EP0394937B1 - Rotating cutter for paper cutting apparatus - Google Patents

Abstract

In a rotating cutter for paper cutting apparatus, in particular for multi-layered individual paper products, having a round basic body from whose conical rear face lying opposite the cutting plane adjustable blades or the like project, the blades are locked in such a way as to be adjustable about a pivot. <IMAGE>

Description

The invention relates to a cutting knife for rotary cutting systems for paper, in particular multi-layer, isolated paper products conveyed in scale formation with a round base body, from the conical rear surface of which is opposite the cutting plane running perpendicular to the axis of rotation and which is adjustable in several cutting positions, knives, blades or the like. protrude, which are adjustable in the direction of the cutting plane and lockable in the different cutting positions.

Such a cutting knife is known from DE-OS 37 19 721. The individual blades are essentially adjustable in the radial direction and can be resharpened in such a way that the same cutting radius is achieved after adjusting the blade. Although the same blades can be used several times in this known cutting knife, the blades must be re-sharpened after each adjustment.

The invention has for its object to the shape of the blades or knives in the new cutting position take into account and enable the adjustment without changing the one connection point with the base body.

The object is achieved in that the blades, knives or the like lying with their ground cutting surfaces in the cutting plane. are rotatable in the recesses in the rear surface and can be locked in several positions in order to rotate perpendicular to the conical rear surface of the base body.

A cutting knife is known from FR-PS 1 427 910, in which the round blades can be locked in different cutting positions. However, these round blades lie in the cutting plane, so that the cutting surfaces point to the rear side of the base body; the round cutting knives are each locked by holding screws that can be inserted from the cutting surface.

According to a preferred embodiment of the invention, the blades or the like. designed as discs with a round cut. A modified embodiment of the invention is that the blades or the like. are designed as plate-like polygons and all sides of the polygons have cutting edges or are designed as rounded bulges of a round disc; the blades or the like can be adjustable in polygonal recesses in the base body. In all of the above-mentioned embodiments, the blades are reground or the like. only after the latter become completely unusable.

Another modified embodiment of the invention is that the blades or the like. are formed like a board, are adjustable in approximately wedge-shaped recesses and are connected to the base body by way of their pivot and one pin each; The base body expediently has the like for the adjustable locking of the board-like blades. each part-circular recesses.

A further expedient development of the invention is that the blades or the like. on the conical back surface of the base body, e.g. are covered with a protective ring; the protective ring preferably has at least the width of the blades or the like. on.

Another modification of the invention is that the cutting edges of the blades or the like. enclose an angle of 6 - 12 °, preferably 8 °, with the respective tangent of the base body. The blades can consist of a material that differs from the base body and a specially hardened steel. It has proven to be particularly useful if all cutting surfaces or edges of the blades or the like. are sanded before insertion.

Fig. 1

eine Teilansicht auf die Rückfläche eines Schneidmessers nach einer Ausführungsform der Erfindung;

Fig. 2

eine Teilansicht auf eine zweite Ausführungsform der Erfindung in ähnlicher Darstellung;

Fig. 3

eine Teilansicht auf eine dritte Ausführungsform der Erfindung in ähnlicher Darstellung;

Fig. 4

eine Teilansicht einer vierten Ausführungsform der Erfindung in ähnlicher Darstellung;

Fig. 5

eine Teilansicht auf eine fünfte Ausführungsform der Erfindung in ähnlicher Darstellung;

Fig. 6

eine Teilansicht auf eine sechste Ausführungsform der Erfindung in ähnlicher Darstellung und

Fig. 7

einen Schnitt gemäß Linie 7-7 in Fig. 1.

For example, embodiments of the invention are shown in the drawing; they are described in more detail below. It shows:

Fig. 1

a partial view of the rear surface of a cutting knife according to an embodiment of the invention;

Fig. 2

a partial view of a second embodiment of the invention in a similar representation;

Fig. 3

a partial view of a third embodiment of the invention in a similar representation;

Fig. 4

a partial view of a fourth embodiment of the invention in a similar representation;

Fig. 5

a partial view of a fifth embodiment of the invention in a similar representation;

Fig. 6

a partial view of a sixth embodiment of the invention in a similar representation and

Fig. 7

a section along line 7-7 in Fig. 1st

In all the embodiments described below, the cutting knife consists of a base body 1 and blades 2 which can be locked thereon. Such cutting knives are used in rotary cutting systems, e.g. used for paper products or signatures in scale formation. These isolated paper products are held together on both sides of the cutting knife by press belts.

As can be seen from FIG. 7, the base body 1 is provided with a central opening 3 for placement on a shaft. Furthermore, the base body has bores 4 for attachment to a holder. While the base body 1 is of equal thickness in its central region, its edges run from the edge 5 to be conical or approximately conical. Recesses 10 are provided within the tapered edge, which are round in the present case and have approximately the depth of the blades 2 'designed as disks, each with a circular grinding 11. The blades are conical in cross-section and, on the one hand, are bolt-like in the middle Connection to the base body 1 and on the other hand connected to a protective body 14 described in more detail.

As can be seen from FIG. 1, each disc 2 'has, in addition to the central bore 12, six further holes 15 which are distributed uniformly over the circumference, but at a distance from the edge thereof. The respective radially inner hole 15 'receives a screw bolt or another connecting means and thus locks the disc 2' in the respective position. The protective ring 14 is connected to the base body 1 by a further screw 16 and is otherwise not shown in FIGS. 1 to 6.

Markings 20 are provided on the back of the disk 2 ', each of which delimit a cutting area. After a cutting area has worn out, the disk is then screwed into the next marked section and locked in this position.

The disks 2 '- like all the other embodiments of the blades described below - are about 3-5 mm, preferably 4 mm, thick or thick. The base body can have a diameter of 20-45 mm, and depending on the diameter of the base body, the number of blades or disks can be increased. It is also not necessary that between the recesses a larger distance 21 must be provided for the blades; rather, this distance can also be practically zero.

As indicated by the arrows 22 and 23, the embodiment of the cutting knife according to FIG. 1 can be used in both directions of rotation.

In the embodiment of a similar design of the base body 1 shown in FIG. 2, a hexagonal shape of the blade 2 ″ is provided; the respective cutting edges 30 are of equal length, the rear side of the disc 2 being conical in dashed lines in cross section, so that the one side which serves as the cutting edge has a e.g. occupies the position shown in Fig. 2. The recess 31 for receiving the hexagonal disc 2 "is adapted in the present case to the angular shape of the disc, so that when the disc 2" is adjusted, it must be lifted out of the recess and brought into a different cutting position.

As in the present case, in all other embodiments the cutting plane 32 is formed by the end face of the cutting knife or base body 1 and continues flush through the conical design of the respective blade up to the actual free cutting edge.

While the embodiments according to FIGS. 1, 2 and the embodiment described below according to FIGS. 5 and 6 are basically ground all around, i.e. regrinding of these blades is omitted, in the embodiments according to FIGS. 3 and 4 a board-like blade 40 and 41 is used provided the parallel side faces has and is also 3 - 5 mm, preferably 4 mm, thick.

The blades 40 and 41 must be reground after each adjustment. In Fig. 3 the blade is shown on the left in the initial position; it is held in a rounded slot via the pin 41 and rotates about the pivot pin 42 if an adjustment is made. An adjustment in the direction of arrow 43 of the respective blade 40 is infinitely possible and can be adapted to the grinding requirements.

The blade 40 is adjustable in a wedge-shaped recess 45, the respective edges 46 and 47 of which limit the possibility of adjusting the blade 40.

In the similar embodiment according to FIG. 4, the blade can be adjusted about a pivot pin 51 in the direction of the arrow 50, the second locking of the blade 41 via the hole 52 in a rounded slot 53 of the base body 1 being possible. The recess 54 for the adjustable reception of the blade 41 is adapted to the possibility of adjustment, so that the free edge 55 of the recess runs obliquely, ie approximately wedge-shaped, and thus merges into a section 56 which extends approximately radially. The opposite edges 57 and 58 of the recess 54 are formed accordingly.

The embodiment of the blades 2 and 3 'shown in FIG. 5 is similar to the embodiment according to FIG. 1, but the individual cut edge sections are rounded outwards and thus each result in a larger cutting surface. In this case too, the disc is 2 ''' ground in each case so that an adjustment in the recess 60 is possible six times, that is to say practically six cutting edges are provided. The disc 2 ‴ is locked on the one hand at the center of rotation 61 and then in each case via the one radially inner hole 62.

While the jagged disc 65 is locked in the same way as described in connection with FIGS. 1, 2 and 5, the free edge of the disc 65 is provided with asymmetrically shaped saw teeth 66; the cutting direction is indicated by arrow 67. In the present case as well, of course, the cutting edge 66 lies in the plane 33 of the end face of the base body 1 and the disk 65 is each conical in cross section.

Claims (11)

1. Cutter for rotary cutting installations for paper, especially multi-layer paper products advanced in overlapping formation, comprising a round body (1), from the conical rear surface (5) of which, opposite the cutting plane extending perpendicularly to the axis of rotation, project knives, blades (2,2',2'',40,41,2''',65) or the like which are adjustable into a plurality of cutting positions, wherein said knives, blades or the like are adjustable in the direction of the cutting plane and can be locked in the different cutting positions, characterised in that the knives, blades (2,2',2'',2''',40,41,65) or the like positioned with their ground cutting surfaces (30,66) in the cutting plane are mounted to rotate about axes of rotation extending perpendicularly to the conical rear surface of the body (1) in recesses (10,31,44,45,54,60) in the rear surface and can be locked in a plurality of positions.
2. Cutter according to claim 1, characterised in that the blades or the like are formed as discs (2') with cylindrical grinding (Figure 1).
3. Cutter according to claim 1, characterised in that the blades or the like are in the form of plate-shaped polygons (2'',65) and all of the sides of the polygon have cutting edges (30,66) or are in the form of rounded protuberances of a round disc (Figures 2,5,6).
4. Cutter according to claim 3, characterised in that the blades (2'') or the like are adjustably held in polygonal recesses (31) in the body (1).
5. Cutter according to claim 1, characterised in that the blades (40,41) or the like are in the form of boards, are adjustable in substantially wedge-shaped recesses (44,54) and are connected to the body (1) via their pivot pins (42, 52) and a further pin (41,51).
6. Cutter according to claim 5, characterised in that the body (1) has part-circular recesses (45,54) for adjustable locking of the board-shaped blades (40,41) or the like.
7. Cutter according to one of claims 1 to 6,, characterised in that the blades (2,2',2'',2''',40,41,65) or the like are covered on the conical rear surface of the body (1), eg with a protective ring (14).
8. Cutter according to claim 7, characterised in that the protective ring (14) has at least the width of the blades (2,2',2'',2''',40,41,65) or the like.
9. Cutter according to one of claims 3 to 8, characterised in that the cutting edges (30,66) of the blades (2'',40,41,65) or the like subtend an angle of 6-12°, preferably 8°, with the respective tangent of the body (1).
10. Cutter according to one of claims 1 to 9, characterised in that the blades (2,2',2'',2''',40,41,65) or the like consist of a material different from that of the body (1) and a specially hardened steel.
11. Cutter according to one of claims 1 to 10, characterised in that all of the cutting surfaces or edges of the blades or the like are ground before insertion.

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