EP1556300B1 - Guiding elements for a strip-producing or strip-processing machine - Google Patents

Abstract

A folding element for a printing press, or sheet handler, has the folding guide (03) with a microporous surface to generate an air cushion and thereby prevent mechanical contact between the guide and the sheets. The pore size is less than 500 microns and the pores are evenly distributed over the surface of the guide. Air is blown through the porous surface from inside the hollow guide.

Description

The invention relates to guide elements, in particular turning bars, a web-forming or -processing machine according to the preamble of claim 1 or 2.

From the DE 93 20 281 U1 is designed as a turning bar Bahnleitelement known, which is in relation to an incoming web in at least two angular positions can be brought. When pivoting from one to the other position, openings of an inner body relative to openings of an outer body of the turning bar are displaced relative to one another such that the unused air outlet openings are closed.

By the US 37 44 693 A In one exemplary embodiment, a turner bar is disclosed, wherein a tube wall segment of porous, air-permeable material together with a base body forms a closed pressure chamber. The porous segment forms a wall of the chamber and load carrying over its width - without load-bearing pad - executed. In a second example, a segment having through holes is arranged instead of the porous segment.

The US 54 23 468 A shows a guide element, which has a bore-containing inner body and an outer body made of porous, air-permeable material. The holes in the inner body are provided only in the expected wrap.

The JP 06 198836 A discloses a turner bar, which is made of porous porous sintered metal with fluid-permeable openings of 10 to 30 microns.

By the WO 00/39011 discloses devices for guiding a web whose wall between a feed space for pressurized fluid and the guide surface are made fully walled and self-supporting porous material with average pore diameter of less than 500 microns.

In the US 5423 468 A is arranged on a load-bearing body of a guide element, a sleeve of porous material with pores of a size of about 25 microns. The main body has on the looped by the web side holes for the passage of compressed air.

The DE 31 31 621 A1 shows a turning bar with two longitudinal half-shell-like in cross-section chambers which, depending on the position of the turning bar to the web optionally interact with this.

By the DE 101 15 916 A1 discloses a turner bar with in a longitudinal section substantially arranged around the entire circumference openings for the discharge of compressed air, which is in relation to an incoming web in at least two angular positions can be brought. The openings are associated with two substantially half-shell-like halves of the cylindrical surface of the guide element.

The DE 31 27 872 A1 shows a pivotable turning bar, at the one sliding end via a telescopic tube and an opening in the turning bar blowing air is supplied.

The EP 0 705 785 A2 deals with the transport and the deflection of band-shaped material, in particular in the form of z. B. footage. Only in the respective wrapping area are designed as open micropores or micro-holes executed air outlet openings.

The invention is based on the object with respect to the change in direction of a Path to create flexible and easy to produce vanes.

The object is achieved by the features of claim 1 or 2.

The achievable with the present invention consist in particular that without great structural complexity, a flexible to the track inclinable guide element is created, which is characterized by an air cushion with a high degree of homogeneity and low losses at the same time.

With the conventional openings punctiform on the material forces (pulse of the beam) can be applied, by means of which it is employed by the relevant component, or to another component, while by a distribution of micro holes with high hole density, a broad support and primarily the effect a trained air cushion comes into play. Previously used holes were in cross section, for example, 1 to 3 mm, whereas for the micro-openings, the cross-section is smaller by at least one order of magnitude. This results in significantly different effects. For example, the distance between the surface carrying the openings and the web can be reduced, the volume flow of fluid can be lowered considerably and, as a result, leakage losses that occur outside the effective range with the web can be significantly reduced.

In contrast to known components with conventional openings or holes of opening cross sections in the range of millimeters and a hole spacing of several millimeters, a much more homogeneous surface structure is advantageously created in the formation of micro-openings on the surface. Under micro-openings here are understood openings on the surface of the component, which have a diameter less than or equal to 500 microns, advantageously less than or equal to 300 microns, in particular less than or equal to 150 microns. A "hole density" for the surface provided with the micro-openings is at least one micro-opening per 5 mm ² (= 0.20 / mm ² ), advantageously at least one micro-opening per 3.6 mm ² (= 0.28 / mm ² ).

As a result of the formation of the openings as microapertures, the air cushion is made uniform and the volumetric flow exiting per unit area is reduced in such a way that a leakage current can be reasonably small even in regions which are not looped around by the web.

The microapertures can advantageously be designed as open pores on the surface of a porous, in particular microporous, air-permeable material or else as openings of through holes of small cross-section which extend outwardly through the wall of a supply chamber. Although the following exemplary embodiments primarily show the guide element in the version with porous material, the embodiment with through holes are equally applicable to the principle of the pivotable turning bar shown there.

In order to achieve a uniform distribution of air exiting the surface of the material in the case of the use of microporous material, without simultaneously requiring high layer thicknesses of the material with high flow resistance, it is expedient that the component has a solid, air-permeable support on which the microporous material is applied as a layer. Such a carrier can be acted upon with compressed air, which flows out of the carrier through the microporous layer and thus forms an air cushion on the surface of the component.

This support, in turn, may be porous with better air permeability than that of the microporous material; but it can also be formed from a cavity enclosing, provided with air passage openings flat material or molded material. Combinations of these alternatives are also possible.

In order to achieve a uniform air distribution, it is also desirable that the thickness of the layer at least the distance of adjacent openings of the carrier equivalent.

In the case of the use of micro-bores, an embodiment is advantageous, wherein the web-facing and the micro-openings having side of the guide element is formed as one or more inserts in a carrier. The insert can be releasably and possibly changeable connected with the carrier in training. Thus, it is possible to clean and / or exchange inserts of different types of microperforations for adaptation to different materials and web widths.

Embodiments of the invention are illustrated in the drawings and will be described in more detail below.

Fig. 1

eine schematische Darstellung der Wendestange in einer ersten a) und einer zweiten b) Stellung;

Fig. 2

einen perspektivischer, teilweise aufgebrochener Schnitt der Wendestange mit Träger und vollumfänglicher Beschichtung mit porösem Material;

Fig. 3

einen perspektivischen Schnitt der Wendestange mit vollumfänglich angeordneten Mikrobohrungen;

Fig. 4

eine schematische Darstellung für eine verschwenkbare Wendestange in anderer Ausführung;

Fig. 5

einen Schnitt durch eine Wendestange nach Fig. 4.

Show it:

Fig. 1

a schematic representation of the turning bar in a first a) and a second b) position;

Fig. 2

a perspective, partially broken section of the turning bar with carrier and full coating with porous material;

Fig. 3

a perspective section of the turning bar with fully arranged microbores;

Fig. 4

a schematic representation of a pivotable turning bar in another embodiment;

Fig. 5

a section through a turning bar after Fig. 4 ,

A guide 01, z. B. Bahnleitelement 01, is used in a train-producing or - processing machine, for. As a paper machine, winding machine, packaging machine or in particular printing machine, the leadership or a change of direction of a run on the guide element 01 web 02, z. B. web 02 or substrate web 02, in particular paper web 02. The guide 01 is in particular designed as a so-called. Turner 01, by means of which- depending on their position relative to the direction of the incoming or incoming web 02 -by looping the turning bar 01 for Bahn 02 a change of direction by about + 90 ° or about -90 ° is effected. The turning bar 01 may serve as a pair of two parallel turning bars 01 inclined at 45 ° to the web transporting direction for lateral offset, or as a pair of turning bars 01 inclined at 45 ° and 45 ° respectively to the web transporting direction to incline the web 01 at 90 ° to each other , Advantageously, a plurality of turning bar pairs are arranged.

The turning bar 01 or the turning bar pair can be arranged after a printing unit and before a folding apparatus or after a dryer and before a folder of a rotary printing machine. It has z. Example, an outer diameter of 60 - 100 mm and, for example, a length of more than 1,200 mm. In this case, the turning bar 01 (or both turning bars 01 respectively) at least two positions and is (or are) in particular pivotable through 90 °, wherein in a first position, a first half of the lateral surface in the circumferential direction is wrapped by a web 02 ( Fig. 1a ) and in a second position, a second half of the lateral surface is looped ( Fig. 1b ).

The lateral surface of the turning bar 01 has openings 03, z. B. micro-openings 03, through which in operation from an internal cavity 04, z. B. a chamber 04, in particular pressure chamber 04, under overpressure against the environment fluid standing, z. As a liquid, a gas or a mixture, in particular air, flows. In the figures, a corresponding supply of compressed air into the cavity 04 is not shown.

The turning bar 01 has on its lateral surface in the circumferential direction both on the looped in the respective operating situation side and on the not covered by the web 02, d. H. the opposite side micro-openings 03 on. At least on a longitudinal section of the turning bar 01 provided for wrapping, the latter thus has micro openings 03 distributed over the full circumference of 360 ° (facing as well as the opposite side). In a preferred embodiment, no device or mechanism is provided for the turning bar 01, which (r) in operation prevents the flow of fluid from the cavity 04 through the micro-openings 03 on the side facing away from the web 02. D. h., The micro-openings 03 are in each of the at least two mentioned operating situations in a complete peripheral region of 360 ° with fluid flowed through or flows through. Switching the turning bar 01 from one to the other position requires only a pivoting, and no additional covering the openings or no interruption of the passageway between the cavity 04 and micro-opening 03.

This simple design is made possible by the formation of the openings 03 as micro-openings 03 makes sense, as hereby created a thinner but more homogeneous air cushion, at the same time a required or resulting volume flow and thus a leakage current on the "open" side is significantly reduced. The high resistance of the micro-apertures 03, in contrast to large-cross-section apertures, causes "not capping" a range of apertures to result in a sort of short-circuit current. In the total resistance of the falling over the openings 03 partial resistance receives an increased weight.

In a first embodiment, the micro-openings 03 as open pores on the surface of a porous, in particular microporous, air-permeable material 06, z. B. of an open-pore sintered material 06, in particular of sintered metal formed. The Pores of the air-permeable porous material 06 have an average diameter (average size) of less than 150 microns, z. B. 5 to 60 microns, in particular 10 to 30 microns. The material 06 is formed with an irregular, amorphous structure.

Choice of material, dimensioning and pressurization are selected such that 1 to 20 standard cubic meters per m ² , in particular 2 to 15 standard cubic meters per m ² , emerge from the air outlet surface of the sintered material 06 per hour. Particularly advantageous is the air outlet of 3 to 7 standard cubic meters per m ² .

Advantageously, the sintered surface from the cavity 04 out with an overpressure of at least 1 bar, in particular more than 4 bar, applied. Particularly advantageous is an application of the sintering surface with an overpressure of 5 to 7 bar.

If the cavity 04 of the turning bar 01, at least on its longitudinal section cooperating with the web 01, is formed essentially solely from a body of porous solid material forming the cavity 04 (that is to say without further load-bearing layers), then this z. B. tubular body formed substantially self-supporting with a wall thickness of greater than or equal to 2 mm, in particular greater than or equal to 3 mm. Possibly. can run in the cavity 04, a carrier on which the body can be selectively or partially supported, but which is not the entire surface in operative contact with the body.

In order to achieve a uniform distribution of exiting air at the surface of the microporous material 06, without simultaneously requiring high layer thicknesses of the material 06 with correspondingly increased flow resistance, it is expedient in an advantageous embodiment that the turning bar 01 a solid, at least partially air-permeable support 07, on which the microporous material 06 is applied as layer 06 ( Fig. 2 ). Such a carrier 07 can be acted upon with compressed air, which out of the carrier 07 through the microporous layer 06th flows and so on the surface of the turning bar 01 forms an air cushion. In a preferred embodiment, the porous material 06 is thus not designed as a supporting solid body (with or without frame construction), but as a coating 06 on a bushings 08 or through holes 08 having, in particular metallic, carrier material. By "non-bearing" layer 06 in conjunction with carrier 07, in contrast to "supporting" layers known from the prior art, for example, a structure is understood, layer 06 extending over a whole layer length and entire layer width on a plurality of support points the carrier 07 is supported. The carrier 07 has z. B. on its acting together with the layer 06 width and length each have a plurality of non-contiguous passages 08. This embodiment is distinctly different from a design in which a porous material extending over the entire width cooperating with the web 02 is self-supporting over this distance, is supported on a frame or carrier only in one end region, and therefore a corresponding one Must have strength.

In the illustrated embodiment, the carrier material absorbs substantially the weight, shear, torsion, bending and / or shear forces of the component, which is why a corresponding wall thickness (eg greater than 3 mm, in particular greater than 5 mm) of the carrier 07 and / or a suitably stiffened construction is selected. The z. B. the cavity 04 to the layer 06-limiting, or by appropriate shaping (eg., Tubular) forming the cavity 04 has on the side coated with the porous material a plurality of openings 09 for supplying the compressed air into the porous material 06 on. Also in the openings 09 of the carrier 07 may be in the region of the walls z. T. porous material are.

The porous material 06 outside the bushing 08 has a layer thickness which is less than 1 mm. Particularly advantageous is a layer thickness between 0.05 mm and 0.3 mm. A proportion of open area in the area of the effective outer surface of the porous material, here designated opening degree, is between 3% and 30%, preferably between 10% and 25%. In order to achieve a uniform air distribution, it is also desirable that the thickness of the layer at least equal to the distance of adjacent openings 09 of the carrier 07.

The emerging from the sintered material 06 compressed air occurs in both positions of the turning bars in the circumferential direction completely, d. H. essentially over 360 °, out.

According to Fig. 2 illustrated embodiment is arranged as a support 07 or inner body 07 in the turning bar 01 a support tube 07 with any, but advantageous annular profile, wherein the wall thickness of the support tube 07 is greater than 3 mm, in particular greater than 5 mm. The carrier tube 07 has a plurality of passages 08 with openings 09 for supplying the compressed air into the porous material 06.

The possibly also designed as a support tube 07 carrier 07 may in turn, however, also made of porous material, but with a better air permeability -. B. a larger pore size - be designed as the microporous material of the layer 06. In this case, the openings 09 of the carrier 07 are formed by open pores in the region of the surface, and the passages 08 are formed by the randomly formed via the porosity inside the channels. However, the support 07 can also be formed from any desired, the cavity 04 enclosing, provided with bushings 08 flat material or molded material. Combinations of these alternatives are also possible.

The inner cross section of a feed line, not shown, for supplying the compressed air to the turning bar is less than 100 mm ² , preferably between 10 and 60 mm ² .

In a second embodiment ( Fig. 3 ) are the micro-openings 03 as openings through holes 11, in particular microbores 11 executed, which is characterized by a z. B. as a pressure chamber 04 formed cavity 04 delimiting wall 12, z. B. chamber wall 12, extend outward. The holes 11 have z. B. a diameter (at least in the region of the openings 03) of less than or equal to 500 .mu.m, advantageously less than or equal to 300 .mu.m, in particular between 60 and 150 .mu.m. The opening degree is z. B. at 3 to 25%, especially at 5 to 15%. A hole density is at least 1/5 mm ² , in particular at least 1 / mm ² up to 4 / mm ² . The wall 12 thus has, at least in one of the web 02 opposite region, a microperforation. Advantageously, the microperforation extends - as in the first embodiment, the bushings 08 and layer 06 - to the full extent of 360 °.

One u.a. the flow resistance influencing wall thickness of the holes containing chamber wall 12 is z. B. at 0.2 to 3.0 mm, advantageously at 0.2 to 1.5 mm. in particular from 0.3 to 0.8 mm. In the interior of the turning bar 01, in particular in the cavity 04, a reinforcing construction, not shown, for example, in the longitudinal direction of the turning bar 01 extending carrier, in particular metal support, be arranged on which the chamber wall 12 is at least partially or selectively supported.

The chamber 04 enclosing wall 12 is z. B. by a hollow profile body, preferably a tubular hollow profile body, in particular a hollow profile body formed with annular profile.

For the execution of the micro-openings 03 as openings 03 of holes 11 z. B. an overpressure in the chamber 04 of 0.5 to 2 bar, in particular from 0.5 to 1.0 bar of advantage.

The holes 11 may be cylindrical, funnel-shaped or other special Shaping (eg in the form of a Laval nozzle) be executed.

The microperforation, d. H. the bores 11 are preferably produced by drilling by means of accelerated particles (eg liquid such as water jet, ions or elementary particles) or by means of electromagnetic radiation of high energy density (eg light by means of a laser beam). Particularly advantageous is the production by means of electron beam.

The web 02 facing side of the holes 11 having wall 12, z. As a wall 12 formed of stainless steel, in a preferred embodiment, a dirt and / or color-repellent finish. It has a not shown, the openings 03 and holes 11 not covering coating -. As nickel or advantageous chromium - on which z. B. is additionally processed - z. B. structuring with micro ribs or a lotus flower effect structuring or preferably highly polished).

The holes having the wall is formed in a variant as one or more inserts in a carrier. The insert may be fixed or changeable connected to the carrier. The latter is advantageous with respect to a cleaning or an exchange of inserts of different types of microperforations for adaptation to different materials and web widths. In the embodiment with substantially fully arranged openings 03, such inserts may for example be arranged on a running in the cavity 04 carrier.

In another example ( Fig. 4 ) for a pivotable turning bar 01 a plurality of chambers 04 are arranged in this, each chamber 04 is a part of the lateral surface of the turning bar 01 (sintered surface as shown or microperforated surface, not shown) is assigned in the circumferential direction. Each chamber 04 is selectively acted upon by compressed air, so that in each position, the respective looped region of the turning bar 01 is subjected to compressed air. For this embodiment are z. B. at the turning bar 01 at least two optionally be acted upon with compressed air supply lines 13 or the chambers 04 are acted upon via a multi-way valve either with the source of a compressed air compressed ( Fig. 5 ).

LIST OF REFERENCE NUMBERS

01

Guide element, web guide element, turning bar

02

Web, material web, substrate web, paper web

03

Opening, micro opening

04

Cavity, chamber, pressure chamber

05

-

06

microporous material, sintered material, layer, microporous, coating

07

Carrier, inner body, support tube

08

Feedthrough, passage opening

09

opening

10

-

11

Bore, micro bore

12

Wall, chamber wall

13

supply

Claims (30)

1. A guide element of a web-producing or -processing machine with a plurality of openings (03), arranged in its generated surface at least in a longitudinal section of the guide element (01) substantially around the entire periphery, for a pressurised fluid to emerge, the guide element (01) being able to be placed in at least two angular positions with respect to an incoming web (02), characterised in that the openings (03) are in the form of micro-openings (03) with a diameter of less than 500 µm, that the micro-openings (03) are in the form of open pores of a porous material (06) through which the fluid flows, which material is formed as a layer (06) on a load-bearing support (07) which is however, at least in regions, permeable to fluid, and in that in both angular positions the fluid in this longitudinal section emerges from the micro-openings substantially over the entire periphery.
2. A guide element of a web-producing or -processing machine with a plurality of openings (03) for a pressurised fluid to emerge, the guide element (01) being able to be placed in at least two angular positions with respect to an incoming web (02), characterised in that in each of the two angular positions, both on a side facing the web (02) and around which the web (02) wraps and on an opposite side of the guide element (01) which faces away therefrom, the fluid emerges from openings (03) provided therein, in that the openings (03) are in the form of outward-directed openings (03) of microbores (11) having a diameter of less than 500 µm in a wall (12) which delimits the guide element (01) on the outside.
3. A guide element according to Claim 2, characterised in that the openings (03) in the generated surface of the guide element (01), at least in a longitudinal section of the guide element (01), are arranged substantially around the entire periphery.
4. A guide element according to Claim 1 or 2, characterised in that in both angular positions the fluid in a longitudinal section emerges from the openings (03) substantially over the entire periphery.
5. A guide element according to Claim 1 or 2, characterised in that the guide element (01) is pivotable by 90°, with in a first angular position a first, substantially half-shell-like half of the cylindrical generated surface, and in a second angular position a second half-shell-like half of the generated surface, being wrapped by the web (02).
6. A guide element according to Claim 1, characterised in that the pores of the fluid-permeable porous material have an average diameter of 5 to 50 µm, in particular 10 - 30 µm.
7. A guide element according to Claim 1, characterised in that the porous material (06) is in the form of an open-pored sintered material (06), in particular a sintered metal.
8. A guide element according to Claim 1, characterised in that the support (07) has on its side facing the layer (06) at least one supporting surface connected to the layer (06) and also a plurality of openings (09) for supplying the fluid to the layer (06).
9. A guide element according to Claim 1, characterised in that the layer (06) has in the region of the supporting surface a thickness of less than 1 mm, in particular of 0.05 mm to 0.3 mm.
10. A guide element according to Claim 1, characterised in that the support (07) has on its width and length which cooperate with the layer (06) in each case a plurality of, in particular non-coherent, through-passages.
11. A guide element according to Claim 1, characterised in that the support (07) is in the form of a support tube (07) with a hollow profile, in particular a profile in the shape of a circular ring.
12. A guide element according to Claim 11, characterised in that a wall thickness of the support tube (07) is greater than 3 mm, in particular greater than 5 mm.
13. A guide element according to Claim 1, characterised in that a degree of opening on the outward-pointing surface of the porous material (06) is between 3% and 30%, preferably between 10% and 25%.
14. A guide element according to Claim 2, characterised in that a diameter of the openings (03) is less than or equal to 300 µm, in particular between 60 and 150 µm.
15. A guide element according to Claim 2, characterised in that a wall thickness of the wall (12) is 0.2 to 3.0 mm.
16. A guide element according to Claim 2, characterised in that a hole density, i.e. a number of openings (03) per unit of surface area, for the surface provided with the micro-openings (03) is at least 0.2 / mm².
17. A guide element according to Claim 1 or 2, characterised in that 1 - 20 standard cubic metres of air per hour emerge from one square meter of the generated surface having the openings (03).
18. A guide element according to Claim 1 or 2, characterised in that 2 - 15, in particular 3 - 7, standard cubic metres of air per hour emerge on one square meter of the generated surface having the openings (03).
19. A guide element according to Claim 1, characterised in that the porous material (06) is acted upon from the inside with at least 1 bar excess pressure.
20. A guide element according to Claim 1, characterised in that the porous material (06) is acted upon by the fluid from the inside with more than 4 bar, in particular with 5 to 7 bar, excess pressure.
21. A guide element according to Claim 1 or 2, characterised in that a feed line for supplying the fluid to the guide element (01) has an internal cross-section of less than 100 mm², in particular between 10 and 60 mm².
22. A guide element according to Claim 1 or 2, characterised in that the external diameter of the guide element (01) is 60 - 100 mm.
23. A guide element according to Claim 1 or 2, characterised in that the guide element (01) has a length of greater than 1,200 mm.
24. A guide element according to Claim 1 or 2, characterised in that the guide element (01) is in the form of a turning bar (01).
25. A guide element according to Claim 1 or 2, characterised in that the pressurised fluid is in the form of compressed air.
26. A guide element according to Claim 2, characterised in that the bores (11) are produced by means of accelerated particles.
27. A guide element according to Claim 26, characterised in that the bores (11) are produced by drilling by means of an electron beam.
28. A guide element according to Claim 2, characterised in that at least one wall section of the guide element (01) which has the bores (11) has on its surface a dirt-repellent and/or ink-repellent finish.
29. A guide element according to Claim 28, characterised in that the finish is in the form of a coating by chromium.
30. A guide element according to Claim 29, characterised in that the surface is produced with a high-polish finish.

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