DE2329095B2 - LONGITUDINAL SHEARS FOR ROLLED PLATES, IN PARTICULAR FOR THICK PLATES - Google Patents

Description

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The invention relates to a slitting shear for rolled sheets, in particular for thick sheets, with a an arc-shaped upper knife and a fixed, straight one Lower knife, with the upper knife compared to the lower knife according to the different Sheet thicknesses can be preset to different penetration depths.

With such slitting shears, the sheet to be cut is parallel to the with the help of so-called drivers In the longitudinal direction of the cutting edges, lifted over the lower knife table. For example about Crankshaft driven upper knife is immediately connected to each transport stroke of the sheet lowered and separates the sheet metal with a rolling movement on a section of a predetermined length in the longitudinal direction. At the end of the cut, the upper knife runs out of the sheet metal according to the knife radius, so that the The end of the cutting edge can no longer touch and damage the sheet metal surface. After completion Each cut, the sheet metal is turned by the drivers by a stroke length equal to the length of the cut is transported further, whereupon the next cut is made. The cutting work of the slitting shears is continued without interruption at constant crankshaft speed until the sheet metal is divided longitudinally over its entire length.

Experience has shown that with a scissor cut, the sheet metal is already halfway through the depth of penetration Upper knife is completely severed. From this experience you have the Obei knife with one Provided adjusting device through which a knife gap adjustment can be effected in the vertical direction can. This allows the upper knife to be adjusted vertically so that it can be used for any sheet thickness to be divided lengthways only dips into the sheet by about half the sheet metal thickness. This is to prevent the Sheet metal strips that have been cut off on the upper knife side are pushed down too far and thus towards the cutting edge is bent outwards.

There, as mentioned above, the cutting process of the slitting shear carried out without interruption at constant crankshaft speed is the one between two successive cuts for the advance transport of the sheet to The available period of time is relatively short and must therefore be used to the full if you are using economically dimensioned driver drives want to get by. That is why every transport begins for that Sheet metal to be divided lengthways immediately with the end of the cutting stroke and it only ends when the gate end the upper knife has already moved half the sheet thickness below the sheet surface, d. H. right away before starting the new cut.

In practical operation it has now been shown that the Surface of the sheet metal strip cut off on the upper knife side by half the sheet metal thickness below the Surface of the sheet metal strip lying on the lower knife table is pressed off. Depending on the In many cases, the sheet metal strip that has been cut off resiliently resists the sheet metal thickness and the strength of the material back so that the surfaces of both metal strips are again approximately on the same plane. That for Carrying out a longitudinal partial cut, the plunging upper knife therefore touches the one while it is still in motion located sheet. This not only causes scratch marks on the sheet metal surface, but also the upper knife can also be damaged.

The purpose of the invention is to eliminate these disadvantages inherent in the known slitting shears. The task is therefore to maintain the above-described mode of operation of the slitting shears Take measures to prevent sliding contact between the one still in motion Sheet and into this for the purpose of beginning a new cutting stroke plunging upper knife effective impede.

The solution to this problem is achieved according to the invention in a simple manner that before Immersion end of the upper knife on the upper knife carrier is mounted a rolling element that is slightly above the Cutting edge of the upper knife protrudes.

The rolling body can be a role according to a further feature of the invention, which is transverse to Cutting edge of the upper knife directed axis is freely rotatably mounted on the upper knife carrier.

This rolling element now touches the sheet metal in front of the upper knife and rolls as long as the sheet metal is still moving, on its surface. It thus prevents a sliding movement between the sheet and the upper knife, because the upper knife can only come into contact with the sheet metal when the transport stroke of the Sheet metal is finished.

According to another feature of the invention, the lower blade is approximately vertical at the front end a counter-pressure roller is stored below the roller located on the upper knife carrier, which is slightly above the Cutting edge of the bedknife protrudes.

This measure prevents the sheet, which is still moving, from being with the the roller lowering the upper knife is pressed too hard on the lower knife table. At this point too therefore scratch marks cannot be caused.

In the figure of the drawing is a longitudinal dividing shears designed according to the invention, transversely to the cutting edges seen the knife, shown.

'■: _ The shear stand 1 has in a known manner comprises a stationary lower knife table 2 on which the straight lower blade is attached. 3

At the top, the two crankshafts 4 and 5 are mounted in the scissors stand 1, on which two connecting rods 6 and 7, the lower knife carrier 8 is suspended so that it can be raised and lowered, which supports the arcuate upper knife 9 wearing

The crankshafts 4 and 5 and the associated connecting rods 6 and 7 are designed so that the upper knife 9 in the jo Course of each crankshaft rotation a cutting stroke in Executes a so-called roll cutting movement, in the course of which the end 10 of the The upper knife 9 dips into the sheet metal 11 lying on the lower knife slide 2

The sheet 11 is pushed forward with the help of the driver 12 by a section corresponding to the cutting length of the two knives 3 and 8, with the Biech U still in motion when the upper knife 9 with its end 10 in the generated during the previous cutting stroke The end area of the partial longitudinal section is immersed in the sheet metal 11.

So that during this operating state no sliding of the moving plate 11 and the Upper knife 9 can arise, a rolling element is in front of the end 10 of the upper knife 9 on the upper knife carrier 8 13 freely rotatable in the form of a roller, the circumference of which is slightly above the cutting edge of the Upper knife 9 on the upper knife carrier 8 a rolling element 13 in the form of a roller freely rotatably mounted with its circumference protrudes slightly over the cutting edge of the upper knife 9. This roller 13 hits it in each case before the end 10 of the upper knife 9 on the still moving sheet II and presses in the end of the previously created longitudinal section, the severed sheet metal strips on the Upper knife side elastically downwards, while it is still sliding over one another under the roller 13 the sheet 11 and the upper knife 9 is safely avoided.

To ensure that the sheet metal strip located on the lower knife table 2 is pressed too firmly onto the To avoid lower knife table 2 and to prevent scratch marks on the sheet metal there too voj the lower knife 3 at the same height as the roller 13 but opposite this towards the lower knife side offset a roller 14 freely rotatably mounted, the circumference of which is slightly above the cutting edge of the Lower knife 3 protrudes.

This roller 14 acts as a support roller for the sheet 11 and prevents this from moving downwards Roller 13 is pressed too tightly onto the lower blade table 2 or onto the cutting edge of the lower blade 3.

Finally, it should only be mentioned that the two roles 13 and 14 do not interfere with one another, because they viewed across the cutting edges of the knives 3 and 9 in the direction of their bearing axes against each other are arranged offset, to such an extent that they are each behind the knife face.

1 sheet of drawings

Claims (3)

'f patent claims: 1. Slitting shears for rolled sheets, especially for thick sheets, with a roll cutting movement executing, arched upper knife and a fixed, straight lower knife, whereby the Upper knife compared to the lower knife according to the different sheet thicknesses on different Penetration pre-settable is characterized in that before the end of the immersion (10) of the upper knife (9) on the upper knife carrier (8) a rolling element (13) is mounted protrudes slightly over the cutting edge of the upper knife (9). 2. Slitting shears according to claim 1, characterized in that the rolling body is a roller (13) which is freely rotatable about an axis directed transversely to the cutting edge of the upper knife (9). 3. Slitting shears according to claims 1 and 2, characterized in that at the front end of the Lower knife (3) approximately below the roller (13) located on the upper knife carrier (8) has a support roller (14) which protrudes slightly over the cutting edge of the lower blade (3). ok