the nozzles fully assembled,

[0072] FIG. 5b: is a section through FIG. 5a along the line of section A-A,

[0073] FIG. 5c: is a section through FIG. 5a along the line of section B-B in FIG. 5a,

[0074] FIG. 6: is an isometric, highly schematic view of an application head with the pump station assembled,

[0075] FIG. 7a: is a rear, detailed view of a disassembled spray nozzle,

[0076] FIG. 7b: is a front view of the spray nozzle according to FIG. 7b and

[0077] FIG. 8: is an exploded view of the spray nozzle illustrated in FIG. 7 with a plurality of parallel plates.

[0078] Prior to the following description of the Figures, it should be noted that identical or comparable components are sometimes provided with identical reference numerals, where applicable with the addition of lower case letters or apostrophes. The patent claims which follow the description of the Figures therefore sometimes have only the corresponding reference numerals without additions.

[0079] In the Figures, FIG. 2 initially shows the result of a method according to the invention for spraying adhesive using a device 10 according to the invention which is described in even greater detail in the following Figures.

[0080] FIG. 2 shows the same workpiece 11 as FIG. 1, that is to say, for example, a carrier component from the automotive sector in the manner of a door trim, in particular with a recess 13. FIG. 2 shows that the applied adhesive strips 12 have a smaller width b than the width b according to the prior art in accordance with FIG. 1.

[0081] The width b of the adhesive strip according to FIG. 2 may, for example, be less than 25 mm, in particular less than 20 mm, furthermore in particular less than 15 mm, for instance, approximately 12.5 mm.

[0082] As a result of the smaller width b, per width portion of the workpiece 11 there are naturally more adhesive strips 12 applied. The adhesive strips 12 have in addition the advantage that they are all orientated in a linear manner in the application direction A.

[0083] In contrast to FIG. 1, therefore, the spray nozzles according to FIG. 2 do not need to be guided along a curved path, but instead only along a straight line. As a result of the smaller width b and consequently a better resolution of the application, it is possible, for example, for the recess 13 to be taken into account and moved closer to the edges without curved paths being required. The application pattern is sufficiently good and extends sufficiently close to the recess 13.

[0084] In addition, the edges of the workpiece 11 may be included in such a manner that it is possible to work substantially parallel with the edges thereof so that occurrences of overlapping of the adhesive paths 12 can substantially be avoided.

[0085] Also as a result of the avoidance of curved paths, a more rapid cycle time can be achieved. In the embodiment according to FIG. 2, it is, for example, possible to use an application head which has four nozzles or nozzle modules. Each of these spray nozzle modulesas will be set out further belowcan be associated with two adhesive inlets and accordingly also two regions of adhesive outlets. This consequently leads to the eight illustrated adhesive paths 12 using an application head with four spray nozzles which each have two regions of adhesive outlets which can respond independently of each other.

[0086] In the embodiment, the adhesive strips 12 comprise the applied adhesive 15, which may, for example, be a hot melt adhesive.

[0087] In order to produce the application pattern according to FIG. 2, it is possible, for example, to use an application head 16, as illustrated, for example, in FIG. 6. This application head 16 has according to FIG. 6 in particular a front portion 17 which is illustrated to an enlarged scale in FIG. 3.

[0088] FIG. 3 illustrates in this instance that the front portion 17 comprises four spray nozzles 18a to 18d which are mounted beside each other (in FIG. 3, the first spray nozzle 18a is illustrated in a non-assembled state only for reasons of clarity).

[0089] The spray nozzles 18 are orientated in an identical manner and arranged or mounted directly beside each other in a transverse direction Q, transversely relative to the application direction A. Each of the nozzles 18 has two separate adhesive inlets 19 or 19. Furthermore, an inlet 20 for spray air is provided on each nozzle 18. The inlets 19, 19 and 20 (which in FIG. 3 can be seen naturally only for the spray nozzle 18a) are supplied via corresponding inlets 21 or 21 (for the adhesive) and 22 (for the spray air) on the front portion 17 of the application head 16.

[0090] Each of the nozzles 18 is connected via one of the inlets 19 or 19 thereof or via a channel system which is not yet illustrated in FIG. 3 to one of the switching valves 23a to 23d illustrated in FIG. 3. The switching valves 23 are in the context of this application also referred to as switching modules.

[0091] In addition to the four switching valves 23a to 23d, however, the front portion 17 has four additional switching valves 23a to 23d. These are arranged in a concealed manner and can be seen, for example, in Figure 4, which shows, for example, a rear view of the front portion 17 illustrated in FIG. 3.

[0092] The front portion 17 is according to FIG. 4 illustrated in an open position in which the switching valves 23 can be accessed better or even at all, for example, for maintenance or replacement operations.

[0093] To this end, the front portion 17 provides a hinge 24 which provides an opening mechanism for the front portion 17. The front portion 17 may comprise in this context, for example, a securing portion 25 and an assembly portion 26 which are connected to each other via the hinge 24 and which are constructed so as to be able to be pivoted relative to each other.

[0094] FIG. 4 illustrates not only that the front portion 17 is a front portion which can be opened. Instead, FIG. 4 additionally illustrates that the front portion 17 is constructed on the whole as an application adapter. Accordingly, the application head 16 or the entire device 10 thus comprises an application adapter 17.

[0095] In this context, the application adapter 17 is an adapter because it enables the use of the illustrated nozzles 18 with two adhesive inlets 19, 19 in a conventional base portion of the application head 16 with in principle only a single adhesive supply per nozzle. FIG. 4 thus illustrates that per nozzle 18 only one adhesive supply 27a to 27d is provided. This supply is divided or split in the manner of a switch in the adapter 17, in particular in the securing portion 25, so that two outlets 21, 21 can be supplied via the supply 27a to 27d per nozzle 18a to 18d.

[0096] Each supply 27 or each nozzle 18 is in this instance associated with an offset pair of the switching valves 23 or 23. In this context, there is arranged upstream of the two adhesive inlets 19 or 19 precisely one switching valve 23 or 23 which controls or switches the supply of this inlet 19 or 19 with adhesive. In the illustrated embodiment, the switching valve 23a is arranged, for example, upstream of the adhesive inlet 19 of the spray nozzle 18a and the switching valve 23a is arranged upstream of the adhesive inlet 19 of the nozzle 18a.

[0097] This offset arrangement of the two rows of switching valves 23a to 23d and 23a to 23d enables in this instance a particularly space-saving arrangement which in any case to some extent FIG. 5 also illustrates:

[0098] Thus, FIG. 5a is a front view of the front portion 17 of the application head 16 or the device 10 in which only the first row of switching valves 23a to 23d can be seen. The sections through FIG. 5a A-A (cf. FIG. 5b) and B-B (cf. FIG. 5c) illustrate, however, the tilted and consequently space-saving arrangement of the two switching valve rows with respect to each other by way of example, with reference to the switching valves 23d and 23d. In this context, the two switching valve rows enclose an angle of attack . In this instance, FIG. 5 also shows that the two switching valves 23 or 23 of a switching valve pair which is associated with a nozzle 18 overlap in the viewing direction approximately in accordance with FIG. 5a. In FIG. 5a, as already noted, the switching valve 23d cannot be seen. However, the axes of section A-A and B-B then illustrate the overlapping since they relate substantially to the center axes of the switching valves (modules) 23d to 23d.

[0099] FIGS. 5b and 5c further illustrate in overview that both switching valves 23 or 23 which are associated with a common nozzle 18 are supplied by a common channel 28 which itself in turn is supplied with adhesive by one of the supplies 27 according to FIG. 4.

[0100] However, the two switching valves 23d and 23d then have separate supply channels 29 and 29 which are isolated from each other to the corresponding spray nozzle 18. At least two switching valves 23 or 23 are thus always associated with a nozzle 18.

[0101] FIG. 6 illustrates that the front portion 17 receives the adhesive (in particular via the mentioned supplies 27) from a pump station 30 which is securely mounted on the application head 16, in particular without adhesive-guiding hoses being interposed.

[0102] In addition to adhesive, however, spray air can naturally also be supplied to the application head 16 via the pump station 30. For example, the pump station 30 may also contain a corresponding valve arrangement for the spray air and/or naturally pumping means, such as gear pumps, for the adhesive.

[0103] As a result of the fact that no hoses are used between the application head and pump station or precision pump, but instead the pump station 30 is mounted directly on the application head 16, there can be achieved much more rapid quantity regulation times of the adhesive which, for an application pattern, as illustrated in FIG. 2, are absolutely necessary: the two regions (which are yet to be described) of adhesive outlets of a single spray nozzle 18as describedhave to be able to be switched independently of each other. In principle, although the switching valves 23 or 23 are provided therefor, the total quantity of adhesive must be able to be varied for the different switching states. For example, in total less adhesive should be discharged from a nozzle 18 if only one of the regions of adhesive outlets thereof is active. If the pump station 30 did not exist or it could not be regulated, no strips 12 with a homogeneous application quantity would be possible.

[0104] So that an optimum supply is achieved, the pump station is integrated directly in the device, in particular mounted on the application head 16. The supply component 31 of the application head 16 may then ensure direction of the adhesive and the spray air onto the front portion 17 or the module 17.

[0105] FIG. 7 then shows two large isometric illustrations of a spay nozzle 18 of the device 10 according to the invention, wherein the rear view according to FIG. 7a once again illustrates the two adhesive inlets 19 or 19 and the spray air inlet 20. Furthermore, however, a plate-like construction of the plate-like spray nozzle 18 can also already be seen. Between an inlet plate 32 and an end or termination plate 33 it is thus possible to see a plurality of parallel narrow plates which, in particular at the lower side of the nozzle 18, form a plurality of adhesive outlets 34a to 34f.

[0106] These adhesive outlets 34 are in this instance associated in groups with the two adhesive inlets 19 or 19 so that the nozzle 18 shown according to FIG. 7 forms a total of two regions 35 and 35 of adhesive outlets 34.

[0107] The connection between the individual adhesive outlets 34 and the two adhesive inlets 19 or 19 of a nozzle 18 is then shown in the exploded illustration according to FIG. 8: there is first provided an inlet plate 32 with the adhesive inlets 19 or 19 which are associated therewith and which are formed therein (the attachments of the inlets 19 or 19 may, as illustrated, be separate components or constructed integrally with the plate 32).

[0108] In the flow direction F there is arranged directly downstream of the inlet plate 32 a guide plate 36 which in particular has two axially symmetrical recesses 37 or 37 for directing the adhesive. The recesses 37 or 37 are in the embodiment in particular constructed in a kidney-like manner.

[0109] In the flow direction F there then follows a second guide plate 38 which has a plurality of smaller recesses for associating the adhesive on the adhesive outlets 34. Finally, in the flow direction F there follows an outlet plate 40 having a plurality of edge recesses which in the embodiment illustrated constitute the adhesive outlets 34a to 34f. Each adhesive outlet 34 is surrounded in a flanking manner by two spray air outlets 41 or 41 which, as will be described below, are supplied with spray air and which are intended to carry the discharged adhesive in a desired path onto the workpiece 11 or the substrate.

[0110] FIG. 8 consequently illustrates as an interim conclusion that the three left adhesive outlets 34 which are associated with the outlet plate 40 are associated with the recess 37 of the plate 36 and consequently the adhesive inlet 19 of the nozzle 18. The three adhesive outlets 34 in the outlet plate 40 which are arranged on the right are in contrast associated with the recess 37 in the guide plate 36 and consequently with the other adhesive inlet 19 of the nozzle 18.

[0111] Finally, the guiding of the spray air in the nozzle 18 is further intended to be explained with reference to FIG. 8: the spray air thus passes through the inlet 20 of the inlet plate 32 into the nozzle and is first directed through congruent passages 42, 42, 42 and 42 in the plates 36, 38, 40 and 43 as far as an air direction plate 44. In the air direction plate there is a redirection of the spray air, downward with respect to FIG. 8, and then back through the lower recesses 50 of the plate 43 into the spray air recesses 41 to 41 of the outlet plate 40.

[0112] For example, there may be provision in this instance for both regions 35 and 35 to be constantly supplied with spray air by adhesive outlets, although only one of the two regions 35, 35 actually discharges adhesive 15. However, there may in principle also be provided a separate switching of the two regions 35, 35 with respect to the spray air.

[0113] It should finally be noted that in the Figures both the width of the application strip and the width of a region of outlets purely for reasons of simplicity is provided with the reference numeral d (the region width thus corresponds in the example substantially to the strip width).