Field of the Invention
The present invention relates to an apparatus for cutting a blank metal sheet, in particular a thin copper sheet, into parallel adjacent strips and for stacking these strips in adjoining compartments separated by partitions, i.e. in a so-called cassette, from which the strips can be taken individually by, for example, a starting-sheet machine to equip the starting sheets of copper electrolysis with lugs so that the starting sheets can be suspended in the electrolytic tanks and be supported by the lugs and bars passing through the lugs.
There is a previously known apparatus for cutting lug sheets with a circular cutter into parallel adjacent strips which slide along an inclined surface into a cassette provided with partitions, the surface having longitudinal vertical walls for guiding the strips into the compartments separated by partitions in the cassette. Such an apparatus is, however, prone to disturbances. The cut strips tend to turn into a transverse position on top of the guide walls and the adjacent strips and then do not fall into the compartments in the cassette. This disadvantage is largely due to the fact that the edges of the strips, being somewhat uneven after the cutting, tend to cling to each other unless special measures are taken after the cutting to keep the edges of adjacent strips apart. Another cause of disturbances is the fact that the partitions are not longitudinally in alignment with the cutting points, and for this reason the strips have to move in the lateral direction before they can fall into the cassette. There is no gap in the lateral direction between the strips immediately after the cutting, whereas the distance in the lateral direction between the adjacent strips in the cassette is at least equal to the thickness of the partition. This necessitates the movement of the strips between the circular cutter and the cassette in a lateral direction. During this lateral movement the strips often turns into a transverse position and their edges tend to cling to each other.
The object of the present invention is to provide an apparatus, more reliable in operation than previous ones, for cutting a blank sheet into parallel adjacent strips and for directing the strips along an inclined slide surface fitted with longitudinal guide walls into a cassette divided into adjoining compartments by means of partitions.
Summary of the Invention
According to the present invention there is provided an apparatus for cutting a blank sheet into strips and for stacking these strips in adjoining compartments separated by partitions, the apparatus having lateral-transfer trays which extend, as seen in the direction of the feed, slightly forward and downward from the circular blades, are also inclined in the lateral direction and extend in the lateral direction from between two adjacent guide walls over one guide wall, at maximum as far as the vertical longitudinal plane running through the cutting point of one edge of the strip entering the lateral-transfer tray and at minimum through the vertical longitudinal plane which passes through the center point between the cutting points of the said strip, in order to slant the cut strips and to cause that edge which is inclined lower to slide along the adjacent guide wall, so that the upper edge can fall between the guide walls before the strip falls into the compartment.
Drawing
FIG. 1 is a view of a preferred form of the apparatus of the invention in perspective.
FIG. 2 is a detail view showing part of the shafts and blades employed in the apparatus of FIG. 1.
Preferred Embodiment
In FIG. 1, the complete circular cutter is indicated by 1, the downward-inclined slide surface following the circular cutter 1 is indicated by 2, and the complete cassette fitted after the slide surface 2 is indicated by 3.
The cassette has been divided by means of partitition walls 4 into compartments 5, the length of which correspond to the length of the cut strips and the width of which is determined by the width of the strips. The upper edge of the partitions 4 is above the plane which is a continuation of the slide surface 2, the partitions 4 continue on the slide surface 2 as longitudinal, vertical guide walls 6, the upper end of which is beveled and meets the upper edge 7 of the slide surface 2.
The circular cutter 1 has two shafts 8 and 9, fitted horizontally one above the other. Circular blades 10 have been mounted on each shaft at regular distances from each other in the axial direction so that the blades 10 on the upper shaft 8 slightly overlap the respective opposite blades 10 on the lower shaft 9. The shafts 8 and 9 have been fitted to rotate in opposite directions in order to cut the blank sheet fed between the blades 10 on the two shafts 8 and 9 into parallel adjacent strips and in order to feed the strips onto the inclined slide surface 2 between the guide walls 6.
Upon leaving the circular cutter 1 each cut strip falls onto a lateral-transfer tray, these trays extending in the longitudinal direction from the circular cutter 1 to approximately halfway down the inclined slide surface 2, and in the lateral direction each lateral-transfer tray 11 extends from the intersection between a guide wall 6 and the slide surface 2, in an upward-slanting direction, over the upper edge of the adjacent guide wall 6 and partly above the next interval between guide walls. Since the upper ends of the guide walls 6 are beveled, the inclination of the lateral-transfer trays 11 increase gradually towards their trailing edge 12.
The purpose of the lateral-transfer trays is, on the one hand, to keep the edges of adjacent strips apart so that the strips will not cling to each other, and on the other hand, to transfer the strips in the lateral direction so that each strip is directed to its respective interval between the guide walls and onwards into the compartment 5, one on top of the other. The strips thus gravitate away from each other and at the same time forwards each into its respective compartment 5 in the cassette 3. This lateral transfer is necessary even for the reason that, owing to the space taken by the thickness of the partitions, the spacing of the compartments 5 in the cassette 3 is wider than that of the blades 10 of the circular cutter 1. Thus the lateral-transfer trays 11 must be fitted so that they overlap slightly in the lateral direction, with the overlap increasing in the lateral direction (in the figure, on the left-hand side).
After the cutting the uneven edge strips fall over the external guide walls on the slide surface 2 to the opposite sides of the slide surface. For one of the edge strips there is an upward-directed plate 15 extending laterally from the respective external guide wall towards the slide surface 2, and the edge strips coming on it slide along it to the side.
For feeding the blank sheet and guiding the strips, there is, as shown in the detail view of FIG. 2, a smaller-diameter peripheral surface 13 on the side of each circular blade 10 on the upper shaft 8; together with an opposite circular blade at the corresponding point on the lower shaft 9 this surface 13 constitutes a point which presses the plate. Furthermore, the peripheral surface 13 of each circular blade 10 is coated with a resilient material 14 to produce a pressure contact for the sheet without damaging the sheet.
The inclination of the lateral-transfer trays 11 and the slide surface 2 is selected so that, under the effect of the momentum given to the strips by the circular cutter and gravity, the cut strips slide and fall automatically into the cassette 3. The feeding rate must, of course, be adjusted to allow for the cut strips to pass before the next strips enter on the slide surface 2.
Furthermore, the end 16 of the cassette 3 can be opened so that the stacks of strips in the compartments 5 can be removed from the cassette 3 and transferred to the starting-sheet machine for bending the strips and for attaching them to the starting sheets. Alternatively, the entire cassette can be transferred to the starting-sheet machine.