DE10349890B4 - Device for longitudinal cutting of a web - Google Patents

Abstract

Device for longitudinal cutting of a paper web (02), arranged behind a last of the paper web (02) associated printing unit of a printing press, with a rotating knife (05), which against a the paper web (02) leading support member (01) can be adjusted, wherein
A surface (10) of the support element (01) in a region facing the paper web (02) has a multiplicity of microapertures (03) with a diameter of less than 500 μm for the exit of a pressurized fluid,
- The micro-openings (03) are designed as open pores of a fluid flowing through the porous material (06),
- The microporous material (06) is formed as a layer (06) on a load-bearing, but at least partially fluid-permeable support (07),
- And the surface (10) has a groove (15) into which the rotating knife (05) immersed in such a way that there is no mechanical contact between the knife (05) and the support element (01).

Description

The The invention relates to a device for longitudinal cutting of a web according to the preamble of Claim 1.

From the EP 12 38 935 A2 a device for longitudinal cutting of films and tapes is known, wherein the band-shaped material is guided over a lower blade shaft with at least one designed as a cutting groove bottom blade, and is cut by means of an engaging in the groove upper blade.

The EP 11 44 292 B1 shows a guide element for webs, which has on a frame a plate-shaped, porous, from an underlying chamber air-flow material. The guide element guides the web without contact, while it is provided on the opposite side, for example by means of a coating device with an adhesive.

The EP 07 05 785 A2 discloses a guide element, wherein in one embodiment, microporous material having pore sizes of 7 to 10 microns is traversed by air and in another embodiment, holes for the passage of air on the inside of the tube has a diameter of 0.35 mm. ie 350 microns, and the outwardly directed openings have a diameter of 1.58 mm, ie 1580 microns have.

By the DE 695 16 233 T2 a device for longitudinal cutting is known, in which a standing knife is employed on the surface of an air bearing rod, through whose jacket - for example, produced by sintering - extend about 2 microns in size holes.

In the US 5,406,869 is a flat support member of a cutting device disclosed, the surface is provided at the side of a cooperating with a rotating knife cutting groove with about 750 micron large, air-flow openings.

Of the Invention is based on the object, a device for longitudinal cutting to create a freshly printed paper web which is reliable and very accurate, d. H. without smearing fresh paint, works.

The The object is achieved by the Characteristics of claim 1 solved.

The particular advantages of the invention are that one reliable and very accurate device for longitudinal cutting a web z. B. web is created. By the formation of an air cushion between as a lower knife body executed support element or abutment and the web is on the one hand a contact, and therefore a greasing, for example, a printed and not yet Completely dried sheet prevented. In particular, there is no torque transmission from the web to the lower knife body instead, which in particular at changing machine speeds otherwise in the web tension and stretching difficulties. Second, in one execution any mechanical contact between the upper and lower blades avoided which leads to significantly reduced wear.

By the micro-openings an air cushion is formed, which is very homogeneous and a small Fluid flow required.

through in other applications z. T. used air outlet openings or nozzles with diameters in the millimeter range are selective on the material personnel (Pulse of the beam) can be applied, by means of which this of the relevant Component is kept away while through a distribution of micro-openings with high hole density support and primarily the effect a trained air cushion comes into play. The danger of a Fluttering of the web due to the strong air blasts is reduced. This results in significantly different effects out. While at Lifting the web by means of blowing air nozzles this through the pulse the air jet itself is deflected, is in training with microopenings the web through the air cushion only from the surface of the support means kept away and by raising or lowering the latter the track profile set. The distance between the surface carrying the openings and the web is reduced, the volume flow of fluid lowered considerably.

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 ).

The microopenings can advantageous as open pores on the surface of a porous, in particular microporous, air-permeable Materials executed be.

Around in the case of the use of microporous material, a uniform distribution from on the surface the material to escape air without high Layer thickness of the material with high flow resistance is needed it is appropriate that the microporous Material applied as a layer on a solid, air-permeable support is. Such a carrier can be acted upon with compressed air, which comes out of the carrier through the microporous Layer flows and so on the surface of the component forms an air cushion.

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

Around a uniform air distribution It is also to achieve desirable, that the thickness of the layer at least the distance between adjacent openings of the carrier equivalent.

embodiments The invention are illustrated in the drawings and are in Following closer described.

It demonstrate:

1 a plan view of an apparatus for longitudinal cutting of a web in a design with lower blade;

2 a partial longitudinal section through a first embodiment of a rotationally symmetrical support member with porous material;

3 a cross section to the execution after 2 ;

4 a schematic diagram of a second embodiment with an alternative cross section;

5 a schematic diagram of a third embodiment with an alternative cross section;

6 a partial track width of the support element.

A paper web 02 , z. B. web 02 or substrate web 02 , a web-building and / or processing machine, e.g. As a printing press is cut longitudinally on the way through the machine by means of a device for longitudinal cutting in partial webs. In particular, the track 02 cut in the case of a printing machine in partial webs, which correspond in width in each case an integer multiple of an applied pressure side. Also, only or additionally, a narrow edge strip can be removed. The device is also applicable to cutting devices in which the web 02 only sections cut (skip-slitter) or perforated longitudinally.

The devices for longitudinal cutting of the web 02 include a knife 05 , in particular a rotating knife 05 which by the railway 02 with a serving as an abutment support element 01 works together. The train 02 is through the support element 01 guided. For this purpose, it is expedient that the support element 01 at least slightly through the web 02 is entwined.

In 1 the device is shown, the knife 05 with a support element extending over the entire width of the web 01 works together. Although only a knife 05 is shown, for corresponding web widths, the support element 01 advantageous with several transverse to the transport direction of the web 02 spaced knives 05 work together and the train 02 Cut longitudinally into more than two partial webs. In 1 dives the knife 05 slightly into a circumferential groove 15 one whose edge is the knife 05 as a counter knife 16 , z. B. bottom knife 16 , serves. In case of multiple knives 05 or in the event that the knife 05 to be adjustable to different cutting widths are in the support element 01 several grooves 15 arranged.

Thus, for example, a surface of the web 02 , z. As a fresh coating or in particular a freshly printed, not yet dried printed image on the web 02 not by the support element 01 is damaged, it is a non-contact support element 01 using a pressurized fluid against the environment.

The lateral surface of the support element 01 has openings 03 , z. B. micro-openings 03 on, by which in operation from an inside (in 1 invisible) cavity 04 , z. B. a chamber 04 , in particular pressure chamber 04 , fluid under pressure against the environment, eg. As a liquid, a gas or a mixture, in particular air, flows. In the figures, a corresponding compressed air source is not shown.

The support element 01 points at least to the train 02 cooperating or on the train 02 facing side of its surface a surface 10 with micro-openings 03 on. It may be the openings 03 but also on others, the train 02 have non-facing sides or at least on their by train 02 acting together Longitudinal section entirely from one of the micro-openings 03 consist of material.

This simplest version without preferential direction for the arrangement of the openings 03 is through the formation of the openings 03 as micro-openings 03 possible, since this creates a thinner but more homogeneous air cushion, at the same time a required or resulting volume flow and thus a leakage current over the "open" side is considerably reduced 03 In contrast to openings with a large cross-section, the fact that "not covering" a range of openings does not lead to a kind of short-circuit current 03 sloping part resistance increased weight.

In a first embodiment ( 2 ) are the micro-openings 03 as open pores on the surface of a porous, especially microporous, air-permeable material 06 , z. B. of an open-pored sintered material 06 , in particular of sintered metal, formed. The air-permeable porous material 06 the lateral surface has pores with a size of z. B. 5 to 50 microns, in particular 10-30 microns. It is formed with an irregular, amorphous structure. The comments on the structure and training of the material 06 out 3 are in the same way to the above-mentioned embodiment without the presence of a groove 15 as well as the following examples with the material 06 apply.

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

Advantageously, the sintered surface of 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.

The support element 01 is by means of a holder 14 - at track-wide support elements 01 two holders 14 - arranged in the machine. Are transverse to the transport direction a plurality of spaced apart support elements 01 provided, so they are arranged for example on a common traverse. The holder 14 or the support element 01 is preferably changeable with respect to the frame-fixed traverse in a direction perpendicular to the web plane at a distance to the web plane. Between holder 14 and Traverse is a suitable storage, for. B. spindle drive, thread, plain bearing with adjusting means, etc., provided. Preferably, a plurality of juxtaposed support elements 01 these individually at a distance to the plane of the web 02 adjustable. For this purpose, actuators, in particular remotely operable, can be provided. In a further development, they are individually positionable or adjustable transversely to the transport direction on the traverse. Here, too, actuators can advantageously be provided which, for example, especially when remotely operable, are set at the start of production by a controller on the web width to be printed. The pressurized fluid can via a supply 13 ( 1 ) in the cavity 04 be supplied.

The knife 05 is by means of a holder 18 , z. B. plunger 18 , on a frame-fixed mount 19 , z. B. Traverse 19 arranged. Are transverse to the transport direction a plurality of spaced apart knives 05 provided, these are, for example, at the common traverse 19 arranged. In an advantageous embodiment, the knife 05 or the knife 05 carrying holder 18 transverse to the transport direction on the traverse 19 positionable or adjustable. It can be advantageously provided actuators, which, for example, especially when remote-controlled, are set at the start of production by a control on the part web width to be cut. Between holder 18 and traverse 19 is then a suitable, not shown storage, for. B. spindle drive, thread, plain bearing with adjusting means, etc., provided. The holder 18 or the knife 05 can in training regarding the frame-fixed Traverse 19 in a direction perpendicular to the orbital plane at a distance from the orbital plane to be made variable or adjustable. Preferably, in the case of several juxtaposed knives 05 these individually at a distance to the plane of the web 02 adjustable. For this purpose, actuators, in particular remotely operable, can be provided.

To get a uniform distribution of on the surface of the microporous material 06 Air to escape, without high layer thickness of the material 06 to require with correspondingly increased flow resistance, it is expedient in an advantageous embodiment that the support element 01 a solid, at least partially air-permeable carrier 07 , z. B. inner body 07 in particular basic body 07 having on which the microporous material 06 as a layer 06 is applied ( 2 and 3 ). Such a carrier 07 can be acted upon with compressed air coming from the carrier 07 out through the microporous layer 06 flows and so on the surface of the support element 01 an air cushion trains. The porous material 06 is used as a coating 06 on a bushings 08 or through holes 08 having, in particular metallic, carrier material executed. The layer 06 is over its entire layer length and entire layer width each on a plurality of support points of the carrier 07 supported. The carrier 07 has z. B. on his with the layer 06 together acting width and length in each case a plurality of non-contiguous passages 08 on.

Im in 2 and 3 illustrated embodiment, the carrier material takes substantially the weight, torsion, bending and / or shear forces in the layer 06 provided area, which is why a corresponding wall thickness (for web-wide support elements 01 z. B. greater than 5 mm, in particular 8 to 15 mm) of the carrier 07 and / or a suitably stiffened construction is selected. The z. B. the cavity 04 to the shift 06 towards limiting, or by appropriate shaping the cavity 04 total forming carrier 07 points to the with the porous material 06 coated side a plurality of openings for supplying the compressed air into the porous material 06 on. Also in the openings of the wearer 07 can be in the area of the walls z. T. porous material 06 are located. Through the cavity 04 and the z. B. as holes 08 executed through holes 08 In operation, a fluid, for. B. gas, blown, which z. B. by a compressor, not shown, under a pressure P is greater than the ambient pressure.

The carrier 07 or the resulting surface of the layer 06 can in principle with any external profile, but advantageous to the train 02 be executed convex arched profile. The carrier 07 or the resulting surface of the layer 06 can with curved or curved surface, z. B. circular segment or half shell-shaped, but also be designed as a segment of a hyperbola or ellipse. The carrier 07 can by appropriate shaping total the cavity 04 but then preferably only on that of the web 02 facing side with holes 08 provided and coated. It is essential that the carrier 07 in the area of its first point of contact with the train 02 has an inclined surface in the manner of a ramp.

The support element 01 has at least in the region of its surface, which work together with the web for that 02 is provided, at least the material 06 and possibly the one with openings 08 provided carrier 07 on ( 2 and 3 ). The porous material 06 extends continuously over the train 02 cooperating area, thus forming a continuous surface. In the embodiment according to 2 and 3 is the support element 01 or the carrier 07 formed with rotationally symmetrical cross-section. The carrier 07 is as metallic, the holes 08 having exhibiting tube, which on its lateral surface, the layer 06 wearing. The rotationally symmetrical support element 01 Can be rotatable in one embodiment in the holders 14 is stored, it is then fully through holes 08 , the layer 06 - and in the case of 1 the groove 15 - having. In another embodiment, the support element 01 rotatably in the holders 14 be arranged. Through openings 08 , Layer 06 and possibly groove 15 However, as mentioned above, they can nevertheless be provided in full or only in an area which supports the track 02 is provided.

In the support elements designed as rotationally symmetrical 01 can the volume of the cavity 04 be reduced in that an unillustrated inner tube coaxial with the carrier 07 is arranged. This will be the cavity 04 on the between inner tube and carrier 07 reduced, which results in shorter reaction times in the pressure build-up and the support element 01 additionally gives a higher stiffness.

4 shows a cross section of a second embodiment of the support element 01 , which with porous layer 06 is shown. An existing groove 15 for the knife 05 in the area 10 is not shown.

The support element 01 is in 4 with respect to a rotation axis transversely to the transport direction not rotatable, z. B. as a fixed air rod 01 , executed. It has a part-circular circumference, wherein the holes 08 having carriers 07 either the cavity 04 can fully include or, as shown, together with a firmly connected support body 09 together the cavity 04 includes. The ones with the micro-openings 03 provided area 10 can have the special case of a circle segment with an angle γ of 180 ° and then forms a half-shell.

5 shows a cross section of a third embodiment of the support element 01 , The micro-openings 03 having carriers 07 is here as a solvable use 07 or as several in the axial direction juxtaposed inserts on a support body 09 educated. An existing groove 15 for the knife 05 in the area 10 is not shown. The use 07 is detachable or changeable with the support body 09 connected. The latter is advantageous with respect to a cleaning or an exchange of inserts 07 with different coating 06 for adaptation to different materials (mass and / or surface structure) and web widths. In a variant of this embodiment with substantially fully arranged inserts 07 can such inserts 07 for example, on one in the cavity 04 extending support body 09 be arranged. However, an embodiment is advantageous, as shown, the micro-open calculations 03 having use 07 is formed only over an angular segment with a - adapted in particular to the web - curvature. The releasable connection can be as shown by the edges of the insert 07 receiving grooves 17 in the supporting body 09 be realized. In addition or instead, however, a connection can be made by screwing or by bracing.

6 shows an embodiment of the support element 01 , An essential difference to the aforementioned examples is here that the support element 01 not railway wide, but only partially or partially railway broad is listed. The above teachings regarding the rotatability or rotationally fixed arrangement, the formation with porous material 06 with carrier 07 and the training in the various cross sections are on the example of the part-wide support member 01 apply mutatis mutandis. In part here is a support element 01 to understand which the train 02 not supported on its entire width, but only on one section.

The cavity 04 is here by a designed as an annular hollow profile carrier 07 formed, which on its outer surface the layer 06 having. The annular hollow profile can rotate or non-rotatably on a holder, not shown 14 be arranged. In the example shown, the layer 06 a circumferential groove 15 on. In an advantageous embodiment, the partial web width support element 01 in a direction transverse to the transport direction of the web 02 arranged movable or adjustable.

For those with porters 07 Examples carried out include the porous material 06 outside the execution 08 a layer thickness that is less than or equal to 10 mm. A proportion of open area in the area of the effective outer surface of the porous material 06 , 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 the distance of adjacent openings of the carrier 07 equivalent. A distance of the holes 08 amounts, for example, to less than or equal to 8 mm.

The carrier 07 can also be made of porous material 06 , but with a better air permeability - z. B. a larger pore size - than that of the microporous material of the layer 06 be executed. In this case, the openings of the wearer 07 through open pores in the area of the surface, and the bushings 08 formed by the randomly formed on the porosity inside the channels. The carrier 07 but also from any, the cavity 04 overall enclosing, with bushings 08 be formed flat material or molded material. Combinations of these alternatives are also possible.

01

Abutment, Support element, air bar

02

Train, Material web, substrate web, paper web

03

micro-opening

04

Cavity, Chamber, pressure chamber

05

knife

06

microporous material, Sintered material, layer, microporous, coating

07

Carrier, inner body, body, insert

08

Bushing, through-hole, drilling

09

supporting body

10

Surface, outer surface

13

feed

14

holder

15

recess groove

16

Against knife, lower blade

17

groove

18

Holder, tappet

19

Bracket, traverse

γ

angle

Claims (31)

Device for longitudinal cutting of a paper web ( 02 ) arranged behind a last of the paper web ( 02 ) associated printing unit of a printing press, with a rotating knife ( 05 ), which against a the paper web ( 02 ) leading support element ( 01 ), wherein - an area ( 10 ) of the support element ( 01 ) in one of the paper webs ( 02 ) facing a plurality of micro-openings ( 03 ) having a diameter of less than 500 μm for the discharge of a pressurized fluid, 03 ) as open pores of a porous material through which the fluid flows ( 06 ), - the microporous material ( 06 ) as a layer ( 06 ) on a load-bearing, but at least partially fluid-permeable carrier ( 07 ), and - the surface ( 10 ) a groove ( 15 ) into which the rotating knife ( 05 ) in such a way that no mechanical contact between the knife ( 05 ) and the support element ( 01 ) consists. Apparatus according to claim 1, characterized in that the paper web ( 02 ) facing surface ( 10 ) at least slightly from the paper web ( 02 ) is entwined. Device according to claim 1 or 2, characterized in that the supporting element ( 01 ) substantially non-contact with the paper web ( 02 ) works together. Device according to claim 1, characterized in that at the bottom of the groove ( 15 ) Micro-openings ( 03 ) porous material ( 06 ) is provided. Device according to claim 1, characterized in that the surface ( 10 ) at least in one for interaction with the paper web ( 02 ) area substantially curved, in particular convex is executed. Device according to claim 1 or 2, characterized in that the surface ( 10 ) at least in one for interaction with the paper web ( 02 ) has substantially a circular profile. Device according to claim 1 or 2, characterized in that the surface ( 10 ) at least in one for interaction with the paper web ( 02 ) has substantially a part-circular profile. Apparatus according to claim 1, characterized in that an average pore size of the fluid-permeable porous material ( 06 ) of 5 to 50 microns, especially 10-30 microns, is located. Device according to claim 1, characterized in that the porous material ( 06 ) as an open-pore sintered material ( 06 ), in particular as a sintered metal is formed. Device according to claim 1, characterized in that the carrier ( 07 ) on his layer ( 06 ) facing side at least one with the layer ( 06 ) and a plurality of openings for the supply of the fluid in the layer ( 06 ) having. Device according to claim 1, characterized in that the layer ( 06 ) in the region of the support surface has a thickness less than or equal to 10 mm. Device according to claim 1, characterized in that the carrier ( 07 ) on his with the layer ( 06 ) acting together width and length respectively a plurality, in particular non-contiguous passages ( 08 ) having. Device according to claim 1, characterized in that the carrier ( 07 ) as a cavity ( 04 ) enclosing hollow profile body is formed. Device according to claim 1, characterized in that the layer ( 06 ) supporting wall of the carrier ( 07 ) at least in one for interaction with the paper web ( 02 ) area substantially curved, in particular convex is executed. Device according to claim 1, characterized in that the layer ( 06 ) supporting wall of the carrier ( 07 ) at least in one for interaction with the paper web ( 02 ) has substantially a part-circular or circular profile. Apparatus according to claim 1, characterized in that a wall thickness of the carrier ( 07 ) or at least the layer ( 06 ) bearing wall is greater than 5 mm, in particular 8 to 15 mm. Apparatus according to claim 1, characterized in that an opening degree on the outwardly facing surface of the porous material ( 06 ) is between 3% and 30%, preferably between 10% and 25%. Apparatus according to claim 1, characterized in that 1-20 standard cubic meters of air per hour per square meter of the micro-openings ( 03 ) emerge having lateral surface. Apparatus according to claim 1, characterized in that 2-15, in particular 3-7, standard cubic meters of air per hour per square meter of the micro-openings ( 03 ) emerge having lateral surface. Device according to claim 1, characterized in that the porous material ( 06 ) is pressurized from the inside with at least 1 bar overpressure. Device according to claim 1, characterized in that the porous material ( 06 ) From the inside with more than 4 bar, in particular with 5 to 7 bar, pressure is applied to the fluid. Device according to claim 1, characterized in that that the pressurized fluid is designed as compressed air. Device according to claim 1, characterized in that the support element ( 01 ) Is arranged in a direction perpendicular to the orbital plane movable. Device according to claim 1, characterized in that the support element ( 01 ) over the entire web width. Device according to claim 1, characterized in that the support element ( 01 ) partial web width is executed. Apparatus according to claim 23, characterized ge indicates that the support element ( 01 ) in its area ( 10 ) a plurality, transversely to the transport direction of the paper web ( 02 ) spaced apart grooves ( 15 ) having. Device according to claim 1, characterized in that the support element ( 01 ) is arranged rotatably with respect to a side frame. Device according to claim 1, characterized in that the support element ( 01 ) With respect to. A side frame is arranged rotationally fixed. Device according to claim 24, characterized in that the support element ( 01 ) in a direction transverse to the transport direction of the paper web ( 02 ) is arranged in a variable position. Device according to claim 1, characterized in that the knife ( 05 ) Is arranged in a direction perpendicular to the orbital plane movable. Device according to claim 1, characterized in that the knife ( 05 ) in a direction transverse to the transport direction of the paper web ( 02 ) is arranged in a variable position.