DE102020130360A1 - Knife cylinder and knife bar - Google Patents

Abstract

The invention relates to a cutter cylinder (1) for use in substrate-processing machines, comprising a longitudinal axis (2) about which the cutter cylinder (1) is rotatably mounted, a base body (3) for receiving at least one cutter bar (4), at least one cutter bar (4) for accommodating at least one continuous or multi-part knife strip (5), at least one fastening means (6) for fastening the at least one knife bar (4) to the base body (3). The object of the invention is to provide a solution with which the length of the cutter bar (4) can be optimally utilized in terms of the maximum working width and the cutter bar (4) can be distributed evenly over its length without being unnecessarily widened and not only connected to the base body (3) at the ends knife cylinder according to the invention (1) is characterized in that the at least one fastening means (6) as at least one through the base The cutter bar (4) according to the invention is characterized in that, on the side facing the longitudinal axis (2) of the cutter cylinder (1), it has at least has a threaded bore (7) for screwing in the at least one fastening element (6).

Description

The invention relates to a cutter cylinder for use in substrate-processing machines such as folding units of web-fed printing presses or other cutting and perforating devices for printed or unprinted substrates, comprising a longitudinal axis about which the cutter cylinder is rotatably mounted, a base body for receiving at least one cutter bar, at least a cutter bar for accommodating at least one continuous or multi-part cutter bar, at least one fastening means for fastening the at least one cutter bar to the base body.

In substrate-processing machines, especially when a web-shaped substrate is processed, such as in the folding units of web-fed rotary printing presses, perforating devices or cutting devices are used, in which the web-shaped substrate, hereinafter also referred to as web for short, is perforated transversely to its running direction and/or transversely to it is cut into individual signatures in its running direction.

Here, cross-perforation or cross-cutting devices are usually used, which consist of two counter-rotating cylinders, one cylinder of this pair of cylinders carrying the perforating or cutting knife and therefore being called knife cylinder, while the other cylinder has at least partially an elastic support. For perforating or cutting, the cutter bar of the cutter cylinder at least partially pierces the substrate and during this process at least partially dips into the elastic support of the counter cylinder.

Since it is irrelevant for the present invention whether the knife cylinder or knife bar according to the invention is used on a perforating or a cross-cutting device, only the terms knife cylinder and knife bar are used below, since the only difference between a perforating device and a cross-cutting device is the degree of penetration of the Knife bar through the substrate to be perforated or cut across.

Knife bars are known for this purpose from the prior art, in which a knife strip is clamped. Since this male connector is subject to more or less heavy wear during operation, rapid replacement of the male connector in the perforating or cross-cutting device must be ensured in order to keep the downtimes of the production device as short as possible.

For this reason, the cutter bars are usually designed in such a way that the cutter bar, which can be designed in one or more parts in the longitudinal direction of the cutter bar, can be exchanged in a cutter bar outside the perforating or cutting device, so that to replace a cutter bar only nor the prepared cutter bar on the cutter cylinder is replaced.

Solutions are known from the prior art in which the cutter bar is screwed onto the base body of the cutter cylinder from its lateral surface in the direction of the longitudinal axis of the cutter cylinder.

However, such a solution has the disadvantage that, without interrupting the cutter bar or without disproportionately widening the cutter bar, it can only be screwed onto the base body of the cutter cylinder at its two ends viewed in the longitudinal direction.

On the one hand, this affects the maximum possible length of the male connector to be clamped and thus the perforating or cutting width. On the other hand, screwing the cutter bar to the base body exclusively at the ends of the cutter bar, particularly with longer cutter bars and/or at high rotational speeds of the cutter cylinder, can result in the cutter bar deflecting in the center of the cutter bar, with the disadvantages of uneven perforation and the risk of Breakage due to the changing load of the radial deflection on the one hand and the sudden, opposite load during the cutting process on the other hand cannot be ruled out.

The invention is therefore based on the object of creating a solution with which, on the one hand, the length of the cutter bar can be optimally utilized with regard to the maximum working width and, on the other hand, the cutter bar is distributed evenly over its length and not only at the ends without an unnecessary widening can be connected to the base body.

This object is achieved by a device using a cutter cylinder according to claim 1 and a cutter bar according to claim 3. The blade cylinder according to the invention is characterized in that at least one fastening means is designed as at least one through-bolt which extends through the base body and is screwed into the blade bar.

The cutter bar according to the invention is characterized in that it has at least one threaded hole for screwing in the at least one fastening element on the side facing the longitudinal axis of the cutter cylinder.

Such an embodiment of the cutter cylinder in connection with the cutter bar has the advantage that the length of the cutter bar can be fully utilized as the working width for the perforating or cutting process.

In addition, it is possible to attach screw connections to the cutter bar over its entire length, with which the cutter bar is connected to the base body of the cutter cylinder.

In particular, with longer lengths of the cutter bar and/or with higher rotational speeds of the cutter cylinder during operation, one or more screw connections can be attached in particular in the middle of the cutter bar, which significantly reduces the deflection and the stress on the cutter bar and thus significantly reduces the risk of vibration fracture.

Thus, when using three fastening means in the sense of through-bolts distributed substantially evenly over the length of the cutter bar, the bending stress can be reduced by 85 percent compared to fastening exclusively at the ends of the cutter bar.

The use of at least three fasteners distributed substantially evenly over the extension over the cutter bar in the longitudinal direction X allows the cutter bar to be connected to the base body at at least three points, which further reduces the deflection and the bending stress associated therewith.

Since the fastening of the cutter bar on the base body according to the invention enables a uniform screw connection over the entire length without an additional widening of the cutter bar, this design allows a cutter bar with the same width to accommodate a plurality of cutter bars spaced apart from one another in the direction of rotation. This makes it possible to retrofit so-called tear-off perforations with a plurality of blade strips arranged at a distance from one another, viewed in the circumferential direction, instead of a blade bar with only one blade strip clamped therein.

According to one embodiment of the invention, the cutter bar comprises a base body, a screw-on bar that can be attached to the base body, a first clamping bar that can be attached to the screw-on bar, and a second clamping bar that can be attached to the base body, so that such a cutter bar can accommodate and thus comprise three one-piece or multi-piece knife strips spaced apart from one another perpendicularly to the longitudinal direction X of the knife bar and thus in the circumferential direction of the knife cylinder.

According to a further embodiment, a damping strip made of an elastic material is attached to at least one side of at least one, preferably all male connectors, in order to keep the substrate to be perforated or cut in a defined, compressed state during the cutting process.

According to a further embodiment, the cutter bar includes at least one adjusting element, which is preferably arranged in the base body below at least one cutter bar. In this way, the corresponding cutter bar can be aligned very easily and precisely in the radial direction of the cutter cylinder to the cutter bar before clamping using the screw-on bar or a clamp bar.

The variant which comprises at least two adjusting elements under each male connector, which are preferably attached to both ends of the respective male connector, is particularly preferred here. In this way, the exact height as well as the parallelism of the cutter bar to the cutter bar can be adjusted very reliably and in a short time.

Preferred developments of the invention result from the dependent claims and the following description.

• 1 Ein Zylinderpaar umfassend einen Messerzylinder und einen Gegenzylinder
• 2 Eine dreidimensionale Ansicht eines erfindungsgemäßen Messerbalkens einschließlich den Befestigungsmitteln
• 3 Einen Querschnitt durch den erfindungsgemäßen Messerbalken mit Klemmung der Anschraubleiste
• 4 Einen Querschnitt durch den erfindungsgemäßen Messerbalken mit Klemmung der ersten Klemmleiste
• 5 Einen Querschnitt durch den erfindungsgemäßen Messerbalken mit Stellelementen

Various exemplary embodiments of the invention are explained in more detail with reference to the drawings, without being restricted thereto. It shows:

• 1 A pair of cylinders comprising a knife cylinder and an anvil cylinder
• 2 A three-dimensional view of a cutter bar according to the invention including the fastening means
• 3 A cross section through the cutter bar according to the invention with clamping of the screw-on bar
• 4 A cross section through the cutter bar according to the invention with clamping of the first terminal block
• 5 A cross section through the cutter bar according to the invention with adjusting elements

1 shows an example of a pair of cylinders 20 designed as a cross-cutting device or cross-perforating device, which includes a knife cylinder 1 and a counter-cylinder 21 .

The cutter cylinder 1 comprises, for example, a cylindrical base body 3 which has a groove into which the cutter bar 4 is embedded.

It is pointed out at this point that this representation of the cylinder pair 20 is purely an example, because it is also possible, although in 1 not shown, the base body 3 not in a cylindrical shape with a substantially circular cross-section, but with any, for example, with a substantially rectangular or prismatic cross-section.

Furthermore, it is also possible that the cutter cylinder 1 not only accommodates one cutter bar 4, but the cutter cylinder 1 can also be designed and suitable for accommodating a plurality of cutter bars 4, in particular two, three or four cutter bars 4. In the case of a knife cylinder 1 with, for example, two knife bars 4, the at least one fastening means 6 for each knife bar 4 is then at an angle to the in 1 design shown execution.

The blade cylinder 1 has a longitudinal axis 2 about which it rotates during operation.

The cutter bar 4 is suitable for accommodating at least one single or multi-part cutter bar 5, which in 1 The cutter bar 4 shown as an example has three cutter bars 5 spaced apart from one another in the circumferential direction of the cutter cylinder 1 . Each of these male connectors 5 can be designed continuously and thus in one piece over the working width, that is to say the length in the extension of the longitudinal axis 2 .

It is also possible to use multi-part male connectors 5, which consist of a plurality of male connector segments arranged next to one another over the extension of the longitudinal axis 2. However, since this aspect is essentially not relevant to the invention, the term male connector 5 is used exclusively below.

Under operating conditions, the anvil cylinder 21 rotates in the opposite direction to the knife cylinder 1, with a substrate (not shown) running through the cylinder gap. The effective peripheral speed of the two cylinders usually corresponds to the speed of the substrate in order to avoid relative speeds between the substrate and the effective surfaces of the counter-cylinder 21 and the cutter bar 4.

However, solutions are also known, for example in the case of perforation or cross-cutting devices for format-variable perforation or cutting, in which the circumferential speed during the cutting/perforating process and/or during the remaining rotation deviates from the speed of the substrate. In paper-processing machines or in the folding units of web-fed printing machines, the peripheral speed of the counter cylinder 21 and the knife cylinder 1 can thus be in the range of 18 to 20 meters per second.

During the cutting or perforating process, the at least one knife strip 5 is pressed through the substrate and dips into strips made of elastic material, which are embedded in counter cylinder 21 .

Due to the rotation of the cutter cylinder 1, the cutter bar 4 is subjected to an acceleration in the radial direction, so that a centrifugal force acts on the cutter bar 4.

If the cutter bar 4 is only connected to the base body 3 at its outer ends in the extension of the longitudinal axis 2, a considerable bending stress also acts on the cutter bar 4, which is briefly weakened by the cutting force or usually exceeded in the opposite direction, so that the cutter bar 4 is usually exposed to changing loads during operation.

For this reason, it is imperative that the cutter bar 4 is fastened to the base body 3 with sufficient certainty. For this purpose, as in 1 shown, the cutter bar 4 is attached to the base body 3 with at least one fastener 6 in such a way that the at least one fastener 6 is designed as at least one through-bolt 6 that extends through the base body 3 and is guided in a through-hole 15 through the base body 3.

This configuration of the fastening means 6 as a through-bolt makes it possible to attach a plurality of through-bolts 6 over the length of the cutter bar 4 in the extension of the longitudinal axis 2, so that the deflection and thus the bending chip tion of the cutter bar 4 can be correspondingly significantly reduced.

2 shows a three-dimensional view of a cutter bar 4 without a base body 3. The in 2 The cutter bar 4 shown comprises three attachment means 6 distributed essentially evenly over its extension in the longitudinal direction X, as in the case of the attachment of the cutter bar 4 to the base body 3 of the cutter cylinder 1 designed as through-bolts 6.

With a small width of the cutter bar 4 in the circumferential direction of the cutter cylinder 1, the cutter bar 4, in addition to its two ends extending in the longitudinal direction X, can also be fastened approximately in the middle or directly in the middle on the base body 3, which reduces the deflection and thus the bending stress is also significantly reduced.

Although not in 2 shown, it is also possible to attach more than three fastening means 6 designed as through-bolts in the longitudinal direction X of the cutter bar 4 . Alternatively, and in particular depending on the length of the cutter bar 4, it may also be sufficient to attach the cutter bar 4 to the base body 3 with only one or two fastening means 6 designed as through-bolts.

Although not in 2 shown, it is also possible to fasten the cutter bar 4, on the one hand, to the base body 3 of the cutter cylinder 1 with connecting elements attached from the envelope of the cutter cylinder 1, such as screws in particular, and at the same time to fasten the cutter bar 4 additionally with a screw, which is guided through the base body 3 To attach fasteners 6 to the base body 3.

For example, at the ends of the cutter bar 4 viewed in the longitudinal direction X, screws can be passed through the cutter bar 4 and screwed into the base body 3, while in the extension of the longitudinal direction X at least one fastener 6, such as a screw, is guided through the base body 3 and into the Knife bar 4 is screwed in.

Although due to the perspective of the cutter bar 4 in 2 not visible, it should be mentioned at this point for the sake of completeness that at the points in which the at least one fastening means 6 designed as a screw is screwed into the cutter bar 4, the cutter bar 4 has a threaded bore 7 in its base body 8.

In the case of a plurality of fastening means 6, the cutter bar 4 thus has threaded bores 7 in its base body 8, particularly preferably distributed uniformly over its extension in the longitudinal direction X, such as these in 4 is shown.

3 shows a cross section through an embodiment of the knife bar 4, as this is suitable for receiving three knife bars 5.

The cutter bar 4 comprises a base body 8, which has at least one in 3 non-illustrated threaded hole 7 for attachment to the base body 3 of the blade cylinder 1 has.

To accommodate the central male connector 5, a screw-on strip 9 is screwed onto the radially upstanding web of the base body 8 using at least one screw 14, so that the central male connector 5 is clamped between the web of the base body 8 and the screw-on strip 9.

For this purpose, the radially protruding web of the base body 8 usually has a plurality of threaded bores 7 for receiving screws 14 in order to ensure secure clamping of the central male connector 5 and that the screw-on strip 9 rests evenly on the web of the base body 8 .

In order to be able to loosen or clamp the at least one screw 14, with which the screw-on strip 9 is screwed to the radial web of the base body 8, even when the second terminal strip 11 is installed, for example to readjust the overhang of the middle male connector 5, the second terminal strip 11 instructs the at least one point at which the screw-on strip 9 is connected to the base body 8 by means of at least one screw 14 has a through hole 15, so that the at least one screw 14 can be loosened and clamped with a suitable tool, such as a hexagonal wrench, without this having to remove the second terminal strip 11.

It is irrelevant here whether the male connector 5 is designed as a one-piece male connector 5 or as a multi-part male connector 5. While a one-piece knife bar 5 extends as one component over the entire effective longitudinal direction X of the knife bar 4, multi-part knife bars 4 consist of a plurality of knife segments over the length of the knife bar 4.

To accommodate a further knife strip 5, the knife bar 4 comprises at least one further clamping strip 10.

As in 4 As can be seen, a further male connector 5 can be attached to the knife carrier 4 by screwing a first terminal connector 10 using at least one screw 14 on the side of the web of the base body 8 opposite the screw-on profile 9 so that the one located between the web of the base body 8 Male connector 5 can be fixed by clamps.

As if from a synopsis of 2 with the 4 shows, the through-holes in the screw-on strip 9 are offset from the through-holes in the first clamping strip 10 in the longitudinal direction X of the cutter bar 4, and the web of the base body 8 thus has a plurality of threaded bores 7, which are offset from one another in the longitudinal direction X of the cutter bar 4, for receiving at least a screw 14 each for the screw-on strip 9 and for the first terminal strip 10.

A third male connector 5 can be attached to the first male connector 5 and the second male connector 5 between a second terminal strip 11 and the screw-on strip 9 on the knife carrier 4 in addition to the first male connector 5 .

For this purpose, at least one screw 14 is guided through a hole in the second male connector 5 and screwed into a threaded hole 7 of the screw-on strip 9 so that the third male connector 5 can be clamped between the second terminal strip 11 and the screw-on strip 9 .

The screw-on strip 9 thus has alternating through-holes for receiving the screws 14 for clamping the screw-on strip 9 to the web of the base body 8 and threaded holes 7 for receiving the screws 14 for clamping, given a usual length of a cutter bar 4 of around 300 millimeters to around 600 millimeters the second terminal strip 11 to the screw-on strip 9.

As already in 3 as well as in 4 shown, a damping strip 12 can be attached on at least one side next to at least one, preferably next to each male connector 5. In a preferred embodiment, this at least one damping strip 12 can be clamped between at least one of the clamping strips 10, 11 and/or the screw-on strip 9 and/or the base body 8 and the respective male connector 5.

A damping strip 12 consists of an elastic material such as a foamed polyurethane and protrudes beyond the side of the clamping strip 10, 11 and/or the screwing strip 9 facing the outer envelope of the blade cylinder 1, so that the substrate is clamped at the time of perforation or cutting. Furthermore, the elasticity of the damping strip 12 prevents the completely or partially severed substrate from getting caught on the male connector 5, in that a damping strip 12 strips the substrate by expanding after the cutting process.

5 shows a further embodiment of the cutter bar 4 according to the invention, in which the cutter bar 4 comprises at least one adjusting element 13 . At the in 5 shown embodiment are in the contact surface of the cutter bar 4 on the base body 3 below each knife strip 5 threaded holes 7, in each of which a designed as a stud screw adjusting element 13 is screwed. Although not in 5 shown, it is also possible to arrange an actuating element 13 only under a male connector 5 .

With such an adjusting element 13, the height of the male connector 5 to the base body 8 can be adjusted and fixed before the respective male connector 5 is clamped in the cutter bar 4.

The adjusting elements 13 are preferably attached under each cutter bar 5, preferably in the area of the ends viewed in the longitudinal direction X of the cutter bar 4. In this way, both the overhang of the male connector 5 relative to the base body 8 and the inclination of the male connector 5 relative to the base body 8 can be precisely adjusted before the respective male connector 5 is clamped.

Reference List

1

knife cylinder

2

longitudinal axis

3

base body

4

knife bar

5

male connector

6

fasteners

7

threaded hole

8th

body

9

screw-on bar

10

first terminal strip

11

second terminal strip

12

damping bar

13

actuator

14

screw

15

through hole

20

pair of cylinders

21

counter cylinder

X

Longitudinal knife bar

Claims (9)

Knife cylinder (1) for use in substrate-processing machines, comprising a longitudinal axis (2) about which the knife cylinder (1) is rotatably mounted, a base body (3) for receiving at least one knife bar (4), at least one knife bar (4) for receiving at least one continuous or multi-part knife strip (5), at least one fastening means (6) for fastening the at least one knife bar (4) to the base body (3), characterized in that at least one fastening means (6) as at least one through the Base body (3) reaching through screw (6), which is screwed into the cutter bar (4), is executed. Knife cylinder (1) after claim 1 , characterized in that the at least one cutter bar (4) is fastened to the base body (3) with at least three fastening means (6) distributed essentially uniformly over an extension in the longitudinal direction X thereof. Knife bar (4) for use in a knife cylinder (1) according to claims 1 or 2 , characterized in that it has at least one threaded bore (7) for screwing in the at least one fastening element (6) on the side facing the longitudinal axis (2) of the blade cylinder (1). Knife bar (4) after claim 3 , characterized in that it is designed to accommodate at least two one-piece or multi-piece male connectors (5). Knife bar (4) after claim 4 , characterized in that it comprises a base body (8), a screw-on strip (9) and at least one terminal strip (10, 11). Knife bar (4) according to one of claims 3 until 5 , characterized in that the cutter bar (4) has a base body (8), a screw-on strip (9), a first clamping strip (10), a second clamping strip (11) and three one-piece or includes multi-part male connectors (5). Knife bar (4) after claim 6 , characterized in that a damping strip (12) is attached to at least one side of at least one male connector (5). Knife bar (4) according to one of claims 3 until 7 , characterized in that the cutter bar (4) comprises at least one adjusting element (13). Knife bar (4) after claim 8 , characterized in that the at least one adjusting element (13) is arranged in the base body (8) below at least one male connector (5).

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