Abstract
In a sheet processing method for sheets of paper or cardboard, a sheet for processing is, in the processing station, firstly brought to a standstill and then set down, whereas the processed sheet is, in the output station, set down from a moving state. A punching or stamping machine has an input station, a processing station and an output station arranged one behind the other in a sheet transport path, and a sheet gripping device which is designed to set down a sheet for processing in the processing station when the sheet gripping device has come to a standstill in a second reversal position, and to set down a processed sheet in the output station as the sheet gripping device approaches the second reversal position.
Claims
1. A sheet processing method for sheets of paper, cardboard, plastic or the like, the processing method including an input station for the provision of sheets for processing, a processing station for processing a sheet arranged therein, and an output station for the setting-down of processed sheets which are provided one behind the other in a sheet transport path, and a sheet transport device movable between a first reversal position and a second reversal position along a sheet transport path and, repeatedly in series, gripping in the input station, a sheet for processing, gripping in the processing station, a processed sheet, moving the sheet for processing from the input station into the processing station and releasing said sheet for processing, moving the processed sheet from the processing station into the output station substantially simultaneously with the moving of the sheet for processing and releasing the processed sheet, and processing the sheet for processing in the processing station, wherein the sheet for processing is, in the processing station, firstly brought to a stop and then released, and the processed sheet is, in the output station, released while still moving, wherein release of the processed sheet occurs before release of the sheet for processing.
2. The sheet processing method as claimed in claim 1, in which, in the output station, a conveyor which operates continuously at a conveying speed facilitating the onward transport of a sheet, wherein the processed sheet is released onto the conveyor.
3. The sheet processing method as claimed in claim 2, in which the sheet for processing and the processed sheet are moved at a transport speed which, at least during the releasing of the processed sheet in the output station, is substantially equal to the conveying speed of the conveyor.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
(1) The invention will be discussed in more detail below on the basis of an exemplary embodiment and associated drawings, in which FIGS. 1 to 8 show different method steps on a punching or stamping machine.
DETAILED DESCRIPTION
(2) The punching or stamping machine 1 illustrated in FIGS. 1 to 8 comprises a discontinuously operating input station 11, a discontinuously operating processing station 12, and a continuously operating output station 13. Laterally adjacent to the input station, the processing station and the output station, and thus parallel to a sheet transport path along which sheets are moved through the punching or stamping machine, there extends a sheet transport device which is designed for gripping, moving and releasing two sheets, which sheet transport device has a linear guide arranged parallel to a sheet transport path and has a sheet gripping device, which sheet gripping device is movable back and forth along the linear guide between a first reversal position and a second reversal position and has a common base rail, which in the exemplary embodiment is the lower rail, and two separately activatable gripping elements, which in the exemplary embodiment are partial rails of the upper rail, which gripping elements interact with the common base rail in order to grip in each case one sheet at a lateral edge.
(3) Laterally adjacent to the punching or stamping machine 1 in the region of the input station 11, there is arranged a sheet stack 4 by means of which the sheets for processing are provided to the machine and fed individually to the input station 11.
(4) In FIG. 1, the sheet gripping device is arranged in a first reversal position, in which a first gripping element 21 for gripping a sheet for processing 31 is positioned in the input station 11 and a second gripping element 22 for gripping a processed sheet 32 is positioned in the processing station 12. Those gripping elements 21, 22 are open and are thus ready to grip a respective sheet 31, 32.
(5) FIG. 2 shows how a sheet for processing 31 is removed from the sheet stack 4 and moved transversely with respect to the sheet transport path into the input station 11, whereas, in the processing station 12, an already-processed, that is to say stamped or punched, sheet 32 is situated such that it can be gripped by the second gripping element 22. In FIG. 3, the sheet for processing 31 has also come to a standstill in the input station 11, such that it can be gripped by the first gripping element 21.
(6) FIG. 4 shows how the first gripping element 21 grips the sheet for processing 31 lying in the input station 11, and the second gripping element 22 grips the processed sheet 32 lying in the processing station 12. The gripping occurs simultaneously by virtue of both gripping elements 21, 22 being simultaneously closed by means of a common actuating device, such that both sheets 31, 32 are gripped at a lateral edge, that is to say an edge running parallel to the sheet transport path.
(7) FIG. 5 shows how the sheet gripping device is, with the closed gripping elements 21, 22 and with the two sheets 31, 32, moved from the first reversal position in the direction of the second reversal position. FIG. 6 illustrates how the second gripping element 22 is opened by means of a separate actuating device and sets down the processed sheet 32 on a continuous conveyor arranged in the output station 13, which conveyor moves at the same speed as the sheet gripping device as the sheet gripping device approaches the second reversal position, that is to say already before the second reversal position is reached. From this point in time onward, only the sheet for processing 31 is moved by the first gripping element 21 of the sheet gripping device, whereas the processed sheet 32 is moved onward by the continuous conveyor.
(8) FIG. 7 shows the moment at which the sheet gripping device reaches the second reversal position and comes to a standstill there. The first gripping element 21 sets down the sheet for processing 31 in the processing station 12 by virtue of the first gripping element 21 being opened by means of a separate actuating device. Both gripping elements 21, 22 are now open, and the processed sheet 32 is moved onward by the continuous conveyor arranged in the output station 13.
(9) As shown in FIG. 8, the processed sheet 32 exits the punching or stamping machine 1 on the conveyor, for example in order to be fed to a breakaway station, while the sheet gripping device with the two gripping elements 21, 22 is moved back into the first reversal position and the sheet for processing 31 is processed, that is to say punched or stamped, in the processing station 12. The described steps are subsequently repeated again.
