DE1907717B2 - Trimming shears for rolled sheets with transverse knives to cut the edge strips - Google Patents

Description

The invention relates to trimming shears for rolled sheets according to the preamble of the claim. It is based on the Japanese utility model Auslegeschri-ft 2526 '4-1, in one Scissors that can be used for trimming wafer sheets is described, the transverse knife arrangement for severing the hem strips a so-called scissors is. Since the pivot axis of the pivot lever carrying the upper transverse knife is approximately parallel to runs along the long knives, it is to be expected with certainty that the upper transverse knife on the return stroke after the hem strip cut has been made, the cutting edge of the still on the chest surface Sheet metal hanging seam strip upwards and bends upwards. Another feed step this can make the sheet metal impossible.

The invention is based on the object of designing the transverse knife arrangement so that after it has taken place Quermesserschniu a kind of knife retraction is effective, through which the upper cross knife in the Upward gear comes free from the cut edge of the hem strip, so that the next sheet feed the seam strip can pass the scissor opening of the cross knife unhindered. This task is achieved by the means described in the characterizing part of the claim.

In the drawing, a trimmer according to the invention is shown in one embodiment, namely shows

F i g. 1 is a partial front view,

F i g. 2 shows a vertical section through the transverse knife arrangement according to the line IT-II in Fig. 1 and

F i g. 3 shows a section along the line III-III in FIG Fig. 2.

The most important parts of the trimming shears are shown in FIG. 1 of the Scherensländer 10 with lower beam 11, the pivotable upper knife carrier 12 with the upper knife 13 and the one arranged on the outlet side Cross knife arrangement with the Schvyenk lever 24 for the upper cross knife 15 and the fixed lower one Cross knife 16, which is arranged well below the upper edge 17 of the lower long knife 18 a.

The direction of advance of the sheet is indicated by arrow 20. Fig. 1 reveals the inclined cutting plane of the transverse knife arrangement 14 to 16, whereby the knife face 15 α of the upper transverse knife 15 during the return stroke comes free from the cut surface of a hem strip still hanging on the sheet metal, when this comes up after a pushed-through piece of the hem strip is cut springs back. The cut-off seam strips fall onto a chute 21 which conveys the seam strips onto the scrap transport located below the scissors.

In the section according to FIG. 2 you can see a double-armed Swivel lever 24 with the knife saddle 25 for the upper transverse knife 15 and the lower transverse knife 16. The pivot lever is mounted on a pivot axis 26 which is parallel to the Langmesseru 13, 18 runs according to FIG. 3, however, is arranged inclined in the scissors frame 10, namely in the direction of the sheet feeder 20 inclined downwards to the inclined position of the sectional plane shown in FIG Set cross knife 15 and 16.

Since, according to the invention, the pivot axis 26 is below the cutting edge of the lower long knife 18 is, describes the outermost tip of the upper transverse knife 15 when cutting a circular arc 27, which in the Distance from the trimmed edge of the sheet 30 runs. The upper transverse knife 15 thus needs not to be withdrawn even in the horizontal direction during the return stroke, as well as yourself the cutting area of the two transverse knives can be seen in the vertical projection of the trimmed sheet 30 can extend.

The rear end of the double-armed pivot lever 24 is forked and carries a pivot pin 28, to which a pull rod 40 is connected via a spherical sleeve 29. The pull rod 40 is actuated by a large eccentric 42 of the crankshaft 41, also below Interposition of a spherical sleeve 43.

The eccentric 42 is so that the upper transverse knife 15 is separated from the sheet metal 30 and up to the level of the lower transverse knife 16, which is pressed downwardly, begins to cut off the seam strip 31. The direction of rotation of the eccentric 42 is shown in FIG. 2 indicated by an arrow. The crankshaft 41 is otherwise the main crankshaft, which also actuates the pivotable knife carrier 12.

The mode of operation of the trimmer according to the invention is as follows:

When a sheet metal 30 is placed between the trimming knives 13 and 18 through the drive rollers, not shown is advanced, the drive of the scissors is switched on, so that the upper long knife 13 downwards goes and cuts a seam strip 31. As shown in FIG. 1 can be seen, is the cutting edge of the Upper long knife 13 curved at the inlet end, since this cutting edge in the bottom dead center of the knife carrier 12 must emerge from the sheet metal cross-section. The drives for the knife carrier 12 and the transverse knife 15 are angularly offset from one another in such a way that the upper transverse knife 15 later is cut as the upper long knife 13, but the hem strip 31 is still during the hem

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Cut off. When both the knife carrier 12 and the pivot lever 24 decrease the upper transverse knife 15 overtakes the clean long knife 13 because of the considerably greater eccentricity of the eccentric 42 of the scrap knife arrangement compared to the eccentric, not shown, of the trimming knife drive. This will get the upper one Cross knife 15 quickly in an upper dead center position, in which the hem strip 31 hanging on the sheet metal 30, although it has sprung back somewhat to the level of the sheet metal 30 is not disabled. When a yoishub step is finished, is the pivot lever, 1! already passed through its top dead center position and approaches the shown gate position.

In addition 1 Blait drawings

Claims (1)

Claim: Trimming shears for waJzbleche with a pair of long knives for trimming the edge of the sheet and transverse knives for cutting off those that have already been separated from the sheet but are still on the sheet hanging edge strips, whereby the upper transverse knife has its own drive, the cutting edge of the lower transverse knife is lower than the cutting edge of the fixed lower long knife and the upper transverse knife is carried by a pivot lever mounted on one below the Arranged cutting edge of the lower long knife, running approximately parallel to the long knife The pivot axis is mounted, characterized in that the pivot axis (26) of the pivot lever (24) is inclined downward in the feed direction of the sheet metal (30) such that that the upper transverse knife (15) is guided in a plane deviating from the vertical and the knife break (15 a) of the cross knife forms an angle of more than 90 ° with the horizontal.