EP3081355B1 - Cutting device - Google Patents

Description

The present invention relates to a cutting device according to the preamble of claim 1.

In such cutting devices with a so-called "guillotine", a fixed knife is lowered onto the profile to be cut off, wherein the profile is severed. For this purpose, a blade of the knife is attached obliquely to the lowering movement of a knife carrier, which can be moved by means of a drive up and down. Such a device is for example from the DE 201 10 794 U1 known.

In irregular cross sections of a plastic profile with a base body and a protruding from the body approach, as they are usually found in window profiles, it often comes to the situation that the inclined knife when lowering on the plastic profile on the first, on the Base body protruding approach of the plastic profile meets. Since the approach does not rest on the cutting table of the cutter and thus is not supported by the cutting process, therefore, arises when hitting the blade on the plastic profile a compressive force on the approach, which can cause the profile cross-section deformed. A deformation of the profile cross-section often has the consequence that the cut does not occur precisely in the desired cutting plane and the profile must be cut exactly before its further use again.

For profile cross-sections with horizontally protruding over the body approach, it is crucial whether the oblique cut attaches to the free edge of the neck or on the body. If the cut initially starts on the main body and continues in the direction of the projecting shoulder, the deformation of a plastic profile during the cutting process can be minimized.

Plastic profiles are usually extruded. The protruding approach can occur in plastic profiles in the conveying direction of the plastic profile both right and left.

Since the cutting devices are often used directly after an extruder in an extrusion line, the feeding of the profile to be cut is only from one side of the Cutting device possible.

This has the consequence that, depending on which side is the outstanding approach, the orientation of the slanted knife the cutter must be adapted to the plastic profile.

To eliminate this problem suggests the DE 2012 005 943 U1 Before by means of a rotatably mounted table top, the obliquely positioned knife to rotate about an axis parallel to the lowering of the knife axis by 180 °.

This device, which now allows to cut plastic profiles with protruding in the conveying direction of the extruded plastic profile right or left approaches, has a relatively complex construction.

It is therefore an object of the present invention to provide an improved cutting device with which the cutting to length of plastic profiles is possible, which have in the conveying direction of the extruded plastic profile right or left outstanding approaches.

According to the invention the object is achieved by a cutting device comprising a cutting unit with a substantially U-shaped knife carrier can be lowered in the cutting direction with a first and a second leg and a clamping device for clamping a cutting blade in the knife carrier, wherein on each leg of the knife carrier an attachment point to releasably receiving a cutting blade is provided, wherein two attachment points are provided on each leg, wherein in each case an attachment point of the first leg of an attachment point of the second leg is assigned and form a fastening point pair, which is adapted to hold the cutting blade in a predetermined cutting position, and wherein each attachment point pair has a by means of the clamping device displaceable attachment point.

With the help of the cutting device according to the invention, it is possible to hold a cutting blade in two different, with respect to the lowering movement of the knife carrier oblique positions. The slidable by means of the clamping device attachment point of each attachment point pair ensures that the cutting blade is securely clamped in the cutting device.

In a preferred embodiment of a cutting device, the distances of the two attachment points of each attachment point pair are the same, so that one and the same cutting blade can be held and fixed in the two predetermined by the two attachment point pairs cutting positions.

It is also advantageous that each attachment point pair forms a connecting line between the two attachment points and intersect the two connecting lines of the attachment point pairs within the U-shaped blade carrier. Thus, the two attachment point pairs can provide two attachment positions with an inclination angle with respect to the lowering axis of the blade carrier, which have different signs or directions of rotation.

Here, it is further preferred that the attachment points are arranged mirror-symmetrically with respect to the median plane of the knife carrier on the first and the second leg of the knife carrier. Thus, the inclination angles differ in the two mounting positions only in the direction of rotation or in their sign, so that mirror-image plastic profiles can be cut with the same quality.

It is advantageous that each attachment point pair has a displaceable attachment point in the form of a displaceable pin and a non-displaceable attachment point in the form of a rigid bolt.

Preferably, the displaceable pin and the rigid pin have approximately the same diameter, so that it is possible to turn a cutting knife with bores into which the displaceable pin and the rigid pin are insertable. This can lead to a significant increase in the life of a cutting blade.

In a preferred embodiment, the displaceable attachment points of both attachment point pairs can be actuated by means of a common tensioning device. This allows a comparatively simple construction of the cutting device.

In a preferred embodiment, the displaceable attachment point of a first attachment point pair on the first leg of the knife carrier and the displaceable attachment point of a second attachment point pair are provided on the second leg of the knife carrier.

In an alternative embodiment, the displaceable attachment point of a first attachment point pair on a leg of the knife carrier and the displaceable attachment point of a second attachment point pair are provided on the same leg of the knife carrier as the sliding attachment point of the first attachment point pair.

This results in a large number of different clamping devices, by means of which the displaceable pins can be actuated.

Thus, it is preferred that the tensioning device has a lever arrangement and the displaceable attachment point of a first attachment point pair and the displaceable attachment point of a second attachment point pair can be actuated by means of the lever arrangement.

Alternatively, the tensioning device has an eccentric shaft and the displaceable attachment point of a first attachment point pair and the displaceable attachment point of a second attachment point pair can be actuated by means of the eccentric shaft.

In a preferred embodiment, the clamping device holding means for the cutting blade to hold the cutting blade transversely to the cutting direction, in the conveying direction of the profile to be cut.

Fig. 1

einen perspektivischen Ausschnitt einer Schneidvorrichtung gemäß einer ersten Ausführungsform,

Fig. 2

einen Längsquerschnitt durch einen Messerträger der in Fig. 1 dargestellten Schneidvorrichtung,

Fig. 3

eine Draufsicht auf eine Basis des in den Figuren 1 und 2 dargestellten Messerträgers,

Fig. 4

einen perspektivischen Ausschnitt einer Schneidvorrichtung gemäß einer zweiten Ausführungsform,

Fig. 5

einen weiteren perspektivischen Ausschnitt einer Schneidvorrichtung gemäß einer zweiten Ausführungsform,

Fig. 6

einen Querschnitt durch einen Messerträger gemäß der zweiten Ausführungsform,

Fig. 7

einen Teilausschnitt der Schneidvorrichtung gemäß der zweiten Ausführungsform und

Fig. 8

eine Draufsicht auf die Basis des Messerträgers der zweiten Ausführungsform.

Preferred embodiments of the invention will be explained in more detail with reference to the accompanying drawings, in which:

Fig. 1

a perspective section of a cutting device according to a first embodiment,

Fig. 2

a longitudinal cross section through a knife carrier of in Fig. 1 illustrated cutting device,

Fig. 3

a plan view of a base of the in the FIGS. 1 and 2 illustrated knife carrier,

Fig. 4

a perspective section of a cutting device according to a second embodiment,

Fig. 5

a further perspective section of a cutting device according to a second embodiment,

Fig. 6

a cross section through a knife carrier according to the second embodiment,

Fig. 7

a partial section of the cutting device according to the second embodiment and

Fig. 8

a plan view of the base of the knife carrier of the second embodiment.

Fig. 1 shows a section of a cutting device 10, comprising a cutting unit 12 with attached cutting blades 14 and a cutting table 16. In the cutting table 16, a cutting gap 18 is provided.

Although in Fig. 1 as well as further figures shown two cutting blades 14 are shown, so only one of the two knives shown is installed during operation of the cutting device. The two in Fig. 1 illustrated cutting blades are only, as will be explained below, two different cutting positions.

Fig. 1 shows the cutting unit 12 and the cutting table 16 together with a cut plastic profile 19 from the front, ie with a view in the conveying direction of the plastic profile 19. The cutting unit 12 includes a substantially U-shaped lowerable knife carrier 20 with a first leg 22, a second leg 24 and a base 26 (see Fig. 2 ).

The cutting device 10 serves for cutting plastic profiles. Here, the cutting unit 12 is lowered together with a cutting blade 14 in the direction of the cutting table 16. The cutting blade 14 is aligned obliquely with respect to the lowering axis of the cutting unit, preferably at an angle between 45 ° and 75 °, so that the blade 14 inclined with respect to the plane of the cutting table 16 firstly projects into an edge side of the plastic profile 19 lying on the cutting table dips and then cuts through the plastic profile 19. In this case, the cutting blade 14 is guided by the cutting gap 18 down.

As in particular in Fig. 2 it can be seen, two are on the first leg 22 Attachment points 28, 30 and on the second leg 24 has two attachment points 32, 34 are provided. The attachment point 28 of the first leg 22 and the attachment point 32 of the second leg 24 are formed as sliding pins, while the attachment points 30 of the first leg 22 and the attachment point 34 of the second leg 24 are formed as fixed bolts.

The sliding pin 28 of the first leg 22 and the bolt 34 of the second leg 24 form a first attachment point pair. The sliding pin 32 of the second leg 24 and the bolt 30 of the first leg 22 form a second attachment point pair. Each attachment point pair is adapted to hold a cutting blade 14 in a predetermined cutting position.

Each attachment point pair forms a connecting line between the two attachment points 28, 34 and 32, 30, wherein the two connecting lines of the attachment point pairs intersect within the U-shaped blade carrier 20.

Thus, a cutting blade 14 can be mounted in two different cutting positions on the knife carrier 20, wherein the cutting blade is deflected in a first cutting position relative to a horizontal position in the clockwise direction and in a second cutting position relative to a horizontal position in the counterclockwise direction.

The two in Fig. 1 illustrated knife 14 illustrate the two positions in which a knife 14 can be held by means of the first attachment point pair or the second attachment point pair.

The distances of the displaceable pin 28 and the bolt 34 and the distance between the displaceable pin 32 and the bolt 30 of the second fastening point pair are the same, so that one and the same cutting blade 14 can be held and fastened in both cutting positions.

In this case, the cutting blade 14 bores, which are suitable, can pass through both the movable pin 28, 32 and by the bolts 34, 30. Preferably, the slidable pins 28, 32 and the bolts 34, 30 have approximately the same diameter.

The attachment points 28, 30, 32 and 34 lie in a plane parallel to Cutting plane, so that attached to the attachment points 28, 34 and 30, 32 cutting blade 14 interact without further changes to the cutting device 12 with the cutting gap 18, ie, can dive into this.

The fastening points 28, 30, 32, 34 are aligned mirror-symmetrically with respect to the center plane of the measuring carrier 20, in particular with respect to the inner sides of the two legs 22, 24. As a result, regardless of the cutting position in which they are attached, the cutting blades 14 strike the plastic profile 19 to be cut at the same angle.

The cutting device 10 further comprises, for example, a hydraulically or pneumatically actuable clamping device 36 with two cylinders 38a, 38b above the knife carrier 20, each acting on a free end of a rotatably mounted lever arm 40a, 40b. The rotatable lever arms 40a, 40b are aligned along the first leg 22 and along the second leg 24 and are actuated synchronously by means of the tensioning device 36.

Each rotatable lever arm 40a, 40b is connected to a sliding pin 28, 32.

Furthermore, a Messerfixiervorrichtung 42 is provided (see Fig. 3 ). The Messerfixiervorrichtung 42 comprises two fixing units 44 a, 44 b, which are each arranged on a leg 22, 24. Each fixing unit 44a, 44b in turn comprises a cylinder 46a, 46b, a linkage 48a, 48b pivotally connected to the cylinder 46a, 46b, on which is rotatably mounted a rotatable rod 50a, 50b, the rotatable rods 50a, 50b being substantially respectively are aligned parallel to the first leg 22 and the second leg 24 of the blade carrier 20.

At the height of the attachment points 28, 30, 32 and 34, each rod 50a, 50b holding elements in the form of retaining flaps 52 (see Fig. 1 ).

If the displaceable pins 28, 32 are in a relaxed, ie unlocked position, the distance between each attachment point pair 28, 34 or 30, 32 is designed to provide a cutting blade 40 with corresponding bores in a first first cutting position formed by the first attachment point pair. in a second formed by the second attachment point pair second cutting position.

When the cutting blade 14 is in the first mounting position, such as in the attachment locations 28 and 34 of the first attachment point pair, the cylinders 38a, 38b are actuated by a control device, not shown, and exert a force on the respective lever arm 40a, 40b, respectively. The lever arms 40a, 40b are pivoted so that the pin 28 and 32 connected to the lever arm 40a and 40b is displaced. As a result, the cutting blade is clamped in its longitudinal axis in the cutting device 10.

Regardless of the cylinders 38a, 38b of the tensioning device 36, but approximately at the same time, the cylinders 46a, 46b of the blade fixing device 42 are actuated by means of the control device, not shown. The cylinders 46a, 46b of the knife fixing device 42 act on the respective linkage 48a, 48b, so that the rods 50a, 50b respectively rotate from their initial position by a predetermined angle to a holding position. As a result, the holding flaps 52 arranged on the rods 50a, 50b are directed onto the cutting blade 14 from outside, so that the cutting blade 14 is held securely in the pin 28 or pin 34.

The distance between the first leg 22 and the second leg 24 and the retaining flaps 52 in the holding position is smaller than the thickness of the cutting blade 14. The cutting blade 14 is intended by means of the retaining flaps 52 against displacement perpendicular to the cutting plane and thus against falling out of the Attachment points 28, 34 are secured. Above all, however, the retaining flaps 52 serve to exert a pressure on the cutting blade 14 in order to stabilize the blade torsionally rigid in the blade carrier 20.

To remove the cutting blade 14 again from its cutting position, the rods 50a, 50b of the blade fixing device 42 are rotated to the starting position, in this case the retaining flaps 52 are pivoted away from the attachment points 28 and 34, so that the cutting blade 14 is accessible. The retaining flaps 52 must thus be pivoted at an angle which makes it possible to remove the cutting blade 14 again from the fastening points 28 and 34.

Regardless of the pivotal movement of the rods 50a, 50b, the lever arms 40a and 40b are pivoted back to their relaxed position, so that the sliding pin 28 can return to its relaxed position, in which removal of the cutting blade 14 from the two attachment points 28, 34 possible is.

Now the cutting blade 14 can be exchanged for a new cutting blade, turned or brought into the second cutting position.

In order to bring the cutting blade into the second cutting position in which it is mounted in the sliding pin 32 and the bolt 30, the tensioning device 36 is actuated in the same manner as described above. The pin 32 of the second attachment point pair is displaced by means of the lever arm 40b to clamp the cutting blade 14, and the retaining flaps 52 on the rotatable rods 50a, 50b are pivoted to securely hold the cutting blade 14 in the second cutting position.

In the illustrated embodiment, the cylinders 38a, 38b are activated by means of a common actuating unit, so that the lever arms 40a, 40b and thus the pins 28 and 32 are actuated synchronously. This means that when clamping a knife and the pin 32 or 28 is actuated, which carries no knife.

However, in another embodiment, the cylinders 38a, 38b can also be actuated independently of each other, so that only the pin 28 or 32 which carries the blade is displaced in each case.

The FIGS. 4 to 8 show a second embodiment of a cutting device 110 with a cutting unit 112, which has a knife carrier 120, in which the bolts 128, 130 on the first leg 122 and the sliding pins 132, 134 are arranged on the second leg 124. The bolt 128 and the sliding pin 134 form a first fastening point pair and thus provide a first cutting position ready. The bolt 130 and the sliding pin 132 form a second fastening point pair and thus provide a second cutting position.

The distance of the bolt 128 and the sliding pin 134 of the first attachment point pair corresponds to the distance of the bolt 130 and the displaceable pin 132 of the second attachment point pair to fix one and the same cutting blade in both cutting positions.

Furthermore, the attachment points 128, 130, 132, 134 with respect to the center plane of the measuring carrier 120, in particular with respect to the inner sides of the two legs 122, 124 are mirror-symmetrical and lie in a plane parallel to the cutting plane.

The tensioning device 136, by means of which the two displaceable pins 132, 134 are displaceable, comprises a cylinder 138 which is arranged along the leg 124, on which the displaceable pins 132, 134 are provided, a joint 158 and one with the joint 158 connected eccentric shaft 160.

The displaceable pins 132, 134 are rotatably mounted, wherein at each displaceable pin 132, 134 perpendicular to its axis of rotation a pin 162, 164 is arranged, which interacts with the eccentric shaft 160.

Furthermore, a Messerfixiervorrichtung 142 is provided. Knife fixing device 142 includes two fixing units 144a, 144b each having a cylinder 146a, 146b, a rotatable linkage 148a, 148b, and a rotatable rod 150a, 150b disposed perpendicular to rotatable linkage 148a, 148b, with rotatable rods 150a, 150b respectively substantially are aligned parallel to the first leg 122 and the second leg 124 of the blade carrier 120.

The two cylinders 146a, 146b are arranged above the base 126 of the knife carrier along the base 126.

At the height of the attachment points 128, 130, 132 and 134, each rod 150a, 150b retaining elements in the form of retaining flaps 152.

If the cutting blade is arranged in its desired cutting position, the clamping device 136 is actuated by means of a control device, not shown, and thereby the cylinder 138 is activated. The cylinder 138 acts on the hinge 158 and rotates the eccentric shaft 160 so that the pins 162, 164 move the sliding pins 132, 134 upwardly and downwardly, respectively, in the direction of the axis of the legs. A cutting knife located in the first or second cutting position is thus clamped.

Independently of the cylinder 138 of the tensioning device 136, but approximately at the same time, the cylinders 146a, 146b of the blade fixing device 142 are actuated by means of the control device, not shown. The cylinders 146a, 146b of the knife fixing device 142 act on the respective linkage 148a, 148b, so that the rods 150a, 150b each rotate from its initial position by a predetermined angle in the holding position in which the cutting blade 114 securely in the pin 132, 134th or is held in the bolt 128 and 130, respectively.

To remove the cutting blade from the cutting device 112 is moved in the reverse direction.

Instead of a hydraulically or pneumatically operated clamping or knife fixing device, it is also possible to use clamping or knife fixing devices which are electrically actuated in other ways, for example.

Claims (12)

1. Cutting device comprising a cutting unit having a substantially U-shaped blade carrier (20; 120), which can be lowered in the cutting direction (12; 112) and has a first and a second leg (22, 24; 122, 124), and a clamping device for clamping a cutting blade (14; 114) in the blade carrier (20; 120), a fastening point (28, 30, 32, 34; 128, 130, 132, 134) for detachably receiving a cutting blade (14; 114) being provided on each leg (22, 24; 122, 124) of the blade carrier (20; 120),
   characterised in that two fastening points (28, 30, 32, 34; 128, 130, 132, 134) are provided on each leg (22, 24; 122, 124), a fastening point (28, 30; 128, 130) of the first leg (22; 122) being associated with a fastening point (32, 34; 132, 134) of the second leg (24; 124), respectively, and forming a pair of fastening points which is suitable for holding a cutting blade (14; 114) in a predefined cutting position, each pair of fastening points comprising a fastening point (28, 32; 132, 134) that can be displaced by means of the clamping device.
2. Cutting device according to claim 1, characterised in that the distances between the two fastening points (28, 30, 32, 34; 128, 130, 132, 134) of each pair of fastening points are equal.
3. Cutting device according to either claim 1 or claim 2, characterised in that each pair of fastening points forms a connecting line between the two fastening points and the two connecting lines of the pairs of fastening points intersect inside the U-shaped blade carrier (20; 120).
4. Cutting device according to any of the preceding claims, characterised in that the fastening points (28, 30, 32, 34; 128, 130, 132, 134) are arranged on the first and the second leg (22, 24; 122, 124) of the blade carrier (20; 120) so as to be mirror symmetrical with respect to the central plane of the blade carrier (20; 120).
5. Cutting device according to any of the preceding claims, characterised in that each pair of fastening points comprises a displaceable fastening point (28, 32; 132, 134) in the form of a displaceable peg and a non-displaceable fastening point (30, 34; 128, 132) in the form of a rigid pin.
6. Cutting device according to any of the preceding claims, characterised in that the displaceable fastening points (28, 32; 132, 134) of both pairs of fastening points can be actuated by means of a common clamping device.
7. Cutting device according to any of the preceding claims, characterised in that the displaceable fastening point (28) of a first pair of fastening points is provided on the first leg (22) of the blade carrier (20) and the displaceable fastening point (32) of a second pair of fastening points is provided on the second leg (24) of the blade carrier (20).
8. Cutting device according to any of claims 1 to 6, characterised in that the displaceable fastening point (132) of a first pair of fastening points is provided on a leg (124) of the blade carrier (120) and the displaceable fastening point (134) of a second pair of fastening points is provided on the same leg (124) of the blade carrier (120) as the displaceable fastening point (132) of the first pair of fastening points.
9. Cutting device according to any of the preceding claims, characterised in that the clamping device (36) comprises a lever arrangement (38) and the displaceable fastening point (28) of a first pair of fastening points and the displaceable fastening point (32) of a second pair of fastening points can be actuated by means of the lever arrangement (38).
10. Cutting device according to any of the preceding claims, characterised in that the clamping device comprises an eccentric shaft (160) and the displaceable fastening point (134) of a first pair of fastening points and the displaceable fastening point (132) of a second pair or fastening points can be actuated by means of the eccentric shaft (160).
11. Cutting device according to any of the preceding claims, characterised in that the clamping device comprises holding means (52; 152) for the cutting blade (14; 114).
12. Cutting device according to any of the preceding claims, comprising a cutting blade having at least two holes, the fastening points (28, 30, 32, 34; 128, 130, 132, 134) of a pair of fastening points passing through the holes in the cutting blade.

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