|Title of Invention||
|Abstract||A cantilevered cutter with at least one drum, which is equipped with a knife and the circumferential speed of which can be synchronized with the speed of advance of the rolled strip and with an anvil disposed opposite the drum, characterized in that the mass of the rolled strip, forcibly accelerated back by the knife drum, and the tension force of the rolled strip deflected away serve as anvil.|
Translation of Amended Pages of WO 00/62&64 (PCT/EPOO/03168)
The invention relates to a flying shear comprising at least one
drum provided with a blade, whose peripheral speed can be
synchronized with the feed rate of the rolling strip, and
comprising an anvil positioned opposite the drum.
Such symchronized shears are known, for example, from DE 196 3 7 862 A1 as high-speed shears for cutting rolling strip to length. In this connection, two oppositely positioned drums which can be advanced toward one another are used which are both provided with blades, or only one of the drums is provided with an anvil or is used as an anvil.
The advancing strokes are dimensioned such that the two blades of two oppositely positioned drums overlap at a minimal distance or the shearing edge of one blade rests under pressure against the anvil of the oppositely positioned drum or its periphery. However, it was found that for such shearing processes the wear of the blades and of the anvil surfaces, if employed, is undesirably high, and it was found that the manufacture of the shears must be realized within the most narrow tolerances - a factor increasing manufacturing costs - for achieving an exact placing of the blades, onto a anvil or for a defined cut with two blades in order to ensure perfect cutting efficiency.
GB 2 203 S77 A discloses already a shearing device comprising a blade and an anvil which are adjusted relative to one another such that the strip to be cut is only scored. By a later application of tensile force onto the strip, tearing occurs at the scored areas resulting in a separation of the scrip. In these shearing devices, an anvil drum, which must be synchronised in a complex way. is required in addition to the blade drum- Moreover, contacting of the strip with the anvil drum can cause damage to the strip.
The invention has the object to provide a shear according to the aforementioned kind whose wear and manufacturing costs are minimised and which allows broader manufacturing tolerances without impairing the cutting efficiency.
The object is solved by the features of claim 1. These make it possible, by only a partial penetration of a blade or a wedge into the rolling strip, to significantly reduce its cross-section at the cutting location in a defined way and to perform the
separation then by tensile forces exarted onto the rolling strip, wherein the use of an anvil drum with a correspondingly complex synchronization is eliminated. Advantageous and expedient features as well as features providing a further development of the invention can be taken from the dependent claims.
The features of the invention are explained in detail with the aid of the descriptions of one embodiment in connection with drawing illustrating it.
In the Figure, a blade drum 11 supporting a blade or wedge 10 is illustrated. The blade drum 11 is arranged at the end of a lever arm 12 having correlated therewith an eccentric 14 which is force-actuated and serves as an advancing device by means of a guide 13.
Usually, in the case of high-speed shears the blade drum 11 is positioned above the rolling strip 4 to such an extent that its blades 10 do not contact the rolling strip 4, For performing the cut, however, the blade drum 11, driven for several rotations at a peripheral speed matching the feed rate of the rolling strip, is advanced spontaneously by means of the advancing device in the direction toward the rolling strip so that the blade 10 penetrates the rolling strip 4 and cuts it leaving a residual thickness.
For a scrip which is moved slower, there is the possibility of eliminating the advancing device and, for each movement into the active position, of accelerating the blade drum 11, arranged at a fixed spacing to the rolling strip 4. for approximately one rotation of the blade drum 11 to a peripheral speed matching the speed of the rolling strip.
Such a tensile force is now exerted onto the rolling strip 4 advancing in the direction of the arrow that the rolling strip will tear at the separation location which is greatly weakened by the blade 10.
Accordingly, the separation is not performed purely as a cut. but instead only by a penetration of the blade 10 or of a wedge into the material of the rolling strip 4 to a degree that the strip is significantly weakened at this separating location. The tensile force required for the final separation can be applied differently. On the one hand, it is possible to apply this tensile force onto the rolling strip 4 itself; but there is also the possibility of maintaining the peripheral speed of the blade drum 11 somewhat smaller or somewhat greater than the feed rate of the rolling strip 4 so that the tensile force, which causes the tearing of the rolling strip 4, is effected between the blade 10
and the leading or trailing end of the rolling strip 4. However, there is also the possibility of configuring the speed differences or tensile force differences such that the separation is effected by them.
In the embodiment. the rolling strip 4 is removed from a coiler 9. The blade drum 11 provided with a wedge 10 rotates at the end of the lever arm 12. The eccentric 14 is actuated for carrying out the cut and pivots by means of the guide 13 the lever arm 12 as well as the blade drum 11 into their active position 15,
In its active position 15 the blade drum 11 bends the rolling strip 4 downwardly to the line 16 and the wedge 10 penetrates accordingly into the rolling strip 4, this being effected by the impact of the blade drum onto the mass of the rolling strip 4 as well as the forces resulting from movement of the rolling strip. The longitudinal forces, resulting from removal of the rolling strip 4 and/or from the rotation of the blade drum with partially penetrated wedge 10. separate the rolling strip 4.
The invention enables several variants . For example, as an advancing device hydraulic pistons engaging lever arms can be provided as well as hydraulic pistons which engage a linear guide. Eccentric devices are also possible which determine by means of a tab the pivot angle of a lever arm or whose eccentrics engage directly a guide of the lever arm. In any case, the desired wear reduction as well as the elimination of machining of the shear parts within narrow tolerances are made possible so that, in accordance with the object, a simply configured shear is provided which is exposed only to relatively minimal wear.
Lisc of Reference Numerals
2 . blade drum
3. anvil drum
4. rolling strip 5. 6. , 7.directional arrows
8. double arrow
11. blade drum
12. lever arm
15. operating position
1. Flying shear comprising at least one drum provided with a
blade, whose peripheral speed can be synchronized with the
feed rate of the rolling strip, and comprising an anvil
positioned opposite the drum,
that the mass of the rolling strip (4), accelerated by being pushed back by the blade drum (11), as well as the tensioning force of the deflected rolling strip (4) are used as the anvil,
2. Shear according to claim 1,
that the blade drum (11) is movable by an advancing device into the active position in which at least the blade (10) of the blade drum (11) is in cutting contact with the rolling strip (4).
3. Shear according to claim 1 or 2, characterized in
that in the active position of the blade drum (11) the cross-section of the rolling strip (4) is reduced by a partial penetration of the blade (10) such that a tearing of the rolling strip (4) at the weakened location is insured as a result of the longitudinal forces loading the rolling strip (4).
4. Flying shear substantially as herein described with reference to the accompanying drawings.
|Indian Patent Application Number||IN/PCT/2001/1429/CHE|
|PG Journal Number||02/2008|
|Date of Filing||16-Oct-2001|
|Name of Patentee||M/S. SMS DEMAG AG|
|Applicant Address||Eduard-Schloemann-Strasse 4, 40237 Dusseldorf,|
|PCT International Classification Number||B23D 31/00|
|PCT International Application Number||PCT/EP00/03168|
|PCT International Filing date||2000-04-10|