GB2327060A - Method of shearing and guiding metal strip and apparatus therefore - Google Patents

Abstract

The invention relates to an apparatus for the combined shearing and deflecting of metal strip comprising two cutting edges provided on corresponding blades 13, 14 between which the metal strip passes, and two coiling spools 15, 16 such that immediately after the strip has been cut at least one of the blades forms a deflecting surface to deflect the strip into the path of one of said cooling spools. Pinch rolls 11 are provided before the blade means to guide the path of the strip onto the coiling spools. Preferably one of the blades is movable between a first position permitting the strip to pass between the first and second cutting edges and a second position alongside the second blade. During the course of movement of the first blade from the first position to the second position, the first blade shears through the strip.

Description

Method of Shearing and Guiding Metal Strip and Apparatus Therefor.

The invention relates to a method of shearing and guiding metal strip and apparatus there for. In particular to guide the strip onto a coil at the end of a rolling mill line and to shear and transfer the strip to a second coil when a first coil is complete, whilst at the same time permitting the continuous production of the strip at an uninterrupted rate.

Such shear and guiding systems for shearing and guiding the strip to alternate coils are well known in the art. In fact more than two coils may be used if the cycle time for the removal of the completed coil is greater than the time to complete the coiling of a single coil.

An example of such known systems generally have the construction as shown in the schematic configuration in fig. 1. The strip 2 is travelling from left to right in the direction of arrow A. The first stage of the shearing and guiding system is a rotating shear 1 which comprises two cutting edges each mounted on a rotatable support on opposite sides of the strip so that the blades are coincident with the strip and act together to cut the strip when the rotatable supports are rotated. The rotatable supports rotate in the direction of the strip, the upper support in an anti-clockwise direction and the lower one in a clockwise direction. There are also two coiling spoils 5, 6 onto which the strip is alternately wound and deflecting rolls 3, 4 corresponding respectively to the two coiling spools. Thus, when the strip is being coiled onto the spool 6, the deflecting rolls 4 are engaged to guide the strip onto the spool 6, as shown in fig. 1. When the spool 6 is full and the coil is complete, the rotating shear 1 is enacted and the strip is cut (clearly the coil will not quite be complete at the time of cutting but will be just less than complete by the amount of the distance of the strip from the rotating shear to the coil).

Immediately after the strip is cut the deflecting rolls 3 are engaged to guide the strip to the second spool 5 which is then filled to form the next coil whilst the previous coil is removed from the spool 6.

This known system is typical of the way that strip is formed into coils at the end of the strip production. There are variations on this theme in which the spools are movable to pick up the strip after each cut, and also there are alternative means of guiding the strip, some of which rely merely on gravity or the inertial movement of the strip to cause the strip to fall in line with the spool.

There are a number of disadvantages with these known systems that are overcome with the present invention. The first is that it is necessary to engage the guiding rolls immediately after the cutting has taken place and this can cause problems for high strip speeds. If the guiding rolls are engaged too soon then the previous strip length will be engaged and this will cause it to be deflected in the wrong direction. Alternatively if the engaging roll is engaged too late the next strip length will proceed on its previous path and may overshoot the corresponding spool. Thus the engaging roll must move very quickly into and out of position and the dynamic limitations of this movement of the engaging rolls limits the strip speeds that can be used.

Thus it is necessary to ensure that the activation of the engaging rolls is precisely timed with the action of the rotating shears. Thus it is necessary for these separate shearing and engaging means to be co-ordinated to work together. Whether automatic or manual means are used to co-ordinate the action of the shear and engaging rolls there is a certain tolerance in the desired time delay and actioning of the engaging means and thus when the strips speeds are increased this tolerance of the time is required to be much lower than is possible and the coiling process fails.

Simiiiily for systems which rely on inertia or gravity, the strip speeds are limited because the strip does not fall in time or in a predictable way because it is influenced by aerodynamic effects.

It is therefore an objective of the invention to overcome these problems with known systems and specifically to provide an apparatus for shearing and deflecting metal strip which can work at high strip speeds and with lower strip thickness.

According to the invention there is provided an apparatus for the combined shearing and deflecting of metal strip comprising first and second cutting edges provided on first and second blades, between which the metal strip passes, and first and second coiling spools, characterised in that immediately after the strip has been cut at least one of the first and second blades forms a deflecting surface to deflect the strip into the path of one of said first or second cooling spools.

Preferably pinch rolls are provided before the first and second blade means to guide the path of the strip onto the first or second coiling spools.

Preferably, the first blade is movable between a first position permitting the strip to pass between the first and second cutting edges and a second position alongside the second blade. During the course of movement of the first blade from the first position to the second position, the first blade shears through the strip.

Preferably the first blade is pivotally mounted and actuated to move between the first and second position by a hydraulic cylinder.

Preferably the deflecting surface is approximately tangential to the path of the strip in the region closest to the cutting edges.

Preferably the first and second coiling spools may be arranged on a carousel so that when the first spool is full and the strip is directed to the second spool the first coil is removed and the carousel rotated by half a turn so that the second spool is moved to the removal position whilst it is being coiled and the first spool is moved to the coiling start position ready for the next strip end to be directed onto it.

Additional rollers or moving belts may be used to direct the strip path onto the spools.

According to the invention there is provided a method for the combined shearing and deflecting of metal strip, wherein the metal strip is passed between first and second cutting edges provided on first and second blades, to a first coiling spool and wherein when said first coiling spool has the desired length of strip the strip is cut by movement of one of the first and second cutting edges, characterised in that immediately after the strip is cut it is deflected by at least one of the first and second blades forming a deflecting surface into the path of a second cooling spool.

The invention will now be described in more detail by reference to an exemplary embodiment with reference to the attached figures in which: fig. 1 is a schematic view of a shearing and deflecting system of the prior art, and fig. 2 is a schematic view of a combined shearing and deflecting unit according to an embodiment of the invention.

The prior art system shown in fig. 1 has been described in the background to the invention above.

Referring now to the embodiment of the invention shown in fig. 2 the metal strip 12 is initially being coiled onto the coiling spool 16. The pinch rolls 11 ensure that the path ofthe strip onto the coiling spool 16 is precisely defined The combined shearing and deflection operation is carried out by means of an upper combined blade and deflector 13 and a lower combined blade and deflector 14. In this embodiment the upper combined blade and deflector unit 13 is movable and is actuated by an hydraulic cylinder 7.

The upper and lower combined blade and deflector units 13, 14 each comprise corresponding leading edges or cutting edges 17, 18 which cause the strip to shear when the blades are engaged.

When it is desired to start coiling on coiling spool 15 instead of coiling spoo 16, the upper combined bladed and deflector unit is pivoted downwards by the hydraulic cylinder 7. As it meets the lower blade and deflector unit 14 the corresponding leading edges 17, 18 cross, and the strip is cut. The continuing downward motion of the upper combined blade and deflector unit causes the corresponding deflecting surfaces of the upper and lower combined blade and deflector units to form a deflection path for the strip which diverts the strip on to the coiling spool 15.

It will be appreciated that an important aspect of this combined cutting and deflecting operation is that the deflector part of the combined blade and deflector units 13, 14 should ideally be as close as possible to the tangent of the original strip path in order to minimise the impact of the strip whereas the cutting action itself ideally requires a motion which is perpendicular to the strip path. Each combined blade and deflector unit 13, 14 comprises a deflecting blade body which comprises a concave curved surface to deflect the strip in the desired direction.

In this embodiment the first and second coiling spools 15, 16 are arranged on a carousel (not shown) so that when the first spool 16 is full and the strip 12 is directed to the second spool the first coil is removed. The carousel is then rotated by exactly half a complete turn so that the second spool 15 is moved to the removal position whilst it is being coiled and the first spool 16 is moved to the coiling start position ready for the next strip end to be directed onto it. Before the carousel is rotated the first and second combined blade and deflector units are moved out of the path of the strip during the rotation and moved back in to the operating position when the rotation of the carousel is complete.

The apparatus is then ready to repeat the cutting and deflection process again.

Additional rollers or moving belts (not shown) may be used to direct the strip path onto the spools.

It will be appreciated that the invention is not limited to the embodiment described above but is intended to include other embodiments within the scope of the invention as defined in the appended claims.

Claims (10)

1. An apparatus for the combined shearing and deflecting of metal strip comprising first and second cutting edges provided on first and second blade means between which the metal strip passes and first and second coiling spools, characterised in that immediately after the strip has been cut at least one of the first and second blade means forms a deflecting surface to deflect the strip into the path of one of said first or second coiling spools.

2. An apparatus according to claim 1, characterised in that pinch rolls are provided before the first and a second blade means to guide the path of the strip onto the first or second coiling spools.

3. An apparatus according to claim 1, characterised in that the first blade means is movable between a first position permitting the strip to pass between the first and second cutting edges and a second position alongside the second blade, and during the course of movement of the first blade from the first position to the second position, the first blade shears through the strip.

4. An apparatus according to claim 3, characterised in that the first blade is pivotally mounted and actuated to move between the first and second position by a hydraulic cylinder.

5. An apparatus according to claim 3, characterised in that the second blade is also movable during the cutting action.

6. An apparatus according to claim 1, characterised in that the deflecting surface is approximately tangential to the path of the strip in the region closest to the cutting edges.

7. An apparatus according to claim 6. characterised in that the deflecting surface is concavely curved.

8. An apparatus according to claim 1, characterised in that the first and second coiling spools are arranged on a carousel so that when the first spool is full and the strip is directed to the second spool the first coil is removed and the carousel rotated so that the second spool is moved to the removal position whilst it is being coiled and the first spoo: is moved to the coiling position ready for the next strip end to be directed onto it.

9. An apparatus according to claim 1, characterised in that rollers or moving belts are provided in addition to the deflecting surface to direct the strip path onto the spools.

10. A method for the combined shearing and deflecting of metal strip, wherein the metal strip is passed between first anci second cutting edges provided on first and second blades to a first coiling spool and wherein when said first coiling spool has the desired length of strip the strip is cut by movement of one of the first and second edges, characterised in that immediately after the strip is cut it is deflected by at least one of the first and second blades forms a deflecting surface into the path of a second cooling spool.