EP3581508B1 - Separating device for straps - Google Patents

Description

The invention relates to a severing device for strapping, with a movable pressure element, furthermore with a foot with a pushing edge for the strapping that can be fixed between the foot and the pressure element, and with a cutting blade for severing the fixed strapping.

Cutting devices for strapping are widely used to make strapped goods accessible. In the simplest case, such separating devices can be a pair of scissors that have a movable and a fixed blade. In addition, a clamp is usually provided to hold the severed strip. This is necessary to the extent that such severed strips often "pop open" at considerable speed and can thereby cause damage or, in the worst case, even injuries to operating personnel. Typical examples of such devices for severing a strip of strapping tape are disclosed in US Pat EP 1 495 978 B1 described.

In the generic prior art according to EP 3 013 538 B1 a battery-operated tape cutting device is used. This has a pressure device that can be moved into contact with the strapping. In this way, the band can be fixed against a foot. While the pressure device fixes the tape, an additional cutting blade cuts the tape on a pushing edge. This has basically proven itself.

In addition, according to the prior art US 8 160 748 B2 described the possibility of moving such a separating device with the aid of a three-dimensional robot arm. To the To position the separating device, a tape detection device is also provided. In the present case, it is a camera.

However, the known cutting devices for strapping are associated with the disadvantage that, in particular, steel straps with a large material thickness, such as those used for wrapping and holding together metal band coils, can practically not be cut or with such strapping it cannot be ensured that the respective severed end does not pop open in an uncontrolled manner despite provided clamping devices.

Because the known clamping devices ultimately ensure a hold of the steel strips concerned, for example with the help of friction surfaces, as they are in the further prior art according to WO 2008/052175 A1 are used by way of example. However, such friction surfaces fail in the field of application described because, for example, steel strips for strapping metal strip coils can have prestresses of 40 to 50 kN or even more. Such pretensioned belts can practically not be controlled with conventional clamping devices, so that the previously known separating devices fail in the field of application described. The invention aims to provide a remedy here overall.

The invention is based on the technical problem of providing such a severing device for strapping tapes that safely and reliably prevents the severed strapping tape from jumping open and securely holds the severed end of the strapping tape.

To solve this technical problem, a generic severing device for strapping is within the scope of the invention characterized in that the pressure element is designed as a punch which at least partially penetrates the strapping band.

In the context of the invention, the pressure element, in contrast to the prior art according to the EP 3 013 538 B1 not only that the strapping is fixed between the foot and the pressure element. Rather, the pressure element penetrates as a punch more or less into the strapping and thereby ensures a pronounced punching in the strapping. As a result of this punching and a punch produced by the punch in the strapping band, the severed end of the strapping band is practically not held in place by frictional forces. Rather, the punch penetrating completely or partially into the strapping ensures that the severed end of the strapping is held in place in the manner of a claw with the aid of the punch. In this way, the previously mentioned pre-tensioning in such strapping tapes in the strapped state can be controlled, which are values of 50 kN and even more. This is expressly not possible with the separation devices made available so far.

In fact, the cutting device according to the invention for strapping bands opens up the option of being able to cut thick and high-strength strapping bands (made of steel) for the first time. Such so-called high-performance belts have tensile strengths of 1,200 N and more, for example. In addition, breaking loads of more than 50,000 N or 50 kN and even up to 57 kN are observed for high-performance belts that are consequently equipped with a material thickness greater than that of conventional steel belts, for example 1.4 mm and more. As a result of the use of high-strength steel, special requirements are placed on separating devices that are not met by the separating devices known in the prior art , however, can be cut properly and safely for the first time using the solution according to the invention.

According to an advantageous embodiment, the design is also made such that the foot has a receptacle for the punch. As a result, when it penetrates the strapping band, the punch can overall form the previously mentioned punched item which, either alone or together with the punch, escapes into the receptacle in the foot when it is formed. At the same time, the receptacle together with the punch and also the die cut into the receptacle can provide an additional hold for the severed end of the strapping band. This reliably prevents the severed strapping band and, in particular, steel band from jumping open, and any damage or even health hazards for operating personnel can be reliably prevented.

The punch can have very different shapes and cross-sectional designs. As a rule, the punch has a polygonal cross section. Trapezoidal, square, hexagonal, octagonal or other polygonal shapes can be implemented and realized here. It is also conceivable to make the punch oval or round in cross section. In principle, combinations are also conceivable.

A design of the punch that has a triangular cross-section has proven particularly advantageous. Because this allows any expansion forces of the strapping to be cut to be absorbed particularly well. In fact, such expansion forces generally act along the axis of symmetry of the relevant triangle and are thereby over the respective legs of the Triangle introduced evenly into the punch, which in turn is not excessively stressed in this way.

The punch also has a nose protruding in the pressing direction and an adjoining stop shoulder. Because the nose of the punch protrudes, it ensures that the nose penetrates the strapping and can also penetrate it. As a rule, the nose is located at the tip of the strapping tape, which is triangular in cross-section, so that the tip can penetrate the strapping tape particularly easily and effectively and cut it, as it were, in the area of the tip. At the same time, the stop shoulder adjoining the protruding nose ensures that the die-cut that is formed in this way in the strapping band is bent with respect to a band surface.

That is, the die-cut is still connected to the strapping on its base side opposite the tip of the triangle. As a result, the base side of the triangular die cut can be bent with respect to the surface of the tape, with the help of the stop shoulder. The die-cut formed in this way is thus designed as a whole in a triangular manner following the shape of the punch and is connected to the strapping band with the base side of the triangle. At the same time, the die-cut is bent in relation to the surface of the tape and as a result dips more or less pronounced into the receptacle in the foot. In any case, the punch, the die cut and the receptacle in the foot together ensure that the severed end of the strapping is properly held and is only released by the severing device when the punch moves back into its original position.

The punch is generally arranged approximately centrally in comparison to the foot. The cutting blade is usually an upper knife which interacts with a foot edge as a lower knife. This means that one edge of the foot, the foot edge, functions as a lower knife, while the cutting blade takes on the function of the upper knife in the scissors or metal scissors realized in this way. In this way, cutting angles can be introduced into the strapping band to be severed, which are basically designed to be variable and, for example, are or can amount to values in the range from 1 ° to 50 ° based on the transverse direction of the band, for example.

The punch and the cutting blade are each for the most part moved vertically compared to the foot or are designed to be accordingly vertically movable compared to the foot. For this reason, a common punch can be provided to act on both the punch and the cutting knife. In this context, the design is usually made so that the punch is equipped with a protrusion with respect to the cutting knife and, taking this protrusion into account, is connected to the common punch together with the cutting knife. The protrusion ensures that the punch first penetrates completely or partially into the strapping band and in this way holds the end of the strapping band to be severed subsequently. Only when the punch has penetrated the strapping completely or partially does the cutting knife, as an upper knife, in conjunction with the bottom edge as a lower knife, ensure the desired cutting process and the severing of the strapping.

The punch and / or the cutting knife are generally mounted on a common flange. The flange also takes care of theirs Linear guide when applying the stamp. For this purpose, the punch and the cutting knife are oriented opposite one another in comparison to the flange in the middle. In addition, the punch or the cutting knife can be mounted floating relative to the flange. In principle, the flange as a whole can also have a floating mounting relative to a machine frame. As a result, when the punch penetrates the strapping and due to its tensile stress, overall reduced shear forces act on the punch. The same may apply to the cutting knife. As a rule, however, it is mainly the punch that is floating relative to the flange. For this purpose, one or more springs are generally provided which, on the one hand, provide a perfect linear guidance of the punch with the aid of the flange, but on the other hand allow a lateral movement of the punch.

In addition, a tape detection device is provided for detecting the position in relation to the strapping to be cut. That is to say, with the aid of the strap detection device, the previously described cutting device according to the invention is aligned with respect to the strapping to be cut. Such a position detection and tape detection device is particularly recommended for the case that the cutting device works in a stationary manner and is connected, for example, to a robot arm or generally to a three-dimensionally movable control device. For mobile use of the cutting device, which is also possible, such a tape detection device is of course not absolutely necessary because the positioning of the cutting device is carried out by an operator.

The tape detection device is usually designed as a laser measuring device. With the aid of the laser measuring device, for example, the surface of a metal strip coil strapped using a steel strip is scanned. The strapping appears on this surface as a rectangular elevation, which can be determined via the laser measuring device and at this point by respective distance measurements. This allows the position of the strapping to be determined and the cutting device to be precisely aligned. In addition, after the position of the strapping has been determined, the separating device is usually pushed down with the foot under the tensioned strapping with the help of the three-dimensional adjusting device so that the pushing edge implemented on the foot ensures that the strapping can be lifted from the strapped material and the foot can be pushed under. Only then does the separation process already described in detail take place.

For the drive of the punch and the cutting knife, all drive forms that are fundamentally possible in this context can be used. In fact, a hydraulic and / or pneumatic and / or electric drive is conceivable at this point. If an electric drive is used, it can work with AC voltage connected to the mains. However, it is also possible to use battery operation with a handheld device. Consequently, the separating device can be designed to be mobile or stationary as a whole.

As a result, a cutting device for strapping is made available, which works particularly safely and reliably. This also and in particular applies to strapping or steel straps which are under particularly high pretensioning during the cutting process, as is observed, for example, with steel straps used for strapping metal strip coils can be used. In the case of strapping bands of this type, the cutting device implemented according to the invention ensures that the severed end of the strapping band in question cannot jump open in an uncontrolled manner and cause damage or injury to operating personnel. This is not possible with previously known separating devices used in practice. This is where the main advantages can be seen.

Fig. 1

Eine Trenneinrichtung in einer Übersicht,

Figuren 2A bis 2D

Details der Trenneinrichtung nach Fig. 1 aus unterschiedlichen Blickwinkeln und

Fig. 3

das abgetrennte Ende des Umreifungsbandes mit dem ausgebildeten Stanzling.

In the following the invention is explained in more detail with reference to a drawing showing only one embodiment; show it:

Fig. 1

A separator in an overview,

Figures 2A to 2D

Details of the separation device according to Fig. 1 from different angles and

Fig. 3

the severed end of the strap with the formed die cut.

In the figures, a separating device is shown, with the help of which in the Fig. 1 indicated straps 1 can be severed. The straps 1 are mostly steel straps. The invention is of course not restricted to this. According to the exemplary embodiment, the steel bands or strapping bands 1 in question are looped around metal band coils (not shown in more detail) and are to be severed for further processing of the metal band coils. To do this, the Fig. 1 Separating device shown using a foot 2 with pushing edge 3 in the in Fig. 1 is pushed under the tensioned strap 1 by a double arrow shown direction. In addition, the in the Fig. 1 Separating device shown in the overview to a here in the Fig. 1 indicated and three-dimensional actuating device 5 be connected. The actuating device 5 is advantageously a robot arm. Of course, this only applies as an example. In addition, the actuating device 5 can in principle be dispensed with in the event that the separating device is designed to be mobile and is acted upon by an operator.

In any case, the one in the Fig. 1 The actuating device 5 shown ensures that the separating device, which is to be described in detail below, is pushed with its foot 2 under the tensioned strapping 1. The pusher edge 3 inclined in this connection ensures that this process can be carried out and that the tensioned strapping 1 is increasingly lifted from the strapped material. For this purpose, the pushing edge 3 may be in the against a horizontal Fig. 1 have indicated inclination corresponding to an associated angle of inclination α of approximately 10 °. Typically, angles of inclination α between 5 ° and 20 ° are observed. Of course, this is not restrictive. The angle of inclination α also specifies a cutting angle when the strapping tape 1 is severed, which is still to be described below.

In particular, the detailed representations in the Figures 2A to 2D now show the foot 2 with the pushing edge 3 and additionally a pressure element 4 and a cutting blade 5. With the aid of the pressure element 4, the strapping 1 can be fixed between the foot 2 and the pressure element 4. This fixation ensures during a cutting process with the aid of the cutting blade 5 that the tensioned strapping 1 does not spring open after severing and that the end of the strapping 1 severed by the cutting blade 5 is held. The cutting blade 5 for severing the fixed strapping 1 functions as an upper knife during this process. A foot edge 6 on the foot 2, on the other hand, takes on the function of a bottom knife 6. In this way, the movable cutting blade 5 and the foot edge 6 define a total of scissors 5, 6 or metal scissors 5, 6 if the strapping 1 is a steel band acts. Both the cutting blade 5 and the pressure element 4 are for the most part designed to be movable vertically in comparison to the foot 2, as shown by a double arrow in FIG Figure 2B indicates. According to the exemplary embodiment, a common and merely indicated punch 7 provides for the corresponding travel movement of the pressing element 4 and also of the cutting blade 5. The punch 7 can also be a cylinder. In any case, the stamp 7 performs the in the Figure 2B The illustrated traversing movements are vertical compared to the foot 2. A hydraulic drive may be used to drive the ram 7 or a cylinder at this point.

According to the invention, the pressing element 4 is designed as a punch which at least partially penetrates the strapping 1. According to the exemplary embodiment, the punch 4 is one which is triangular in cross section. Consequently, the foot 2 also has a corresponding receptacle 8 in the foot 2, which is also triangular in shape and is adapted to the shape of the triangular punch 4. As a result, the punch 4 as a whole can penetrate the strapping band 1 or at least partially penetrate it and dip into the receptacle 8 in the foot 2.

The punch 4 is on the foot side with a in the pressing direction or the direction of travel of the punch 4 according to the double arrow in FIG Figure 2B protruding nose 9 equipped. It also joins the protruding nose 9 to a stop shoulder 10 that is set back. The protruding nose 9 is provided in the area of a tip of the triangle of the triangular cross-sectional shape of the punch 4. In contrast, the stop shoulder 10 extends in the direction of a base side of the triangle in question opposite the tip.

In this way, the penetrating into the strapping 1 hole punch 4 forms a in the Fig. 3 indicated die cut 11 in the strapping 1. This die cut 11 in the strapping 1 is produced in that the punch 4 with its protruding nose 9 cuts through the strapping 1. Since the stop shoulder 10 adjoining the protruding nose 9 springs back with respect to the nose 9, the die cut 11 is connected to the strapping 1 unchanged with the base side of the triangle. In this way, the stop shoulder 10 adjoining the projecting nose 9 bends the die cut 11 with respect to a band surface of the strapping band 1.

During this process, the bent die cut 11 can more or less dip into the receptacle 8 in the foot 2. In this way, the punch 4, the bent punch 11 and the receptacle 8 in the foot 2, taken together, ensure that the subsequently severed end of the strapping 1 is securely held by the severing device. This is because the punch 4 penetrating into the strapping band 1 functions as it were like a claw dipping into the strapping band 1 and ensures a secure hold.

The punch 4 is arranged approximately centrally in comparison to the foot 2. The same applies to the receptacle 8 in the foot 2, which cooperates with the punch 4. In addition, the detailed representations in FIG Figures 2A to 2D that the punch 4 is connected to the common punch 7 with a protrusion Ü opposite the cutting knife 5. This protrusion Ü is dimensioned such that when the punch 7 is acted upon, the punch 4 first penetrates the strapping 1 and the bent die cut 11 as shown in FIG Fig. 3 forms. As a result, the end of the strapping 1 which is still to be severed subsequently is securely held. Only after this fixing of the end of the strapping 1 to be severed does the cutting blade 5 ensure that the strapping 1 is severed. For this purpose, the cutting blade 5 and the foot edge 6 define the cutting knife 5, 6 already described above. A flange 14 for the common mounting of the punch 4 and the cutting knife 5 ensures their proper linear guidance.

In order to detect the position and align the described separating device with respect to the strapping tape 1 holding the goods to be strapped, a tape detection device 12 can also be provided, which is shown in FIG Fig. 1 is only indicated. The tape detection device 12 works in the present case as a laser measuring device, as has already been described in the introduction. To control the three-dimensional actuating device S, a common control unit 13 is provided, which processes corresponding measured values from the tape detection device 12 and activates the actuating device S accordingly so that it can move the foot 2 to cut the strapping 1 and thus the cutting device as a whole.

A pneumatic motor or an electric drive can be used to drive the stamp 7. If an electric drive is used, it can be operated with mains voltage or alternating voltage, for example. Mobile use is also possible with a battery-operated electric drive possible and is covered by the invention. Consequently, the separating device can be designed to be mobile as a hand-held device or to be stationary in connection with the actuating device S described and operating in three dimensions. Both are expressly possible.

Based on a comparative consideration of the Figures 2A to 2D it can be seen that the punch 4 and the cutting knife 5 are mounted on the common flange 14. The flange 14 ensures the desired linear guidance of both the punch 4 and the cutting knife 5. In addition, a floating mounting can be implemented in this context. In fact, according to the embodiment, the procedure is such that the flange 14 allows a lateral movement of the punch 4 by means of springs attached on both sides and not shown in detail, that is, in the longitudinal direction of the strapping band 1 cushioned. As a result, any shear forces acting on the punch 4 are reduced.

Claims (15)

1. Separating device for straps (1), having a displaceable pressing element (4), further having a foot (2) with an undercut profile (3) for the strap (1) that can be fixed between the foot (2) and the pressing element (4), and having a cutting blade (5) for cutting through the fixed strap (1), characterized in that the pressing element (4) is designed as a hole punch (4) at least partially penetrating the strap (1).
2. Device according to Claim 1, characterized in that the foot (2) has a holder (8) for the hole punch (4).
3. Device according to Claim 1 or 2, characterized in that the hole punch (4) is designed polygonal, in particular triangular, oval or round in cross-section.
4. Device according to one of Claims 1 to 3, characterized in that the hole stamp (4) is designed with a nose (9) protruding in the pressing direction and an adjacent stop shoulder (10).
5. Device according to Claim 4, characterized in that the protruding nose (9) penetrates the strap (1) and the adjacent shoulder (10) bends a stamped piece (11) formed hereby against a strap surface.
6. Device according to one of Claims 1 to 5, characterized in that the hole punch (4) is arranged in approximately the centre of the foot (2).
7. Device according to one of Claims 1 to 6, characterized in that the cutting blade (5) as the upper blade interacts with a foot edge (6) on the foot (2) as the lower blade.
8. Device according to one of Claims 1 to 7, characterized in that the hole punch (4) and the cutting blade (5) are respectively designed to be largely vertically moveable compared to the foot (2).
9. Device according to Claim 8, characterized in that a shared stamp (7) is provided for applying pressure to the hole punch (4) and the cutting blade (5).
10. Device according to Claim 9, characterized in that the hole punch (4) is connected to the shared stamp (7) opposite the cutting blade (5) with a projection (Ü).
11. Device according to one of Claims 1 to 10, characterized in that the hole punch (4) and/or the cutting blade (5) are mounted on a shared flange (14), preferably floating.
12. Device according to one of Claims 1 to 11, characterized in that a strap detection device (12) is provided for detecting the position relative to the strap (1) to be cut through.
13. Device according to Claim 12, characterized in that the strap detection device (12) is designed as a laser measuring device.
14. Device according to one of Claims 9 or 10, characterized in that a hydraulic and/or pneumatic and/or mains or battery-operated drive is provided for the stamp (7).
15. Device according to one of Claims 1 to 14, characterized in that it is designed to be mobile or stationary.

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