EP0935517B1 - A knife holder for a wrapper cutter with a hand guard - Google Patents

Description

The invention relates to a knife holder for one in one Cutter head rotatably mounted circular knife for slitting of material webs, especially paper material webs or plastic film, the knife holder with a Hand protection is provided.

By longitudinally cutting material webs using circular knives, who work according to the paper cutting system are out the originally wide material webs narrow material strips generated, the width of each according to the corresponding Use case aimed. To narrow tapes as possible or creating stripes, it is necessary that the on one Knife bars to be set next to each other at an appropriate distance Circular knife holder the smallest possible width have the minimum possible cutting width is essentially determined. For occupational safety reasons it is particularly important to help the worker with adjustment work protect against injuries from the circular knife, it being known to use a circular knife with an optionally adjustable Cover. Depending on the version of the cover the problem arises that the width of the knife holder is enlarged, making the minimum possible Cutting width decreases.

From DE-PS 37 12 078 is a knife holder for slitter machines known that has a hand protection that on the side facing the counter knife by at least a can segment is supplemented by a separate piston-cylinder unit can be operated with the piston-cylinder unit is connected in series. In the counter knife the raised position of the circular knife is the can segment closed by spring force. During the lowering movement the circular knife are both piston-cylinder units pressurized with the pressure medium so that the can segment in swings in the hand protection and the cutting edge of the circular knife releases. Such a knife holder proves to be disadvantageous in that in addition to the high construction costs for a additional piston-cylinder unit a larger width the knife holder is necessary.

EP-A-0 562 454 shows a similar arrangement with two parts Protective hood, the counter knife facing as Can segment designed and provided with a slot Part of the protective hood is vertically displaceable. Also the can segment is connected to a separate piston-cylinder unit emotional. In the off position of the Circular knife is the can segment by a closing spring in Closed position held and when lowering over the piston withdrawn so that the cutting edge of the circular knife through the Slots can pass through. Such a trained one Hand protection is due to the multi-part structure and the necessary complicated adjustment mechanism complex and susceptible to interference. This document is used as a description of the closest state of the art and disclosed a knife holder for a rotatable in a knife head stored circular knife for slitting material webs, with a base body that can be attached to a cutter bar, where the cutter head between a rest position and a cutting position back and forth is mounted, and with a circular knife covering at least part of its circumference Protective hood that can be moved relative to the circular knife (2) is mounted so that in the cutting position area engaged with a lower knife Cutting edge exposed and in the rest position Cutting edge is partially covered by the protective hood.

EP-A-0 333 001 shows a knife holder with a protective hood as hand protection, which is fixed to the main body of the knife holder is attached and in the raised position of the Circular knife completely covered this. When lowering the The circular knife extends against the counter knife the fixed protective hood.

DE-U-90 12 926 also shows a knife holder for slitting machines, with the circular knife on the side and on the side facing away from the counter knife with a firm hand guard is surrounded, and the cutting area of the knife through a movable segment is covered, which is also opened by a complex drive device and is closed.

The invention is therefore based on the object of a knife holder to create for circular knives with a limited space good functional safety for hand protection in one construction as simple as possible.

The object is achieved by a knife holder for a rotatably mounted in a cutter head Circular knife for the longest cutting of material webs, with one, on a cutter bar attachable body on which the Cutter head over a crossbar between a rest position and a cutting position is mounted to move back and forth, and with a circular knife over at least part of his Circumferential protective hood that is relative to the circular knife is movably mounted so that in the cutting position area engaged with a lower knife The cutting edge is exposed and in the rest position the cutting edge of the protective hood is at least protruded laterally, and with a Return spring between the protective hood and the crossbar is arranged so that it covers the protective cover the cutting position of the circular knife in one the cutting edge holding the circular knife releasing working position, and that in the rest position of the circular knife through the protective hood a stop arranged on the base body in a protective position is pressed, in which the circular knife through the protective hood is covered. The advantage of a design according to the invention Knife holder is that in the rest position of the Knife head of the worker from injuries from the circular knife edge is protected, under the rest position of the Knife head understood in the sense of this invention, the position in which the circular knife of the assigned lower knife is lifted off. In the rest position of the circular knife the worker can adjust the knife holder and / or the Make circular knife or a web of material in the gap insert between the raised circular knife and the lower knife. In the rest position, the circular knife edge is replaced by a protrudes in a protective position, so that injuries to the worker on the circular knife are prevented, being under the protective position of the protective hood in the sense the invention is understood the position in which the Protective hood is moved in the direction of the lower knife and the Circular knife edge completely towered over. The return spring, that acts between the crossbar and the protective hood for example as a torsion-compression or tension spring be trained.

The protective hood designed in one piece according to the invention enables compared to the known prior art simple and reliable protection of the worker against injuries through the circular knife edge. Because the only one-piece Protective hood must be moved, the more elaborate Constructions designed to protect against the circular knife a segment that can be moved in addition to a rigid protective hood need that are moved via separate drives got to. The simple protective function of the protective hood is thereby ensures that as soon as the cutter head from the lower cutter the protective hood is lifted by means of the on the base body arranged stop automatically pressed into the protective position is so that in the rest position of the cutter head Circular knife edge is completely covered. The one on the body arranged stop pushes the protective hood in the direction of the lower knife. When the cutter head is in the cutting position extends the protective hood by means of a return spring, between the protective hood and the crossbar appears pressed into a working position and held there.

In an advantageous embodiment of the invention, that the protective hood can be pivoted in the plane of the circular knife is stored. Around the protective cover in the plane of the circular knife is pivoted between the crossbeam and Protective hood acting bearing element is provided around which the protective hood is pivotable so that in the working position the protective hood at an angle to the protective position is pivoted.

In a further advantageous embodiment of the invention provided that the protective cover slidably to the circular knife is stored. One slidably mounted to the circular knife Protective hood is stored so that the protective hood is translational in the direction of the lifting and lowering movement of the cutter head is movably mounted. Storage of the protective hood can be done, for example, by bolts with the Protective hood are connected and in at least one in the Traverse arranged elongated hole can be performed. Is expedient it if one on both sides of a circular knife axis Elongated hole is arranged, which is in its length in the direction the lifting and lowering movement extends. It is still possible that the bolts are connected to the crossbar and guided in an elongated hole arranged in the protective hood become. It is also possible that the traverse has a groove has a slot nut connected to the protective hood to be led.

In a particularly advantageous embodiment of the invention provided that at least one between the traverse and the Movable protective hood acting guide element is provided is. The advantage of one between the traverse and the protective hood acting guide element is that in particular pivoted in the plane of the circular knife Protective cover that is also connected to the crossbar, which results in better storage and guidance of the protective hood results. A guide element prevents in particular lateral deflection of the protective hood against the plane of the Circular blade. A guide element connected to the protective hood can, for example, in a arranged on the crossbar Engage slot or a groove, the slot or the groove expediently has the shape of an arc of a circle, that of the guide element during a pivoting movement the protective hood is painted over.

In an expedient embodiment of the invention, that the stop is adjustable. Adjustable by one trained stop, it is possible to adapt it so that depending on the application, the optimal protective and / or working position the protective hood is adjustable.

In an advantageous embodiment of the invention, that the protective hood is approximately circular, the outer diameter of the protective hood is larger than that Diameter of the circular knife, so that in the protective position the cutting edge of the circular knife is completely covered.

In a further advantageous embodiment of the invention provided that a vertical to the circular knife level on the protective hood angled edge is arranged, which is at least extends over a portion of the circumference of the protective hood. By the one angled vertically to the circular knife level Edge is achieved that the circular knife edge on the one hand is covered at least over a portion of the circumference and on the other hand, one side of the circular knife is accessible remains to change the circular knife from this side and / or to be able to adjust. In particular, it is provided that on the side facing the lower knife Protective hood no edge is arranged so that the protective hood in the working area of the circular knife only from one parallel to the Part of the protective hood that extends at the knife level in the rest position is covered.

In an expedient embodiment of the invention, that the angled edge extends over the full circumference of the Circular knife extends and in its assigned to the cutting position Area a slot-shaped opening for the circular knife edge having. Because the angled edge in its area assigned to the cutting position has slot-shaped opening, it is achieved that at a Movement of the protective hood into the working position of the circular knife edge pass through the slit-shaped opening can. When the protective hood is in the protective position, is the cutting edge through the angled edge with the slot-shaped opening covered, causing injury to the Avoid worker.

Fig. 1

eine seitliche Ansicht eines Messerhalters für Kreismesser,

Fig. 2

eine teilweise geschnittene Vorderansicht des Messerhalters gemäß Fig. 1 mit einer ersten Ausführungsform für die Schutzhaube, wobei sich der Messerkopf in der Ruheposition befindet,

Fig. 3

eine teilweise geschnittene Vorderansicht des Messerhalters gemäß Fig. 1 mit einer weiteren Ausführungsform für die Schutzhaube, wobei sich der Messerkopf in der Schneidposition befindet.

The invention is explained in more detail below on the basis of the schematic drawings of an exemplary embodiment. Show it:

Fig. 1

a side view of a knife holder for circular knives,

Fig. 2

2 shows a partially sectioned front view of the knife holder according to FIG. 1 with a first embodiment for the protective hood, the knife head being in the rest position,

Fig. 3

a partially sectioned front view of the knife holder according to FIG. 1 with a further embodiment for the protective hood, the knife head being in the cutting position.

Fig. 1 shows a side view of a knife holder 1 for Circular knife 2 with a base body 3, which is not closer to one knife bar shown by means of clamping means and a Fastening groove 4 can be determined. The base body 3 has at least a guide rod 5, which in the base body 3rd by means of guides via a piston-cylinder unit in the base body is movable.

A cutter head is on the guide rod 5 by means of a cross member 6 7 stored. The cutting edge of the circular knife 2 is in the essentially covered by a protective hood 9 which is pivotable around a bearing element 10 in the plane of the circular knife 2 is stored. The bearing element 10 is in a bore 11 of the protective hood 9 arranged and connected to the cross member 6.

Through the bore 12 provided on the protective hood 9 for The protective hood is suitable for accommodating a storage element 10 for right and left hinges.

If the cutter head 7 is in the cutting position, what is understood by that is that the cutting edge 8 of the circular knife 2 with a Interacting lower knife 13, the protective hood 9 is by means of one acting between the protective hood 9 and the cross member 6 Return spring 17, which is designed as a tension spring in the Working position deflected, causing the cutting edge 8 of the circular knife 2 is released and the protective hood 9 protrudes.

Depending on the setting of one arranged on the base body 3 Stop 14 is when lifting the cutter head 7 from the lower knife 13 in the direction of arrow "X" the protective hood 9 inevitably pressed against the stop 14, so that, approximately inversely proportional to the movement of the cutter head 7, the protective hood 9 in the direction of the arrow "Y" is deflected until at least the circular knife edge 8 the edge of the protective hood is covered, as shown in FIG. 2 is indicated.

Fig. 2 shows a partially sectioned front view of the Knife holder 1 according to FIG. 1 with a guide rod 5 the cross member 6 is connected by means of screws 15, wherein on the traverse 6 the cutter head 7 is mounted and in a Rest position "R" has moved. The fully drawn representation shows the protective hood 9 in the protective position "S", wherein the dashed line depicts the protective hood in shows the working position "A".

The protective hood 9 is in this position by the on the base body 2 adjustable stop 14 in its protective position "S" pressed when the cutter head 7 from the lower cutter 13 is lifted off. Towering in the protective position "S" the edge 19 of the protective hood 9 the cutting edge 8 of the circular knife 2, so that injuries to the worker are avoided.

Fig. 3 shows the knife holder 1 in the cutting position "P". The coverage of the circular knife edge 8 is shown in the Embodiment by a vertical to the circular knife level 8 angled edge 18 which extends over the extends over the entire scope and one in the work area Has slot 16.

When the cutter head 7 is extended in the direction of the lower cutter 13 the stop 14 no longer presses against the Protective hood 9, which due to the spring force of the return spring 17 the protective hood 9 is pivoted into a working position "A" becomes.

When the protective hood 9 is in the working position "A", the circular knife 2 can pass through the opening slot 16, the one that is angled vertically to the circular knife plane Edge 18 is arranged.

Claims (8)

1. Knife holder (1) for a circular knife (2) mounted in a cutter head (7) in such a way that it can rotate, for the purpose of slitting lengths of material, having a base unit (3) which can be attached to a blade rail, on which unit is mounted the cutter head (7) by means of a cross-piece in such a way that it can be moved to and fro between a non-working position (R) and a cutting position (P); and having a safety cover (9) which covers at least part of the circumference of the circular knife (2), the cover being mounted movably relative to the circular knife (2) in such a manner that, when in the cutting position (P), the part of the cutting edge (8) which engages with a lower blade (13) is exposed and, when in the non-working position (R), the safety cover (9) extends at least laterally beyond the cutting edge (8); and having a return spring (17) which is positioned between the safety cover (9) and the cross-piece (6) to operate in such a way that, in the cutting position (P) of the circular knife (2), the safety cover (9) holds it in an operating position (A) which exposes the cutting edge (8) of the circular knife (2), and in the non-working position (R) of the knife (2), the safety cover (9) is pushed into a safety position (S) by a limit stop (14) on the base unit (3), in which position the circular knife (2) is covered by the safety cover (9).
2. Knife holder (1) as in Claim 1, characterised in that the safety cover (9) is mounted in the plane of the circular knife (2) in such a manner that it can be swivelled.
3. Knife holder (1) as in Claim 1, characterised in that the safety cover (9) is mounted in the plane of the circular knife in such a manner that it can be moved in relation to the circular knife (2).
4. Knife holder (1) as in one of Claims 1 to 3, characterised in that there is at least one guide element in operation between the cross-piece (6) and the movable safety cover (9).
5. Knife holder (1) as in one of Claims 1 to 4, characterised in that the limit stop (14) is adjustable.
6. Knife holder (1) as in one of Claims 1 to 5, characterised in that the safety cover (9) is roughly circular in shape, the outer diameter of the safety cover (9) being greater than the diameter of the circular knife (2), so that it extends completely beyond the cutting edge (8) of the knife (2) when in the safety position (S).
7. Knife holder (1) as in one of Claims 1 to 6, characterised in that there is, on the safety cover (9), a rim (18) which is angled vertically in relation to the plane of the knife and which extends over at least part of the circumference of the safety cover (9).
8. Knife holder (1) as in one of Claims 1 to 7, characterised in that the angled rim (18) extends over the entire circumference of the circular knife, and has, in the area corresponding to the cutting position, a slit-shaped opening (16) for the cutting edge (8) of the circular knife.

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