WO2000048932A2

WO2000048932A2 - Method for cutting sheet-metal plates into sheet-metal strips and a cutting device for carrying out the same

Info

Publication number: WO2000048932A2
Application number: PCT/CH2000/000035
Authority: WO
Inventors: Peter Taiana; William Ferretti
Original assignee: Elpatronic Ag
Priority date: 1999-02-19
Filing date: 2000-01-26
Publication date: 2000-08-24
Also published as: EP1152968A2; KR20010102048A; WO2000048932A3; CN1341046A; AU3029500A; JP2002537131A; TW553879B; CH694504A5

Abstract

The invention relates to a cutting device (1) for cutting stacked sheet-metal plates into sheet-metal strips using a cutting unit (12). Holding and positioning means (25 to 29 and 13 to 16) are arranged above said stack. This makes a space-saving arrangement possible while maintaining a high degree of cutting precision. The cut sheet-metal strips are fed to another cutting unit by collectively feeding all strips up to a separating point. This simplifies the feeding device and the adaptation thereof to different sheet-metal thickness.

Description

Process for cutting metal sheets into sheet metal strips and cutting device for carrying them out

Technical field

The invention relates to a method for cutting sheet metal sheets into sheet metal strips according to the preamble of claim 1. Furthermore, the invention relates to a device for cutting sheet metal sheets according to the preamble of claim 5. Furthermore, the invention relates to a method for conveying sheet metal strips according to the preamble of claim 10 and a device for conveying sheet metal strips according to the preamble of claim 13.

State of the art

It is known to cut metal sheets into strips by means of a cutting device, in particular by means of a circular knife shear. If two cutting devices are arranged to form a pair of angle scissors, the first strips cut from the sheet can be fed directly to a second pair of scissors, each of which cuts several sheet metal sections from the first strips, for example likewise with a circular knife scissors. If a precise cutting position and high cutting precision of the cuts are required, especially when cutting printed or unprinted metal sheets, which are processed into can frames, it is customary according to the prior art to first stack the respective metal sheet stacked from a sheet metal stack into a next to the stack arranged positioning bed to transport, in which a calming phase and a precise alignment of the sheet for the first step takes place. From this positioning bed the feed takes place into the circular knife scissors, in which the table is cut into strips in a known manner. The provision of the sheet calming and positioning bed is complex and increases the space requirement of the unit destacker / circular knife shear considerably.

Presentation of the invention

The invention is therefore based on the object of providing a method for cutting metal sheets into strips which does not have this disadvantage. This is achieved in a method of the type mentioned at the outset with the characterizing features of claim 1.

Because the positioning step is carried out above the stack, there is no need for a separate positioning bed between the stack and the cutting device, or the cutting device can be arranged directly next to the stack, which significantly reduces the space required for the stacking and cutting device.

The invention is also based on the object of providing a device for cutting metal sheets into strips, which has a compact structure with high cutting position accuracy.

This object is achieved in a device of the type mentioned by the characterizing features of claim 5.

Due to the fact that a holding device to which the sheet metal positioning means are assigned is arranged above the sheet stack or above the receptacle provided for this purpose, the cutting device can be positioned directly next to the sheet stack receptacle, which is a very compact, space-saving construction without loss of cutting position accuracy compared to the conventional one Solution results.

According to the prior art, the several sheet metal strips emerging from the cutting device in parallel next to one another arrive in a conveying device in which they are separated and individually separated by conveying cams. are required, for example to the already mentioned second cutting device, which cuts several sections from each strip. The corresponding conveying device is complex and must be set up anew each time the strip width or the cutting line distance of the first cutting device is changed, since the distance between the plurality of successive conveying cams of the conveying device must be matched to the strip width in accordance with the prior art. The corresponding set-up work when changing the cutting line distance is time-consuming and therefore leads to longer machine downtimes or considerable costs.

The invention is therefore also based on the object of providing a method for conveying the sheet metal strips delivered at the outlet of a cutting device which does not have these disadvantages. This object is achieved by a method of the type mentioned at the outset with the characterizing features of claim 10. The fact that the strips are initially conveyed together to a separation point means that there is no need for funds in this area that are adapted to the strip width, since the joint conveyance can take place independently of the strip width. In a preferred embodiment, the joint conveyance takes place by means of a conveying means which contacts all strips and which is selective for all strips or only for the strip which is foremost in the conveying direction. In a further embodiment, a common conveying means is provided which contacts only the rearmost strip, in which case means are preferably provided which prevent the strips from being pushed over one another. The invention is further based on the object of providing a device for conveying the sheet metal strips delivered at the outlet of a cutting device create, which does not have the disadvantages mentioned. This object is achieved in a device of the type mentioned at the outset with the characterizing features of claim 13.

BRIEF DESCRIPTION OF THE DRAWINGS The exemplary embodiments of the invention are explained in more detail below with reference to the drawings. It shows

Figure 1 is a side view of a cutting device for cutting metal sheets into strips;

Figure 2 is a plan view of the device of Figure 1; Figure 3 schematically from above to a first

Point in time a conveyor device for receiving cut strips and transporting them to a further cutting unit;

FIG. 4 schematically shows a vertical section of the conveyor device from FIG. 3;

Figure 5 shows the conveyor device of Figure 3 schematically from above at a further time;

6 shows a schematic vertical section of the conveyor device according to FIG. 5; Figure 7 schematically shows the conveyor of

Figure 3 or Figure 5 from above at a further time;

Figure 8 is a schematic vertical section of the conveyor of Figure 7; FIG. 9 shows a further top view of the conveyor device at an even later time;

Figure 10 is a vertical sectional view of the conveyor of Figure 9, and

Figure 11 is a side view of another conveyor. BEST WAY OF IMPLEMENTING THE INVENTION FIG. 1 shows a side view of a cutting device 1, parts of the machine frame 2 being omitted in order to give a better view of the device. The device has a receptacle 3 on which a sheet metal stack 5, which is arranged on a pallet 4, is received in the device 1. The stack can be held in the stacking area by lateral guides and spreading magnets 6. Above the stack there are a large number of stacking elements 7, each of which can detach and lift the top sheet of the stack from it, for example by means of the pneumatically operated suction cups indicated. The stacking is not explained further here, since it is known as such. In FIG. 1, the cutting unit 12 can also be seen, which in the present case consists of a circular knife shear with several pairs of round knives 8 and 9. Such circular knife scissors are also known and do not need to be explained further here. The plan view of the cutting device 1 in FIG. 2 shows how the cutting unit 12 extends over the entire width of the device, several pairs of circular knives being provided for cutting the respective sheet metal sheet in order to form the strips. In Figure 2, in which the same reference numerals designate the same parts so far, a holding device is now shown in the view from above, which can hold a sheet stacked from the stack above the stack, regardless of the stacking members. Two rails 25, 26, 27 and 28 are shown in FIG. 2, which extend in the longitudinal direction over the stack receiving position of the cutting device 1. The rails can be arranged on cross members 19 and 20 which extend across the device 1 on both sides of the stack receptacles. The stacking units 7 can also be arranged on the cross beams on longitudinal beams 30, 31 and 32. The beams can be placed on the cross beams like to be adjustable in the transverse direction by means of detachable guides in order to allow the stacking units 7 to be adapted to the sheet size. In the arrangement of the rails 25 and 28 shown, likewise on these guides, these rails are also adjusted to the respective sheet metal size, together with the stacking elements. In the example shown, a plurality of magnetic rollers 29 are arranged on the rails 25, which protrude slightly above the rail. If the top sheet is stacked upwards by the stacking units 7 from the stack 5, this results in the sheet resting against the magnetic rollers 29 and thus holding the sheet in the position above the stack, regardless of the stacking elements, which continue to move can drive up and let go of the sheet so that it is only held by the magnetic rollers 29. This is indicated schematically in FIG. 1 with only three magnetic rollers 29, the stacking elements not yet having reached their upper end position in which they no longer touch the sheet 22. Since the sheet 22 is held on rollers 29, it can be inserted between the circular knives by the insertion device 10 with its insertion edge 11, which can move in the direction of arrow A and back. According to the invention, however, the positioning and calming step for the plate 22, which is necessary for the necessary cutting position accuracy, is carried out in the holding position of the plate 22 on the rollers 29. This eliminates the positioning bed provided according to the prior art between the stack and the circular knives 8, 9, which has at least the dimensions of a metal sheet, and in which, according to the prior art, the sheet is inserted directly after stacking without the provision of a separate holding device 25 to 29 and then calm down and position yourself. In the present case, the positioning elements are therefore also arranged above the stack and not in a separate positioning bed which does not exist according to the invention.

With a view of FIG. 2, the positioning elements are shown with the side stop rollers 13 and 14 to be located laterally on the metal sheet, and the side stop rollers 15 and 16. The sheet currently held stationary by the magnetic rollers 29 of the holding device above the stack is e.g. by a transverse movement of the rollers 13 and 14 against the rollers 15 and 16, so that there is a precisely defined position of the sheet 22. The magnetic rollers 29 allow a corresponding displacement of the sheet and the force exerted by the rollers 13 and 14 on the edge of the respective sheet has no influence on the edge quality of the sheet strips. After the positioning and calming phase, the respective sheet metal held by the rollers 29 is pushed through the insertion member 10, 11 between the pairs of circular knives 8, 9 and is grasped by these and cut into strips, as is known per se. Thereafter, the next sheet 23 can be stacked from the stack 5 and held by means of the stacking units 7 on the magnetic rollers 29 for planting and by these, after which the calming and positioning step takes place again and also the sheet 23 positioned and calmed in relation to the stacking vibrations between the Circular knife pairs is inserted.

The holding device can of course also be designed differently than with the magnet devices shown. For example, a plate provided with a sliding coating and a plurality of holes can be used, which holes are connected to a pneumatic vacuum source, so that the stacked sheet metal is held on the plate by negative pressure. The sliding coating, such as a Teflon coating or a chrome plating of the plate, still allows the respective sheet to be positioned through the side beat 13 to 16 and the insertion between the circular knife scissors through the insert member 10, 11th

Carrying out the positioning and calming step above the stack of sheets results in a much more compact cutting device than according to the prior art, which has provided a large positioning and calming bed next to the stack holder and thus has arranged the cutting device at a large distance from the stack holder. In the cutting device according to the invention, the cutting unit 12 can be arranged directly next to the stack receptacle, which significantly reduces the footprint required for the cutting device 1.

A further aspect of the invention will now be explained with reference to FIGS. 3 to 11, FIG. 3 schematically showing a plan view of a cutting device which, in addition to the cutting unit 12 already described, has a further cutting unit 52 arranged at right angles thereto, which likewise has a round knife scissors with a plurality of pairs of circular knives 8 and 9 can be. In FIG. 3 it can be seen how sheet metal strips 40 to 43 are formed from sheet metal plate 22, which is just located in cutting unit 12, which are delivered in the direction of the arrow to a schematically illustrated conveyor device, which will subsequently transport the sheet metal strips to cutting unit 52. The stacking and calming and positioning of the metal sheets can preferably take place in the way that has been explained in the present case with reference to FIGS. 1 and 2. The metal sheet 22 could, however, also come from a conventional cutting device with a separate positioning and calming bed in front of the cutting unit 12. In principle, this has no influence on the functioning of the conveyor device for conveying the sheet metal strips 40 to 43 to the cutting unit 52. This conveyor device can therefore also be used in a conventional cutting device. It can be seen in FIG. 3 and in FIG. 4 that the conveyor device has a plurality of longitudinal beams 45 to 50 which can be connected to one another, for example by inserts 71 (FIG. 4), to form a table. Conveyor belts run around the bars 45 to 50, which can be formed, for example, by toothed belts, which run in the direction of the arrows B shown in FIG. 3 and, for example, have a common drive 60, which acts, for example, on toothed belt rollers 60 'in order to drive belt all the way towards the cutting unit 52. Below the belt 56, magnets N / S can be provided in the bar, which attract the sheet metal to the respective belt. In the bars 45 to 50 there are also torsion bars 65 to 70 which extend over part of the length of the respective bar and are located in the output region of the cutting unit 12 and which end at a distance in front of the cutting unit 52 which is at least the width of one Sheet metal strip corresponds. The cross-sectional shape of the rods 65 to 70 corresponds to a circle with a cut

Circle segment, as can be seen in Figure 4 for the rods 66 to 68.

When the metal strips 40 to 43 are output from the cutting unit 12, the torsion bars 65-70, which preferably have a common positioning drive 79, which acts on the bars by means of a toothed belt on toothed belt rollers 72, are positioned as shown in FIG. 4, so that the full circular diameter of the torsion bars results in a support for the metal sheets which lies above the belt surfaces, so that the belts 54 to 59 cannot touch the metal strips 40 to 43. The metal strips are therefore advanced on the rods up to a stop 73, which is indicated in FIG. 5. When the metal strips have reached the stop 73, they have also left the cutting unit 12 completely and lie on the torsion bars of the conveying device. This position tion of the sheets is shown in Figure 6 in cross-sectional view. The torsion bars 65 to 70 can rotate when the sheet metal strips are pushed onto the conveying device in the push-on direction, as can be seen in FIG. 6, in which the respective torsion bar has rotated further than in FIG. 4, but with its diameter the sheet metal strips are still in contact prevents the transport belt. As the torsion bars 65 to 70 continue to rotate, the torsion bar 70 remaining inoperative in the sheet metal strip length and stop position of the stops 73 shown in FIG. 5, the sheet metal strips are lowered onto the transport belts 54 to 58, as can be seen in FIG. 8. This results in the entire sheet metal strips 40 to 43 being taken along by the transport belts and thus an overall transport of the sheet metal strips in the direction of the cutting unit 52, as can be seen in FIG. 7. When the foremost sheet metal strip 40 in the direction of transport has passed the area of action of the torsion bars, the total conveyance is canceled by the

Torsion bars again assume a position shown in Figure 10, in which there is a lifting of the sheet metal strips from the toothed belt. However, since the sheet metal strip 40 is no longer in the area of influence of the torsion bars, this results in further conveyance in the direction of the cutting unit 52, while the other sheet metal strips 41 to 43 are currently no longer being conveyed. The sheet metal strip 40 can now be brought in the correct cutting position in front of the cutting unit 52 by lateral positioning rollers 74 and 75 (FIG. 9), which are only indicated in the drawing, and can be brought in exactly parallel and positioned with one by conveyor cams 78 emerging from under the table plane insertion speed increased compared to the conveying speed can be inserted into the cutting unit 52. The corresponding provision of conveyor cams 78 arranged on conveyor chains, for example, is not explained in more detail here, since is known. It can be seen from the above description that with the present conveying device no new arrangement of the belt transport is necessary if the width of the sheet metal strips 40 or the cutting position of the first cutting unit 12 is changed. At most, it may be necessary to readjust the cams 78 in the event of a considerable change in width, but not the joint transport through the toothed belts. In this way, there is significantly less downtime when changing the cutting or strip width.

Figure 11 shows a schematic side view of a modified embodiment of the conveyor. The metal strips from the cutting unit 12 are also released into these. The sheet metal strips are conveyed together by conveying cams acting on the rear edge of the rearmost metal strip, in FIG. 3 this would be the sheet metal strip 43 with its rear edge 43 ′, which are indicated in FIG. 11 as two cams 81. The drive of these cams via conveyor chains is, since it is known in principle, not further explained here. The joint promotion of the metal strips in this way would, however, often lead to the metal strips being pushed one over the other if this is not prevented by suitable measures. FIG. 11 shows rods 83 and 84 which extend above and below the plane of the sheet metal strip in the conveying direction and are arranged in such a way that the sheet metal strips each bend slightly in a curve when they are inserted between rods 83 and 84, as indicated in the figure . This causes the sheet metal strips to lie securely against one another, or to prevent them from being pushed over one another, if these are jointly conveyed forwards towards the cutting unit 52 by the cams acting on the rearmost sheet metal strip on the rear edge. The metal strips 40 to 43 are not isolated, but are fed to the cutting unit 52 by means of the cams 81. This eliminates the usual support dernocken 78. The insertion speed of the cams 81 is above the cutting speed and the conveying speed of the cams 81 is below the cutting speed of the cutting unit 52 in order to avoid a collision between the sheet metal strip located in the cutting unit 52 and the inserting sheet metal strip. The strips 40 to 43 are only spaced apart when the cam speed is slower than the cutting speed of the cutting unit 52. In this cutting unit 52, as in the previous example, the sheet metal strips are cut into individual sheet metal sections. These sheet metal sections are conveyed away and, according to a preferred field of application of the described cutting device or the described conveying device, rounded and welded to form can bodies. An easily adjustable rotary cutting unit, as is shown, for example, in WO 94/00261, is preferably used as the cutting device.

Claims

claims

1. Procedure for cutting metal sheets (22, 23) into metal strips (40 to 43), in each of which individual sheets arranged to form a metal stack (5) are stacked from the stack and subsequently positioned and in the positioned position of a cutting device (12 ), in particular circular scissors (12, 8, 9), characterized in that the positioning step is carried out above the stack (5).

2. The method according to claim 1, characterized in that the metal sheets are delivered by a stacking device (7) to a magnetic holding device (25 to 29) arranged above the stack (5), on which the boards are positioned.

3. The method according to claim 1, characterized in that the metal sheets are delivered by a stacking device to a pneumatic holding device arranged above the stack (5), on which the sheets are positioned.

4. The method according to any one of claims 1 to

3, characterized in that a calming phase for the metal sheet is waited for before and / or after the positioning step.

5. Device for cutting metal sheets

(22, 23) for sheet metal strips (40 to 43) comprising a stacking device (7) arranged above a sheet stack holder (3) and a cutting device (12), in particular a circular knife shear (12, 8, 9), characterized in that that a holding device (25 to 29) and a positioning device (13 to 16) for the metal sheets are arranged in the area of the stacking device.

6. Device according to claim 5, characterized in that the cutting device (12) is positioned directly after the stacking device.

7. Device according to one of claims 5 or 6, characterized in that the holding device is formed by a plurality of magnetic rollers (29).

8. The device according to claim 7, characterized in that at least some of the rollers are arranged on rails (25 to 28) which can be positioned transversely to the cutting direction.

9. Device according to one of claims 5 or 6, characterized in that the holding device is formed by at least one plate with holes which are connected to a vacuum source in order to hold the respective metal sheet by means of vacuum, and that the plate on the the sheet metal stack holder facing side is provided with a surface texture that allows sliding of the held board on the plate.

10. A method for conveying sheet metal strips (40 to 43), which are delivered at the exit of a cutting device (12), to a further cutting device (52), in particular according to claims 1 to 4, characterized in that the strips (40 to 43 ) are first conveyed together to a separation point at which the front strip (40) in the conveying direction is spaced apart from the other strips (41 to 43), positioned and fed separately to the cutting device.

11. The method according to claim 10, characterized in that the other strips (41 to 43) are briefly stopped at the separation point, while the respective front strip (40) is conveyed on.

12. The method according to claim 10, characterized in that the foremost strip is accelerated relative to the other strips.

13. Device for conveying sheet metal strips (40 to 43) to a cutting device (52), in particular in a device according to claims 5 to 9, characterized in that all sheet metal strips At the same time, common funding (54 to 59; 81, 82) is provided.

14. The apparatus according to claim 13, characterized in that the conveying means has conveying elements (54 to 59) which contact all sheet metal strips at the same time.

15. The apparatus according to claim 13, characterized in that the conveying means comprises conveying elements (81, 82) which are arranged for contacting the rearmost sheet metal strip (43) of a row of sheet metal strips (40 to 43), and that means (83, 84 ) are provided which are designed to prevent sheet metal parts from being pushed over one another.

16. Device according to one of claims 13 or 14, characterized in that controllable selection means are provided in the region of the conveying elements, by means of which the contact between the conveying means and the metal strips can be interrupted and restored.

17. The apparatus according to claim 16, characterized in that the selection elements associated torsion bars (65 to 70) are provided, which cause lifting or resting of the sheet metal strips on the conveyor elements depending on the rotational position.