Slotted nozzle

Abstract

A slotted nozzle for discharging a liquid adhesive to a narrow edge of a substrate includes a nozzle body, a nozzle slot formed in the nozzle body, a passage in the nozzle body for supplying the adhesive to the nozzle slot, and a slot-shaped outlet opening of the nozzle slot. The nozzle body is configured in the region of averted ends of the nozzle slot that are based on the longitudinal extent of the nozzle slot in such a manner that an increased outlet of the adhesive through the outlet opening takes place in the region of the averted ends of the nozzle slot.

Claims

1. A slotted nozzle for discharging a liquid adhesive to a narrow edge of a substrate, comprising: a nozzle body; a nozzle slot formed in the nozzle body; a passage in the nozzle body for supplying the adhesive to the nozzle slot; and a slot-shaped outlet opening of the nozzle slot; wherein the nozzle body is configured with averted ends of the nozzle slot that are based on the longitudinal extent of the nozzle slot in such a manner that an increased outlet of the adhesive through the outlet opening takes place in a region of the averted ends of the nozzle slot.

2. The slotted nozzle as claimed in claim 1, wherein the nozzle body forms closing edges in the region of the averted ends of the nozzle slot.

3. The slotted nozzle as claimed in claim 2, wherein, as a result of a reduction in a flow cross section of the nozzle body toward the outlet opening, which has a constant width, an increased outlet of the adhesive through the outlet opening in the region of the averted ends of the nozzle slot is produced.

4. The slotted nozzle as claimed in claim 3, wherein the nozzle body is configured in the region of the averted ends of the nozzle slot in such a manner that the flow cross section of the nozzle body is continuously reduced toward the outlet opening.

5. The slotted nozzle as claimed in claim 2, wherein the closing edges each have a non-linear shape.

6. The slotted nozzle as claimed in claim 5, wherein the closing edges have an identical shape arranged in a mirror-inverted manner.

7. The slotted nozzle as claimed in claim 2, wherein the outlet opening has a greater width extent in the region of the averted ends of the nozzle slot than in a remaining region of the outlet opening, which remaining region of the outlet opening has a constant width.

8. The slotted nozzle as claimed in claim 7, wherein the nozzle body has an expansion of the outlet opening in a region of the closing edges, the width of the outlet opening otherwise being constant.

9. The slotted nozzle as claimed in claim 2, wherein the nozzle body tapers toward the outlet opening in one of the region of the averted ends of the nozzle slot, and the outlet opening has a greater width in comparison to the outlet opening which has an otherwise constant width in the other region of the averted ends of the nozzle slot.

10. The slotted nozzle as claimed in claim 9, wherein the closing edges define a pair of closing edges and one of the pair of closing edges has a curved shape, and wherein the nozzle body has an expansion of the outlet opening in a region of the other closing edge, with the width of the outlet opening otherwise being constant.

11. The slotted nozzle as claimed in claim 1, wherein a length of the nozzle slot and the outlet opening is adjustable.

12. The slotted nozzle as claimed in claim 11, wherein the nozzle body has a basic body and an adjustment part, and wherein a length of the nozzle slot and the outlet opening is adjustable by the adjustment part which is mounted displaceably in the basic body and passes through the nozzle slot.

13. The slotted nozzle as claimed in claim 12, wherein a rod that is mounted displaceably in the basic body and is adjustable accommodates the adjustment part in a region of a free end of a plate-like tab.

14. The slotted nozzle as claimed in claim 12, wherein the adjustment part has a closing edge on a side of the adjustment part facing a region of the nozzle slot which receives the adhesive.

15. A slotted nozzle for discharging an adhesive, comprising: a nozzle body; a nozzle slot formed in the nozzle body; a passage in the nozzle body for supplying the adhesive to the nozzle slot; and an outlet opening of the nozzle slot; wherein the nozzle slot of the nozzle body has ends of a length of the nozzle slot that are configured such that an increased outlet of the adhesive through the outlet opening takes place at the ends of the nozzle slot; and wherein the outlet opening has a greater width at the ends of the nozzle slot than at an inner length of the outlet opening.

16. A slotted nozzle for discharging an adhesive, comprising: a nozzle body; a nozzle slot formed in the nozzle body; a passage in the nozzle body for supplying the adhesive to the nozzle slot; and an outlet opening of the nozzle slot; wherein the nozzle slot of the nozzle body has ends of a length of the nozzle slot that are configured such that an increased outlet of the adhesive through the outlet opening takes place at the ends of the nozzle slot; and wherein the nozzle body tapers toward the outlet opening at one of the ends of the nozzle slot, and the outlet opening has a greater width at the other end of the nozzle slot in comparison to an inner length of the outlet opening that is constant.

Description

BRIEF DESCRIPTION OF THE DRAWING FIGURES

(1) In the accompanying drawing figures, the invention is illustrated with reference to exemplary embodiments without being restricted to said exemplary embodiments.

(2) FIG. 1 shows the prior art, namely a section through a nozzle part of an adjustable slotted nozzle for discharging liquid adhesive according to the line I-I in FIG. 3, with a plunger rod and a tab for adjusting an outlet opening of the slotted nozzle.

(3) FIG. 2 shows the prior art, namely relating to FIG. 1, in a side view of the disassembled plunger rod with tab.

(4) FIG. 3 shows the prior art, namely a section through the slotted nozzle according to the line III-III in FIG. 1.

(5) FIG. 4 shows an application of adhesive applied to a substrate by means of the slotted nozzle with respect to the prior art in FIGS. 1-3.

(6) FIG. 5 shows an application of adhesive applied to a substrate by means of the slotted nozzle, with respect to the prior art in FIGS. 1-3, after the fitting and pressing of an edge band.

(7) FIGS. 6 and 7 show illustrations which correspond to the illustrations in FIGS. 4 and 5, but during application of an adhesive to the substrate by means of a slotted nozzle configured according to the invention.

(8) FIG. 8 shows, for a first exemplary embodiment of the slotted nozzle according to the invention, a section through the nozzle part of the adjustable slotted nozzle according to the line VIII-VIII in FIG. 9, corresponding to the sectional illustration with respect to the prior art according to FIG. 1.

(9) FIG. 9 shows a section through the slotted nozzle according to the line IX-IX in FIG. 8, corresponding to the sectional illustration with respect to the prior art in FIG. 3.

(10) FIG. 10 shows a second exemplary embodiment of the slotted nozzle according to the invention in a sectional illustration according to the line VIII-VIII in FIG. 9.

(11) FIG. 11 shows a detailed view according to the arrow XI in FIG. 10.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS OF THE INVENTION

(12) FIGS. 1 to 3 show a nozzle part of a slotted nozzle 1 according to the prior art. The slotted nozzle 1 serves for discharging liquid adhesive. The slotted nozzle 1 has a nozzle body 2, a nozzle slot 3 formed in the nozzle body 2, a passage 4 in the nozzle body 2 for supplying the adhesive to the nozzle slot 3, and a slot-shaped outlet opening 5 of the nozzle slot 3. Averted ends of the nozzle slot 3 are indicated by the reference signs 6 and 7. The length of the nozzle slot 3 and the length of the outlet opening 5 is indicated by the dimension l, and the width in each case by the dimension b.

(13) The length l of the nozzle slot is adjustable. Adhesive can emerge from the slotted nozzle 1 through the nozzle slot 3 and the outlet opening 5. The outlet opening 5 is rectangular. By adjustment of the slotted nozzle 1, the length extent of nozzle slot 3 and outlet opening 5 can be changed, while the width extent of nozzle slot 3 and outlet opening 5 is unchanged.

(14) A first nozzle part 8 and a second nozzle part 9 of the nozzle body 2 are held together by a fastening body 10 by means of adjusting screws 11. A bore 12 is provided centrally through the two nozzle parts 8, 9 somewhat below the outlet opening 5 of the slotted nozzle 1. Located in said bore is a plunger rod 13 with a tab 14 which is fastened thereto and projects into the nozzle slot 3 between the bore 12 and the outlet opening 5. A plunger seal 15 is located on the plunger rod 13, said plunger seal separating that space of the bore 12 and of the nozzle slot 3 which is fillable with adhesive from that space of the bore 12 and of the nozzle slot 3 which is not fillable with adhesive. Adhesive can be conveyed through the passage 4, which is designed as a further bore, into the bore 12 and the nozzle slot 3 and can then emerge at the outlet opening 5 of the slotted nozzle 1. The length of the nozzle slot 3 and of the outlet opening 5 can be changed by displacement of the plunger rod 13 with the tab 14 in the direction of the longitudinal extent of the bore 12.

(15) With a slotted nozzle 1 according to this prior art, an application 16 of adhesive to an edge of the substrate 17, as illustrated in FIG. 4, can be produced with the apparatus for fitting an edge band in an edge bander. In the application of adhesive, which is indicated somewhat thicker than the thickness customary in practice for better visibility, the increase 18 and decrease 19 of the application 16 of adhesive at the edges of the substrate 17 is readily visible. If the edge band 20 is fitted, the pressing power against the edge band 20 is not capable of deforming the application of adhesive, and an annoying visible gap arises at the two substrate corner edges, as illustrated in FIG. 5.

(16) The invention presents a slotted nozzle 1 with which it is possible to slightly over-increase the application 16 of adhesive to the substrate 17 by way of the increase 18 and the decrease 19, as illustrated in FIG. 6. If the edge band 20 is applied and pressed on, the boosting of the adhesive by way of the increase 18 and at the decrease 19 of the application 16 of adhesive is deformed and fills the region of increase and decrease with adhesive. This is shown in FIG. 7. The annoying visible gap is no longer present. In this embodiment, the application of adhesive can be deformed because the over-increase in adhesive is only partially applied and, when the edge band is pressed on, the entire pressing force acts on the two over-increases in adhesive. Since adhesive is uncompressible, the adhesive is displaced toward the corners of the application of the adhesive.

(17) FIGS. 8 and 9 illustrate a first exemplary embodiment of the invention. The illustration of FIG. 9 corresponds here to that of FIG. 3. With regard to the basic construction of the slotted nozzle 1, reference is made to the above explanations regarding the slotted nozzle 1 according to the prior art in order to avoid repetitions. The nozzle body 2 according to the invention differs from that according to the prior art only by means of the special design of the tab 14 in the region of the end-side edge thereof facing the nozzle slot 3, i.e. the closing edge 21, and the end-side edge opposite the latter and therefore arranged on the other side of the nozzle slot 3, i.e. the closing edge 22, which closing edges are formed by the two nozzle parts 8, 9.

(18) In FIGS. 8 and 9, in particular FIG. 8, the passage 4 and the bore 12, the plunger rod 13 with the tab 14, and the outlet opening 5 with the length l are visible. That end of the tab 14 which points toward the nozzle slot 3 and the outlet opening 5, i.e. the closing edge 21, has a curved shape. The closing edge 22 which is incorporated into the first and second nozzle parts 8, 9 and is opposite the end of tab 14 with the curved shape, i.e. the closing edge 21, likewise has a curved shape which is formed in a mirror-inverted manner with respect to the curved shape of the closing edge 21. The adhesive passes via the passage 4 into the bore 12 and flows from there through the nozzle slot 3, which is bounded between the closing edges 21, 22, toward the outlet opening 5 with the length l. By means of the flow cross section which becomes increasingly smaller from the bore 12 as far as the outlet opening 5, an increased emergence of adhesive arises at the two ends 6, 7 of the outlet opening 5. Said increased emergence of adhesive has the result that, with a slotted nozzle 1, used in the apparatus for gluing edges of a substrate on edge banders, the application of adhesive described above with respect to FIG. 6 with the over-increases 18, 19 in the adhesive can be realized.

(19) In a second embodiment of the invention, which is illustrated in FIGS. 10 and 11, the tab 14 is designed with the closing edge 21 thereof in accordance with the first exemplary embodiment of the invention, and therefore has the curved shape. However, the other closing edge 22 is modified. It does not have a curved shape within the meaning of the curved shape of the closing edge 21, but rather the outlet opening 5 has a slightly greater width b1 in the region of the end 7 in comparison to the otherwise constant width b of the outlet opening. An increased emergence of the adhesive through the outlet opening 5 can therefore also take place in the region of this end 7. In this exemplary embodiment of the slotted nozzle 1, the closing edge 22 for the nozzle slot 3, through which adhesive can flow and which is incorporated in the first and/or the second nozzle part 8, 9 and which is opposite the tab 14, is a rectilinear groove 23 with an extent s toward the nozzle slot 3, thus resulting in the greater width b1 of the outlet opening 5. Said groove 23 can extend over the entire length of the closing edge 22. In principle, however, it is sufficient if the groove 23 is arranged in that region of the closing edge 22 which is adjacent to the outlet opening 5. The depth of the groove 23 is small here and is only a few percent of the width b of nozzle slot 3 and outlet opening 5, which width approximately corresponds to the thickness of the tab 14.

(20) The rectilinear groove 23 does not have to be arranged at right angles to the bore 12, as depicted, but rather may also be formed inclined toward the nozzle slot 3 or the outlet opening 5. With a slotted nozzle 1 which has a tab 14 of curved shape and such a groove 23, which bound the slot of the outlet opening 5 having the length l, the increased ejection of adhesive at the ends 6, 7 of the outlet opening 5 can likewise be achieved. For the gluing of the edges of a substrate in edge banders, the above-described effect can also be realized with this solution. In particular, if the slotted nozzle 1 is not adjustable and accordingly a movable tab 14 is not required, the nozzle body can be designed in such a manner that it then has a groove in the region of the closing edge 21 of the nozzle body 2, the groove of the closing edge 21 being designed in accordance with the groove 23.