FUNNEL NOSE AND FORMER

Description

[0001] The invention relates to a former nose for a folding former for folding a web-shaped or sheet-shaped substrate running in the transport direction X, comprising a cover surface with two cover surface edges tapering to a point in the transport direction X, over which the substrate is transported in the region of a fold to be formed, and a curved leg surface adjacent to each of the cover surface edges, wherein at least one blow air duct for the outflow of blow air supplied under pressure emerges from each leg surface, wherein the blow air duct has an exit surface on the respective leg surface, wherein at least one exit surface has a first extension a and a second extension b, wherein the first extension a is greater than the second extension b.

[0002] Furthermore, the present invention relates to a former with a former nose according to the invention and to a method for producing a former nose according to the invention.

[0003] Formers are known from the prior art, for example, as used on web-fed printing presses for producing newspapers or commercial products. Formers are also used in post-press systems outside of printing presses, where a printed or unprinted substrate is provided with a fold in the transport direction.

[0004] Such a former is typically triangular in shape, generally comprising a former plate, to which the rounded former legs are attached at the sides. A former is usually aligned at an obtuse angle to the direction of the incoming substrate, so that the substrate to be folded is deflected by the former for transport.

[0005] The surfaces on both sides of the future longitudinal fold are guided over the funnel legs so that a fold is formed at the tip of the funnel in the transport direction, which is why this is also called a longitudinal fold.

[0006] Since this funnel tip is intended to produce a precise longitudinal fold, correspondingly high demands are placed on it in order to be able to form a clean longitudinal fold in different materials, especially since the funnel tip must have a high level of wear resistance due to the unavoidable contact with the substrate to be folded in this area.

[0007] For this reason, conventional formers use so-called former noses as former tips. These are manufactured as a separate component and reversibly mounted on the former. This makes it possible to adapt the geometry of the former tip to different materials being folded by replacing the former nose. Furthermore, if the former tip becomes worn, only the former nose can be replaced without having to replace the entire former.

[0008] Such former noses essentially have a similar geometry to the formers, i.e., they comprise a substantially triangular cover surface with two cover surface edges tapering to a point in the transport direction X of the substrate to be folded, over which the substrate is transported in the region of a fold to be formed, as well as a curved leg surface adjacent to each of the cover surface edges. Only the design of the tip varies depending on the substrate to be folded, but these are not relevant to the present invention.

[0009] To avoid friction and thus also wear, the curved leg surfaces have a very smooth surface, partly a special friction-reducing coating and outlets for the discharge of blown air, which forms an air cushion between the substrate to be folded and the funnel nose.

[0010] Different designs are known for the funnel tips or funnel noses known from the prior art.

[0011] For example, DE 44 35 528 A1 teaches that the cover surface should be designed as a separately mounted sheet metal, so that air escapes from a gap between the cover surface designed as a sheet metal part and the leg surfaces in the area of ​​the cover surface.

[0012] EP 0 945 385 A2 teaches that the blowing air is supplied via long slots in the area of ​​the cover surface parallel to the cover surface edges.

[0013] However, such designs have the disadvantage that due to the deflection of the substrate at the funnel legs and leg surfaces, the blowing air cannot reach a sufficient extent in the area of ​​the funnel legs and leg surfaces between the funnel legs or leg surfaces and the substrate, which leads to problems with depositing of printed substrates to be folded and / or to increased wear of these surfaces and / or to web tension problems.

[0014] DE 100 31 814 A1 teaches the installation of holes in the area of ​​the funnel legs through which the blowing air can escape. However, holes with a diameter that is too small become clogged after a relatively short time with incompletely cured printing ink, coatings on the substrate to be folded, such as silicone, or paper dust, and in this case can no longer supply sufficient blowing air.

[0015] US 5,779,616 discloses a former and a former nose which has tapered curved leg surfaces, and wherein the plane facing the paper web between the leg surfaces is filled with a flat cover plate which is set back from the paper web to be folded, and wherein openings for supplying blown air are provided in this flat cover plate.

[0016] US 4,321,051 discloses a former, wherein the former is constructed from two mutually symmetrical sheet metal parts, wherein the outer sheet metal edges are bent with a variable radius to form the curved leg surfaces, and wherein openings for the discharge of blown air are provided in the region of the curved leg surfaces.

[0017] DE 1 142 878 discloses a former with two external curved leg surfaces, with blow air openings arranged along the former edges.

[0018] Holes with a larger diameter, i.e. with a diameter in the range of a few to several millimeters, are less susceptible to this, but can only blow the blowing air in at specific points, since there must be a relatively large distance between the holes in order to maintain the curved contour of the leg surfaces.

[0019] The invention is therefore based on the object of creating a solution with which blowing air can be supplied to the area of ​​the leg surfaces in sufficient quantity and reliably without significantly impairing the contour of the leg surfaces.

[0020] This object is achieved by a former nose according to claim 1 or a former according to claim 12. Not exclusively, but advantageously, this can be realized with a method according to claim 13.

[0021] The funnel nose according to the invention is characterized in that the first extension a encloses an angle of 15° to 75° to the adjacent cover surface edge.

[0022] This geometry allows for minimal disruption to the contour of the leg surface, particularly in the transport direction of the substrate to be folded. This is why the exit surfaces can be arranged at a relatively short distance from one another on a leg surface. This angular offset allows for smooth gliding of the substrate due to the only localized disruption to a cross-section of the leg surface perpendicular to the transport direction. This is particularly advantageous when folding curved substrates. This allows for the supply of high blast air volumes, which, combined with only short distances to the adjacent exit surface, leads to low friction between the substrate to be folded and the funnel nose, resulting in high product quality of the substrate to be folded and low wear.

[0023] Such geometries were and are very difficult to produce, if at all, using conventional manufacturing methods, which is why an additive manufacturing process, also known as a 3D printing process, is preferred for producing a funnel nose according to the invention according to claim 13.

[0024] According to a further embodiment of the invention, the first extension a encloses an angle of 30° to 60° to the adjacent cover surface edge.

[0025] According to a further embodiment of the invention, the dimension of the second extension b lies in a range of 0.5 to 5 millimeters, in particular in a range of 0.8 to 1.5 millimeters. An exit surface with this smallest dimension is less prone to clogging with printing ink and / or paper dust, can still be easily cleaned if necessary, and furthermore allows the supply of a high volume of blowing air without compromising the geometry of a leg surface required for guiding the substrate.

[0026] According to a further embodiment of the invention, the ratio of the first extension a to the second extension b is in a range from 1.5 to 15, in particular in a range from 2 to 10. Such outlet surfaces have a substantially slot-shaped, elliptical, or S-shaped configuration and thus enable the discharge of large quantities of blast air, not only at specific points but over large areas of the leg surface, which is subject to high frictional stress. Preferred developments of the invention are evident from the subclaims and the following description.

[0027] Various embodiments of the invention are explained in more detail with reference to the drawings, without being limited thereto. Fig. 1 a former known from the prior art with a former nose Fig. 2 an exemplary embodiment of a former nose according to the invention in three-dimensional view Fig. 3 a detailed view of an exemplary exit surface located on the leg surface Fig. 4 a detailed view of an exemplary embodiment of an exit surface located on the leg surface Fig. 5 a detailed view of an exemplary embodiment of an exit surface located on the leg surface Fig. 6 a detailed view of an exemplary embodiment of an exit surface with a web located on the leg surface Fig. 7 a cross section through an exemplary blowing air duct Fig. 8 a cross section through an exemplary blowing air duct

[0028] Fig. 1shows a former 10 as is known from the prior art. Such a former 10 comprises a former plate 11, which is also referred to as a former plate. This former plate 11 is essentially triangular in shape, in particular an isosceles triangle, especially when the former plate 11 also forms the tapered former tip 7. Attached to the two sides of the triangular former plate 11 are the so-called former legs 12, which have a curved, in particular cylindrical or conical, curvature.

[0029] These funnel legs 12 can be designed in the form of a bent sheet metal; in the simplest case, these are the correspondingly bent edge areas of the funnel plate 11. However, the funnel legs 12 are often also made of round material such as pipes or conically machined pipes to which the funnel plate 11 is attached.

[0030] Such a former 10 serves to fold a substrate that runs over the former 10 in the transport direction X, which substrate is generally both sheet-shaped and, in particular, web-shaped. The substrate (not shown) guided over the former 10 in the transport direction X encloses the former legs 12, so that a fold is formed in the transport direction X by the former tip 7.

[0031] Since the former tip 7 is subject to high demands in terms of geometry and since the former tip 7 is subject to relatively heavy wear, formers 10 often comprise a former nose 1, which is manufactured as a separate component and is attached to the former 10 by means of a detachable and thus reversible connection.

[0032] This allows the funnel nose 1 to be made of a different material than the funnel sheet 11, the funnel tip 7 to be designed with a geometry adapted to the substrate, and only the funnel tip 7 to be replaced in the event of excessive wear.

[0033] Fig. 2 shows such a funnel nose 1 in three-dimensional representation. Fig. 2 The geometry of the funnel nose 1 shown is purely exemplary, since in particular the funnel tip 7 is designed depending on the substrate.

[0034] The funnel nose 1 comprises a cover surface 2 with two cover surface edges 3 which taper to a point in the transport direction X and over which the substrate is transported in the region of a fold to be formed, as well as a curved leg surface 4 adjacent to each of the cover surface edges 3, wherein at least one blow air channel 5 for the outflow of blow air supplied under pressure emerges from each leg surface 4, wherein the blow air channel 5 has an outlet surface 6 on the respective leg surface 4. According to the invention, at least one outlet surface 6 has a first extension a and a second extension b, wherein the first extension a is greater than the second extension b.

[0035] At the Fig. 2In the exemplary embodiment of the funnel nose 1 shown, five blow air channels 5 with an outlet surface 6 are shown on the curved leg surface 4, whereby this number is merely exemplary. The number of blow air channels 5 for the outflow of blow air can be chosen arbitrarily and depends in particular on the angle α enclosed with the cover surface edge 3 and the length ratio, i.e., the ratio of the first extension a to the second extension b.

[0036] Although in Fig. 2 only the leg surface 4 arranged on the right side as seen in the transport direction X is shown, it is mentioned here for the sake of completeness that the leg surface 4 arranged on the left side as seen in the transport direction X also has at least one blowing air channel 5 with an outlet surface 6 which is projected on the leg surface 4.

[0037] In a preferred embodiment, the funnel nose 1 is symmetrical to a plane (not shown) running through the funnel tip 7 and arranged perpendicular to the cover surface 2.

[0038] The blowing air channels 5 thus have essentially the shape of a slot due to the ratio of the first extension a to the second extension b.

[0039] The Figures 3 , 4 and 5 show different designs of the exit surfaces 6 of the section Y resulting from the blow air channels 5 on the leg surfaces 4 of the Fig. 2 on an enlarged scale.

[0040] Fig. 3shows a rectangular outlet surface 6 of the blown air duct 5 on the leg surface 4, designed as an example as a developed section of the leg surface 4, which has a first extension a and a second extension b. The first extension a is larger than the second extension b, so that the blown air duct 5 has the shape of a slot, at least in the region of the leg surface 4. The corners of the outlet surface 6 can be rounded or sharp-edged.

[0041] In the example shown, the edges with the first extension a and the edges of the second extension b are each parallel. Depending on the radius of curvature of the leg surface 4, deviations from this may occur, so that the opening surface can have a parallelogram-like shape. The edge of the first extension a forms an angle α with the cover surface edge 3.

[0042] Fig. 4shows an exemplary embodiment of the outlet surface 6 of the blown air duct 5 on the leg surface 4 in an elliptical shape, which has a first maximum extension a and a second maximum extension b. The first extension a is greater than the second extension b, so that the blown air duct 5 has the shape of a slot with an elliptical cross-section, at least in the region of the leg surface 4. The first extension a forms an angle α with the cover surface edge 3.

[0043] Fig. 5shows an exemplary S-shaped outlet surface 6 of the blown air duct 5 on the leg surface 4, which has a first extension a and a second extension b. The first extension a is greater than the second extension b, so that the blown air duct 5 has the shape of an S-shaped slot, at least in the region of the leg surface 4. The corners of the outlet surface 6 can be rounded or sharp-edged. The edge of the first extension a forms an angle α with the cover surface edge 3.

[0044] The Figures 3 to 5 The embodiments shown show only a small exemplary selection of the design of the blow air channel 5 in the area of ​​the leg surface 4 covered by the invention, although all of these embodiments have the following features in common, which is why they are summarized for the Figures 3 to 5 be described.

[0045] Although not in the Figures 3 to 5As shown graphically, the angle between an edge of the first extension a and thus the first extension a can be arranged perpendicular to the adjacent cover surface edge 3. In this case, not shown graphically, the angle α is 90°.

[0046] Furthermore, the angle α between an edge of the first extension a and thus the angle α between the first extension a perpendicular and the adjacent cover surface edge 3 can be zero, so that in this case not shown in the drawing, an edge of the first extension a and / or the first extension a can be parallel to the adjacent cover surface edge 3.

[0047] According to a further embodiment, the first extension a encloses an angle α in a range of 15° to 75°, in particular in a range of 30° to 60°, with the adjacent cover surface edge 3. The angle α can be defined either in a plane spanned by the exit surface 6 or on the development of the curved leg surface 4, since the differences are extremely minor in practice.

[0048] The Figures 3 to 5 The blown air channels 5 shown with exit surfaces 6 on the leg surfaces 4 have a width and thus a second extension b that lies in a range from 0.5 millimeters to 5 millimeters. According to a further embodiment, the second extension b lies in a range from 0.8 millimeters to 1.5 millimeters.

[0049] In the case of straight or S-shaped slots, the second extension b is essentially the same over the length and thus over the first extension a, in the case of exit surfaces 6 with an essentially elliptical cross-section, as for example in Fig. 4 As shown, the largest second extension b, which is essentially perpendicular to the first extension a, is used for this purpose. Although not shown graphically, mixed forms with a curved, elliptical exit surface 6 are also possible; in such cases, the largest respective value is used for both the first extension a and the second extension.

[0050] In principle, in the case of funnel noses 1 with very large dimensions, a larger value can also be used for the second extension, but this value must not assume or exceed a value by which the shape of the curved leg surface 4 is unduly impaired in the sense of being deformed.

[0051] The exit surface 6 formed by an exit channel 5 on the leg surface 4 has a length which is defined by the ratio of the first extension a to the second extension and lies in a range from 1.5 to 15, in particular in a range from 2 to 10.

[0052] However, in order not to interrupt the contour of the curved leg surface 4 over an excessively large extent, particularly in the case of small radii of curvature, in one embodiment of the invention the outlet surface 6 has at least one web 8 over the first extent a. This web 8 projects into the blown air opening 5 and terminates on the outside with the leg surface 4. These webs 8 are preferably used with a ratio of the first extent a to the second extent b of greater than or equal to 4. An outlet surface 6 provided with a web 8 is shown by way of example in Fig. 6 The width of the web 8 is preferably in the range of 1 to 3 millimeters.

[0053] As from Fig. 2As can be seen, a plurality of blown air channels 5 and thus of outlet surfaces 6 can be arranged on a leg surface 4. If a plurality of outlet surfaces 6 are present on a leg surface 4, the outlet surfaces 6 are spaced from one another by a distance of 3 to 30 millimeters, although this distance can also be increased. However, it should be noted that a smaller distance between the outlet surfaces 6 is advantageous, as this allows a more uniform air cushion to be achieved between the substrate and the leg surface 4, as well as between the substrate and the cover surface 2.

[0054] Although in Fig. 2only the embodiment is shown in which a plurality of exit surfaces 6 are arranged in the extension of the cover surface edge 3 and are spaced apart from one another, the exit surfaces 6 can be arranged both in the extension of the cover surface edge 3 and also substantially perpendicularly and / or in the direction of the first extension a and / or in the direction of the second extension b at a corresponding distance from one another.

[0055] Regarding the exit surfaces 6, it should be noted that these can, in principle, take any round or polygonal shape, such as triangles, pentagons, or the like. However, the configuration in which the first extension a is larger than the second extension b is particularly preferred.

[0056] Even if in Fig. 2only an exemplary embodiment is shown, in which the exit surfaces 6 arranged on a leg surface 4 have the same shape, size and the same distance from one another, a plurality of exit surfaces 6 can also be arranged on one leg surface 4, which differ from one another with regard to at least one extension a or b and / or with regard to the shape of the exit surface 6 and / or with regard to the distance to the cover surface edge 3 and / or have different distances from one another.

[0057] Fig. 7 shows a schematic representation of the view of section A - A from Fig. 3. This figure shows a detail of a section through the funnel nose 1 in the area of ​​a blown air duct 5. The blown air can be fed to the at least one blown air duct 5 of a leg surface 4 via an air supply bore 9 integrated into the funnel nose 1 and flows via the air supply bore 9 into the at least one blown air duct 5. The blown air duct 5 emerges at the leg surface 4 and there forms the outlet surface 6 through which the supplied blown air can exit in order to form an air cushion between the outer surfaces of the funnel nose 1 and the substrate, not shown.

[0058] The blowing air channel 5 has, inside the funnel nose 1 and thus at a distance from the leg surface 4, a cross-sectional area or a cross-section which is larger than the area of ​​the exit surface 6 resulting on the leg surface 4. This can be achieved by the blowing air channel 5 at least partially having a substantially conical or pyramidal or truncated pyramid-shaped shape, so that the cross-section increases with increasing distance from the leg surface 4.

[0059] Such a configuration is advantageous in that, on the one hand, the leg surface 4 is only slightly interrupted by a small second extension b and, on the other hand, the larger cross section of the blown air channel 5 inside the funnel nose 1 reduces the flow velocities and can preferably be kept in the range of a laminar flow in order to thus minimize the flow losses.

[0060] Due to the Fig. 7 In the exemplary symmetrical design of the blowing air duct 5, the latter is designed such that the blowing air exiting from the outlet surface 6 exits essentially perpendicular to the leg surface 4. The same can also be achieved, for example, by designing parallel walls of the blowing air duct 5, which are essentially perpendicular to the leg surface 4.

[0061] Fig. 8 shows a further exemplary embodiment of a blowing air duct 5 in which the walls exit at an angle to the leg surface 4. Such a design can ensure that the blowing air exits at an acute angle to the leg surface 4.

[0062] It goes without saying that the walls of at least one blown air duct 5 can be designed in spatial arrangement and thus also in orientation such that both the exit angle and the exit direction can be adapted according to the geometric and flow-technical conditions so that the blown air exiting from the blown air duct 5 exits from the exit surface 6, for example, in or against the transport direction X or at any angle thereto.

[0063] To achieve high mechanical strength and high wear resistance, the funnel nose 1 is made, for example, from a nickel-based alloy, a tool steel, a martensitic steel, a ceramic material, or a combination of different materials. Additionally, it is possible to coat the funnel nose 1 with appropriate friction-reducing and / or wear-resistant coatings.

[0064] Due to the complex geometry, the funnel nose 1 is preferably manufactured using an additive manufacturing process, which is known as 3D printing, since this manufacturing process can produce almost any geometry and offers a wide variety of different materials. List of reference symbols

[0065] 1Former nose 2Cover surface 3Cover surface edge 4Leg surface 5Blow air duct 6Exit surface 7Former tip 8Web 9Air supply hole 10Former 11Former plate 12Former leg afirst extension or side extension Xtransport direction αangle

Claims

1. Former nose (1) for a former board (10) for folding a substrate running in the transport direction X, comprising a cover surface (2) with two cover surface edges (3) tapering in the transport direction X, over which the substrate is transported in the area of a fold to be formed, and, adjacent to each of the cover surface edges (3), a curved leg surface (4), wherein at least one blowing air duct (5) for the outflow of blowing air supplied under pressure emerges from each leg surface (4) wherein the blowing air duct (5) has an outlet surface (6) on the respective leg surface (4), wherein at least one outlet surface (6) has a first extension a and a second extension b, the first extension a being greater than the second extension b, characterised in that the first extension a forms an angle of 15° to 75° with the adjacent cover surface edge (3).

2. Former nose (1) according to claim 1, characterised in that the first extension a forms an angle of 30 to 60° with the adjacent cover surface edge (3).

3. Former nose (1) according to one of claims 1 to 2, characterised in that the second extension b is in a range of 0.5 millimetres to 5 millimetres.

4. Former nose (1) according to claim 3, characterised in that the first extension a is in a range from 0.8 millimetres to 1,5 millimetre.

5. Former nose (1) according to one of claims 1 to 4, characterised in that the ratio of first extension a to second extension b is in a range of 1.5 to 15, in particular in a range of 2 to 10.

6. Former nose (1) according to one of claims 1 to 5, characterised in that the outlet surface (6) has at least one bridge (8) over the first extension a.

7. Former nose (1) according to one of claims 1 to 6, characterised in that, in the case of a plurality of outlet surfaces (6) on a leg surface (4), the outlet surfaces (6) are spaced apart from each other by a distance of 3 to 30 millimetres.

8. Former nose (1) according to one of claims 1 to 7, characterised in that at least one blowing air duct (5) inside the former nose (1) and thus spaced apart from the leg surface (4) has a cross-sectional area which is larger than the area of the outlet surface (6) resulting on the leg surface (4).

9. Former nose (1) according to one of claims 1 to 8, characterised in that the blowing air duct (5) is designed such that the blowing air emerging from the outlet surface (6) emerges essentially vertically or at an acute angle to the leg surface (4).

10. Former nose (1) according to one of claims 1 to 9, characterised in that the blowing air duct (5) is designed such that the blowing air escaping from the outlet surface (6) escapes in or against the transport direction X.

11. Former nose (1) according to one of claims 1 to 10, characterised in that the former nose (1) is made of a nickel-based alloy or tool steel or martensitic steel or a ceramic material.

12. Former board (7) for a substrate processing machine, characterised in that the former board (10) comprises a former nose (1) according to one of claims 1 to 11.

13. Method for manufacturing a former nose (1) according to one of claims 1 to 11, characterised in that the former nose (1) is manufactured using an additive manufacturing process.