Two-component drip edge

Abstract

The invention relates to a device having a two-component drip edge. One side of the drip edge is formed by a material having an attractive behavior with respect to a liquid and the opposite side of the drip edge is formed from a material having a repulsive behavior with respect to the liquid. This design yields an improved drip effect.

Claims

1. A device for controlled diversion of liquids from a surface that can be wetted with a liquid, comprising the surface that can be wetted with liquid and a two-component drip edge attached to the surface, the two-component drip edge formed by an edge aligned in the direction of gravitational force and a first flank and a second flank meeting in and leading away from the edge, characterized in that the first flank is connected to the surface that can be wetted with liquid and has a higher surface tension than the second flank.

2. The device according to claim 1, wherein the first flank is made of iron, polyamide, polyethylene terephthalate, polymethyl methacrylate, polyethylene, polyvinyl chloride, polyoxymethylene, polystyrene or steel.

3. The device according to claim 1, wherein the second flank is made of polypropylene, paraffin wax, epoxy resin or polytetrafluoroethylene.

4. The device according to claim 1, wherein the first flank is made of steel and the second flank is made of polytetrafluoroethylene.

5. The device according to claim 1, wherein the first flank and the second flank meet in the edge to form an angle between 20° and 120°.

6. The device according to claim 1, characterized in that the two-component drip edge has a height of 4-8 mm.

7. The device according to claim 1, characterized in that the two-component drip edge has a height of 5 mm.

8. A device for controlled diversion of liquids from a rotationally symmetrical surface that can be wetted with liquid, comprising the rotationally symmetrical surface and a two-component drip edge connected to the rotationally symmetrical surface and formed by an edge, which edge is disposed concentrically with the rotationally symmetrical surface and is directed outward, and a first flank and a second flank meeting in and leading away from the edge, wherein the first flank is connected to the surface that can be wetted with liquid and has a higher surface tension than the second flank.

9. The device according to claim 8, characterized in that the surface is designed in the form of a cylinder.

10. A pan roller for transferring a liquid, comprising a transfer cylinder having two connecting pieces for fastening the pan roller in bearings, characterized in that the connecting pieces each have a surface wetted with liquid during use and at least one two-component drip edge for controlled dripping of the liquid to be transferred, wherein the at least one two-component drip edge is formed by an edge, which edge is disposed concentrically with the transfer cylinder and is directed outward, and a first flank and a second flank meeting in and leading away from the edge, wherein the first flank is connected to the surface that can be wetted with liquid and has a higher surface tension than the second flank, and wherein the second flank faces the bearing and the first flank faces the transfer cylinder.

11. The pan roller according to claim 10, characterized in that at least one single component pre-drip edge is disposed between the two-component drip edge and the transfer cylinder.

12. The pan roller according to claim 11, characterized in that the at least one single component pre-drip edge has a height of 4-8 mm.

13. The pan roller according to claim 11, characterized in that the at least one single component pre-drip edge has a height of 5 mm.

14. The pan roller according to claim 11, characterized in that the at least one single component pre-drip edge has two flanks forming an angle of 20-80°.

15. A printing machine having at least one pan roller according to claim 10.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 shows a schematic diagram of a first embodiment of the drip edge according to the disclosure.

(2) FIG. 2 shows a schematic diagram of a second embodiment of a drip edge disposed in a circular pattern around a cylinder.

(3) FIG. 3 shows a schematic diagram of a roller according to the disclosure.

(4) FIG. 4 shows schematically the use of a roller according to the disclosure in a printing machine.

DETAILED DESCRIPTION OF AN EXEMPLARY EMBODIMENT

(5) FIG. 1 shows schematically the structure of the device having a two-component drip edge, which is mounted on the underside of a surface (17) aligned at a right angle to the gravitational force. The two-component drip edge is formed by a first flank (19) and a second flank (20), which meet in the edge (18), which is aligned in the direction of the gravitational force. The first flank (19) is disposed on the side of the surface, which is wetted with liquid (5). The first flank (19) is made of a material having approximately the same surface tension as the wetting liquid (5) or having a greater surface tension than the liquid (5). The second flank (20) is formed by a material having a lower surface tension than the material of which the first flank (19) is formed. The surface tension of the material used for the second flank (20) is advantageously lower than the surface tension of the liquid with which the device comes in contact. The liquid (5) spreads on the surface (17) and the first flank (19). As soon as the liquid front has reached the edge (18), a drop forms due to the reversal of the direction of the surface opposite the direction of the gravitational force and also due to the repulsive behavior of the second flank (20) with respect to the liquid dripping off the edge of the drip edge of the surface.

(6) FIG. 2 shows schematically a longitudinal section through a device for controlled diversion of liquids with a rotationally symmetrical surface in the form of a cylinder (1). A two-component drip edge formed by an edge designed to be concentric with the surface and directed outward and having a first flank and a second flank leading away from the edge is disposed on the surface, which is designed in the form of a cylinder, wherein the first flank is connected to the liquid-wettable surface and has a higher surface tension than the second flank. The two flanks are each in the form of a truncated cone. In the embodiment shown here, the second flank (4) is secured by the clamping ring (10).

(7) FIG. 3 shows a roller according to the disclosure, such as that which can be used as a pan roller in a printing machine, for example. The transfer cylinder, which is immersed into the ink during operation, has a connecting part (7) on each end. The pan roller is rotated at a rotational speed of 15 revolutions per minute, for example, during operation. The ink then not only wets the jacket of the cylinder but also migrates onto the surface of the connecting parts (7) during operation. Starting from the transfer cylinder in the direction of the end of the connecting part, a first and a second single-component drip edge (8, 9) are initially disposed advantageously on the connecting part. These may be formed from the material of the connecting part itself, for example, they may be made of steel or iron. These single-component drip edges (8, 9) have a height of 5 mm and, at the surface of the connecting part, a width of approximately 4 mm. To improve the drip behavior, the angle should be selected to be as acute as possible; to avoid cut injuries in cleaning, a minimal angle is advisable. The angle formed by the two flanks of the pre-drip edge may be 40°, for example. Since the roller rotates during operation, complete blockage of the liquid or, when using the roller in a printing machine, complete blockage of the ink with respect to the bearings, is not ensured. For this reason, a two-component drip edge according to the invention is disposed downstream from these single-component pre-drip edges.

(8) The first flank of the drip edge is formed from the material of the connecting part (7), namely steel in this case. The two flanks of the two-component drip edge in this case form an angle of 97°, with the first flank (3) advantageously being designed to be shallower than the second flank (4) in relation to the axis of the connecting part. The second flank (4) consists of a Teflon® (polytetrafluoroethylene) ring mounted directly on the first flank (3) and secured by the clamping ring (10). The roller may be installed in a printing machine, for example, with the bearings (11).

(9) FIG. 4 shows schematically the use of the roller according to the disclosure in a printing machine in conjunction with the pan roller (15) described in relation to FIG. 3. Individual elements of the diagram in FIG. 3 have been omitted with regard to a clearer illustration. The pan roller (15) is partially immersed in an immersion bath (14), from which it picks up the ink and transfers it to the printing roller (13).

(10) The pan roller (15) is secured in the printing machine (16) by means of the connecting parts (7) and bearings (11) and connected to the rotary motor (12). Due to the disposition of the drip edges, the ink drips off above the immersion bath and cannot leak into the bearings and the motor. A printing machine according to the invention therefore requires less maintenance.

LIST OF REFERENCE NUMERALS

(11) cyclinder surface (1) edge (2) first flank (3) second flank (4) liquid (5) transfer cylinder (6) connecting parts (7) single-component pre-drip edge (8) single-component pre-drip edge (9) clamping ring (10) bearing (11) rotary motor (12) printing roller (13) immersion bath (14) pan roller (15) printing machine (16) wettable surface (17) edge (18) first flank (19) second flank (20)