CASTING DEVICE FOR APPLYING A FOAMING REACTION MIXTURE

Abstract

The invention relates to a casting device for applying a foaming reaction mixture, to at least a partial width of a cover layer, wherein the casting device comprises: a supply connection for feeding in the reaction mixture; at least one exit slit extending in a transverse direction for the exiting of the reaction mixture; two slit plates arranged opposite one another, wherein a slit space extends between the slit plates in a vertical direction above the exit slit. A supply channel connected to the supply connection is formed between the slit plates, which closes off the slit space above the exit slit in the vertical direction The supply channel has a channel cross-section, the main dimension of which is larger that the width of the slit space. The reaction mixture can be introduced into the slit space to distribute the reaction mixture over the length of the supply channel.

Claims

1. A pouring device for applying a foaming reaction mixture comprising at least polyol and isocyanate over at least part of a width of a facing layer, for producing a composite element, wherein the pouring device comprises: a feed port for feeding in the reaction mixture, at least one outlet slot extending in a transverse direction for discharge of the reaction mixture, two mutually opposingly arranged slot plates, wherein a slot space extends between the slot plates in a vertical direction above the outlet slot, wherein a feed duct connected to the feed port is formed between the slot plates, wherein the feed duct terminates the slot space above the outlet slot in the vertical direction, wherein the feed duct comprises a duct cross-section with a main dimension which is greater than a width of the slot space, such that the reaction mixture may be introduced into the slot space distributed over a length of the feed duct.

2. The pouring device as claimed in claim 1, wherein the duct cross-section is configured to become smaller as a distance from the feed port increases.

3. The pouring device as claimed in claim 1, wherein the slot space has a width which is formed constantly over substantially the entire two-dimensional extent of the slot space between the slot plates.

4. The pouring device as claimed in claim 1, wherein the feed duct is curved, such that a height of the slot space above the outlet slot becomes smaller as a distance from the feed port increases.

5. The pouring device as claimed in claim 4, wherein the curvature of the feed duct increases in magnitude as a distance from the feed port increases.

6. The pouring device as claimed in claim 1, wherein the changing duct cross-section of the feed duct and/or the curvature of the feed duct and/or the configuration of the slot space are determined in such a way that the discharge velocity of each element of volume of the reaction mixture has the same velocity value over a length of the outlet slot.

7. The pouring device as claimed in claim 1, wherein the changing duct cross-section of the feed duct and/or the curvature of the feed duct and/or the configuration of the slot space are determined in such a way that, relative to a length of the outlet slot, each element of volume of the reaction mixture displays the same transit time from the feed port to discharge from the outlet slot.

8. The pouring device as claimed in claim 1, wherein a length of the feed port and/or the length of the feed duct and/or a height of the slot space in the vertical direction above the outlet slot are determined in such a way that the transit time of the reaction mixture is less than the reaction time.

9. The pouring device as claimed in claim 1, further comprising adjusting means, wherein a width of the outlet slot is adjustable, and wherein a plurality of adjusting means are distributed over the length of the outlet slot.

10. An installation for applying a foaming reaction mixture at least comprising polyol and isocyanate over at least part of the width of a facing layer, for producing a composite element, comprising a plurality of pouring devices as claimed in claim 1, wherein the outlet slots of the pouring devices extend in a common transverse direction or over an arch over the facing layer.

11. The installation as claimed in claim 10, wherein the slot plates of the plurality of pouring devices are configured together in one piece on each side of the slot space.

12. The installation as claimed in claim 10, wherein the ends remote from the feed ports of the feed ducts of the plurality of pouring devices adjoin one another.

13. The installation as claimed in claim 10, wherein the installation comprises a gas loading device.

14. The installation as claimed in claim 10, wherein gas loading is performed using a gas selected from the group consisting of air, nitrogen, carbon dioxide, noble gas, and combinations of any thereof.

15. The installation as claimed in claim 13, wherein the reaction mixture is loaded with a gas.

16. The installation as claimed in claim 10, wherein gas loading is performed using a gas selected from the group consisting of argon, helium, and combinations of any thereof.

Description

PREFERRED EXEMPLARY EMBODIMENT

[0029] Further measures which improve the invention are described in greater detail below with reference to the figures, together with the description of a preferred exemplary embodiment of the invention. In the figures:

[0030] FIG. 1 is an overall view of the installation with a pouring device and facing layer feed and a double belt conveying installation,

[0031] FIG. 2 is a perspective representation of a slot plate 14 from that side which two-dimensionally delimits the slot space,

[0032] FIG. 3 a transversely sectional view of the pouring device with two slot plates arranged on one another, forming the slot space between the slot plates,

[0033] FIG. 3a shows a modified embodiment of the outlet slot with slot lips formed thereon,

[0034] FIG. 4 is a perspective view of a continuous slot plate, which forms a plurality of individual pouring devices and

[0035] FIG. 5 is a perspective view of part of a pouring device with adjusting means arranged on the slot plates.

[0036] FIG. 1 shows a schematic view of an installation for operating a method which serves to produce composite elements 1. The installation comprises a double belt conveying installation 21 into which two facing layers 11 are fed. A lower facing layer 11 is uncoiled from a facing layer roller 20 and an upper facing layer 11 is likewise uncoiled from a further facing layer roller 20. The two facing layers 11 are introduced into the conveying installation 21 with a gap between them, and a reaction mixture 10 is applied to the inner surface of the lower facing layer 11 with a pouring device 100. The pouring device 100 adjoins a mixing head 19 via a feed port 12, and in the mixing head 19, represented by two arrows, at least the components polyol and isocyanate are input in an appropriate mixing ratio, wherein air loading of the reaction mixture 10 may possibly be provided, this not being shown merely for the purpose of simplification.

[0037] The pouring device 100 is positioned spaced from the double belt conveying installation 21 in such a way that the reaction mixture foams over a foaming distance such that the bottom of the upper facing layer 11 is reached by the foaming and, on passage of the composite element 1 formed in this way through the double belt conveying installation 21, the polyurethane foam core between the two facing layers 11 may cure. After passage through the double belt conveying installation 21, the endless material of the composite element 1 may be separated to form individual sandwich panels, in a manner not shown in any greater detail.

[0038] FIG. 2 shows an example of a slot plate 14, wherein the perspective representation is selected such that the slot space 15 is visible, wherein the counter slot plate has been removed in order to reveal the shallow slot space 15. The slot plate 14 shown comprises openings 23 for receiving fastening means, such that two slot plates 14 may be brought together in order to form the pouring device 100 and in order thereby to complete the slot space 15.

[0039] Shown by way of example is a feed port 12 for supplying reaction mixture 10, and the feed port 12 is connected for flow with a feed duct 16, which is introduced into the slot plate 14. Downstream of an intermediate duct 24 for connection to the feed port 12, the feed duct 16 branches off to both sides of a transverse direction Q, such that the feed duct 16 has two branches, which extend sideways away from the feed port 12.

[0040] Thus, a symmetrical configuration of the pouring device is shown merely by way of example which may alternatively also be formed asymmetrically on just one side of the feed port 12, such that just one branch of the feed duct 16 adjoins the feed port 12.

[0041] The lower edge of the slot plate 14 forms an outlet slot 13 together with the further slot plate 14, which is not shown. The outlet slot 13 extends lengthwise over the transverse direction Q between the two ends of the feed duct 16, and the feed duct 16 is curved in such a way that it approaches the edge of the outlet slot 13 as the distance from the feed port 12 increases and finally terminates therewith at the end. Thus, the greater is the distance from the feed port 12, the smaller the height of the slot space 15 becomes in the vertical direction H. The feed duct 16 itself is introduced as a groove-like recess in the slot plate 14 and has a duct cross-section 17 which tapers as the distance from the feed port 12 increases.

[0042] The changing duct cross-section 17, the curvature in the feed duct 16 and thus the changing height in the vertical direction H of the slot space 15 are matched to one another in such a way that the reaction mixture 10 experiences the same transit time through the pouring device 100 over the entire length of the outlet slot 13, and the discharge rate of the reaction mixture 10 out of the outlet slot 13 is likewise the same over the length of the entire outlet slot 13.

[0043] FIG. 3 shows a cross-sectional view through the pouring device 100 with cross-sectioned slot plates 14. In this case, a slot space 15 is visible, which extends between the two slot plates 14 and extends in the vertical direction H from the feed duct 16 to the bottom outlet slot 13. The slot space 15 has a constant width B over its two-dimensional extent, and the two-dimensional extent arises between the feed duct 16 and the outlet slot 13 in the vertical direction H and the transverse direction Q, to which the vertical direction H is perpendicular.

[0044] FIG. 3a shows a modified embodiment of the outlet slot 13 with slot lips 26 formed thereon, wherein the slot lips 26 project beyond the plate end of the slot plates 14 and form thin lip-like projections. This prevents reaction mixture from being able to accumulate in the outer region of the outlet slot 13, a situation which could interfere with discharge of the reaction mixture at the outer surface of the slot plates 14 if relatively large quantities were to accumulate.

[0045] FIG. 4 shows two individual pouring devices 100 arranged next to one another, these being arranged next to one another in such a way in the transverse direction Q that a single continuous outlet slot 13 arises. If the respective feed ports 12 are fed with reaction mixture 10, the reaction mixture 10 passes with the above-described advantages through the respective feed ducts 16 of the pouring devices 100 and exits via the common outlet slot 13 over twice the outlet length. The common outlet slot 13 extends in the same transverse direction Q for both pouring devices 100. Overall, it thus results in an increased linear width for application of the reaction mixture 10 in the case of individual slot spaces 15 of relatively small configuration, and for a width of the facing layer 11, for example with a width of 120 cm, it is not necessary to provide a single slot plate 14 with a continuous slot space 15 but rather multiple individual slot spaces 15 may be formed below associated feed ducts 16.

[0046] Finally, FIG. 5 further shows a perspective view of a part of the pouring device 100 with two slot plates 14 applied against one another and a slot space 15 formed between the slot plates 14. In order to adjust the outlet slot 13 with regard to the width B, a plurality of adjusting means 18 are arranged distributed in the transverse direction Q over the length of the outlet slot 13, which adjusting means may adjust an associated portion of the outlet slot 13 with regard to the width B via actuators 22. Through appropriate adjustment of the adjusting means 18 via the actuators 22, for example with an associated tool, the outlet slot 13 may be adjusted in regard to its width B such that the application uniformity of the reaction mixture 10 may be further improved. Associated dial gauges 25 in this case allow monitoring of the width B associated with the respective adjusting means 18.

[0047] The invention is not limited in embodiment to the above-stated preferred exemplary embodiments. Rather, a number of variants are conceivable which make use of the solution described even in the case of fundamentally different embodiments. All the features and/or advantages resulting from the claims, description or drawings, including structural details or spatial arrangements, may be essential to the invention both per se and in the most varied combinations.

LIST OF REFERENCE NUMERALS

[0048] 100 Pouring device [0049] 1 Composite element [0050] 10 Reaction mixture [0051] 11 Facing layer [0052] 12 Feed port [0053] 13 Outlet slot [0054] 14 Slot plate [0055] 15 Slot space [0056] 16 Feed duct [0057] 17 Duct cross-section [0058] 18 Adjusting means [0059] 19 Mixing head [0060] 20 Facing layer roller [0061] 21 Double belt conveying installation [0062] 22 Actuators [0063] 23 Opening [0064] 24 Intermediate duct [0065] 25 Dial gauge [0066] 26 Slot lip [0067] Q Transverse direction [0068] H Vertical direction [0069] B Width