Two-roller driving device

#The present invention relates to a two-roller driving device associated with an underground reel in a rolling mill for band-shaped rolling material, especially a wide band rolling mill, which driving device comprises an upper and a lower driving roller which are journalled vertically one above the other. The axis of the upper driving roller is, viewed in the direction of movement of the band at the band inlet into the reel, located behind the axis of the lower driving roller and after grasping the start of the band is by means of the winding mandrel of the reel pivotable vertically above the axle of the lower driving roller and while therebehind a deviating device for the band is provided.

#Two-roller driving devices of the above mentioned type are known with which the axle of the upper driving roller is during the movement of the band pivotable from the position behind the axle of the lower driving roller into a position vertically above the axle of the lower driving roller. Such pivoting of the upper driving roller has proved advantageous for the winding of the bands. This known device, however, has the drawback that the upper driving roller can be pivoted merely between two positions which have to be fixed during the construction, and that the gap for the pressing-on pressure between the upper and lower driving roller changes during the pivoting operation. A further drawback consists in that with the heretofore known devices, the band can move only into the reel when the upper driving roller is pivoted toward the rear because only then the deviating device will engage the upper driving roller.

#There has furthermore become known a three-roller driving device which is associated with a reel for bandshaped rolling material and with guiding means for the incoming band end directed toward said reel. With this device, two of the driven rollers are located above the upper band side and are by a common carrier and through cylinder piston transmissions engaging the same variable as to height while occupying differently spaced positions from the driving roller below the band. With this heretofore known device, the carrier is arranged above the band and is designed as a coupling bar receiving the roller axles. The coupling bar has its ends respectively connected to piston cylinder transmissions which are adapted to be actuated individually and independently of each other. Also with this known driving device, it is not possible during the pivoting of the upper two driving rollers to maintain a precisely defined gap or precise pressing force between the rear upper driving roller and the lower driving roller. Furthermore, the distance between the last lower roller bed roller and the lower driving roller must be kept rather great which fact, with thin bands has an unfavorable effect upon the inlet movement of the band and causes disorders.

#These and other objects and advantages of the invention will appear more clearly from the following specification in connection with the accompanying drawings, in which:

#FIG. 1 illustrates a cross section of the device with driving rollers in a passing through position.

#FIG. 2 is a side view of FIG. 1 with driving rollers in their passing through position.

#The driving device according to the present invention is characterized primarily in that the upper driving roller is mounted in a stand which is pivotable about the axis of the lower driving roller toward the lower driving roller which is mounted in a frame, and is furthermore characterized in that a deviating flap which is horizontally displaceable in the frame is movably connected to the stand.

#According to a further development of the driving device according to the invention, the mounting of the stand is on the outside connected to an intermediate bushing into which are built the bearing bodies of the lower driving roller while the intermediate bushings are mounted in the frame and are held therein by bearing covers. The pivoting movement of the stand is limited by abutments which are connected to the frame. For adjusting the gap required between the upper and lower driving rollers, advantageously one air or hydraulic cylinder each is arranged on the stand on both sides thereof. This cylinder is through connecting rods directly connected to the inserts of the upper driving roller. Below the inserts, bearings in the form of wedge-shaped members are provided which are arranaged on a threaded spindle and are movable by means of a motor. For purposes of pivoting the stand and thereby the upper driving roller, advantageously in front of said stand, when viewing in the direction of movement of the band through the device, one hydraulic cylinder each is arranged on both sides. This cylinder is pivotally arranged on the frame and its connecting rod is joined to the stand. In this way, by a simple interruption of the supply of liquid to the hydraulic cylinders, the stand can be held stationary in any position between the two outer layers.

#According to a further development of the invention, an oblong hole guiding means is provided in the frame, in the direction of movement of the band through the device, behind the lower driving roller, for mounting and guiding a roller bed roller. On the bearing body of the roller bed roller there is journalled a pivotable flap which is adapted to be controlled by means of a lever system which is connected to a stand. To this end, one end of the first lever is linked to the stand, whereas the other end is linked to the second lever. The second lever, the other end of which is journalled in the bearing body of the roller bed roller, is pivotable about a connecting point on the frame.