Search

DE-102024132883-A1 - Method and apparatus for capturing a number of corrugated cardboard sheets

DE102024132883A1DE 102024132883 A1DE102024132883 A1DE 102024132883A1DE-102024132883-A1

Abstract

Method for detecting a number of corrugated cardboard sheets in a stack, comprising: - Sensory detection of surface modulation of a scale stream, - Determining the number of corrugated cardboard sheets based on the measured surface modulation, and - Output of the number of corrugated cardboard sheets. The proposed solution also includes a device for capturing a number of corrugated cardboard sheets in a stack, a computer program product, and a corrugated cardboard plant.

Inventors

  • Jonas Bäuml
  • Florian Wolf
  • Thomas REICHL

Assignees

  • BHS CORRUGATED MASCHINEN- UND ANLAGENBAU GMBH

Dates

Publication Date
20260513
Application Date
20241111

Claims (15)

  1. Method for detecting the number of corrugated sheets (109) in a stack, comprising: - sensorial detection of a surface modulation (214) of a shingle stream, - determining the number of corrugated sheets (109) based on the detected surface modulation (214), and - outputting the number of corrugated sheets.
  2. Procedure according to Claim 1 , characterized in that the surface modulation (214) is carried out with a time-resolved distance measurement from a reference point to a measuring area on the surface of the scale stream.
  3. Procedure according to Claim 1 or 2 , characterized in that , to determine the number of corrugated cardboard sheets (109), joints of the scaled corrugated cardboard sheets (109) are identified in the surface modulation (214).
  4. Procedure according to one of the Claims 1 until 3 , characterized in that an arc current is determined based on a number of impacts of the shingled corrugated sheets (109) passing a predetermined location per unit of time.
  5. Procedure according to Claim 4 , characterized in that the number of corrugated cardboard sheets (109) in a stack is determined by time integration of the sheet flow.
  6. Method according to a preceding claim, characterized in that a surface modulation (214) of a scale stream is detected in a plurality of measuring ranges.
  7. Method according to a preceding claim, characterized in that, when the detected number of corrugated cardboard sheets (109) corresponds to a target number, the stack is transported out.
  8. Method according to a preceding claim, characterized in that a stack height (197) is detected.
  9. Procedure according to Claim 8 , characterized in that a lowering speed of the lifting table (194, 195) is controlled based on the stack height (197).
  10. Device (200) for detecting a number of corrugated board sheets (109) in a stack, comprising: - at least one detection device (210, 211, 212) for detecting a surface modulation (214) of a shingle stream, - an output device (220) for dispensing a number of corrugated board sheets (109), and - a control unit (230) connected to the at least one detection device (210, 211, 212) and the output device (220), which is configured to determine a number of corrugated board sheets (109) based on the detected surface modulation (214) and to dispense them via the output device (220).
  11. Device (200) according to Claim 10 , characterized in that the at least one detection device (210, 211, 212) is equipped with a sensor designed for distance measurement.
  12. Device (200) according to Claim 10 or 11 , characterized in that the at least one detection device (210, 211, 212) is set up to measure a surface modulation (214) in different measuring ranges.
  13. Device (200) according to one of the Claims 10 until 12 , characterized in that the device (200) is for carrying out a method according to one of the Claims 1 until 9 is set up.
  14. Computer program product comprising machine-readable instructions which direct the control unit (230) of a device (200) according to one of the Claims 10 until 13 during execution, initiate a procedure according to one of the Claims 1 until 9 to carry out.
  15. Corrugated board plant (100) for the production of corrugated board laminated on at least one side with a device (200) according to one of the Claims 10 until 13 .

Description

The proposed solution relates to a method for detecting a number of corrugated cardboard sheets in a stack and a device set up for this purpose. Methods and devices for counting the number of corrugated board sheets are known in the corrugated board manufacturing industry. The aim of such methods and devices is to determine, at least approximately, how many corrugated board sheets are in a stack. For example, the number can be determined based on the cutting signals sent by a cross-cutter of a corrugated board machine. However, this approach can lead to unsatisfactory results. If, for example, sample sheets are removed by the operating personnel and non-destructive quality control checks are carried out, the number determined by the cross-cutter's cut count may differ from the actual number in the stack. Similarly, errors during the cutting process can cause the actual number to differ from the number determined by the cross-cutter. Therefore, there is a need to improve methods and devices for capturing a number of corrugated cardboard sheets. This problem is solved by the method according to claim 1 and a device according to claim 10. The proposed method for picking up a number of corrugated cardboard sheets in a stack therefore comprises at least the following steps: - Sensory detection of surface modulation of a scale stream, - Determining the number of corrugated cardboard sheets based on the measured surface modulation, and - Output of the number. Sensory detection of surface modulation and determination of the number of corrugated board sheets based on this detection can enable the determination, and in particular the automatic determination, of the number of sheets independent of production parameters. Therefore, the proposed method can determine and correctly output the actual number of corrugated board sheets even if the number of finished corrugated board sheets transported to a stacking tray per unit of time (sheet flow) is unexpectedly changed or altered by external interventions. The term "finished" in this context can mean that an endless web of corrugated board has been repeatedly cut in a cross-cutting unit, perpendicular to the conveying direction, to obtain the individual sheets or panels. These sheets are then transported via a conveying device, such as a conveyor belt, to the stacking tray, where they are arranged in a stack. During transport, the sheets lie adjacent to each other along the conveying direction, but are not necessarily arranged in a regular pattern. Typically, adjacent sheets overlap on the conveying device, resulting in a so-called shingle pattern. The sheets arranged on the conveying device thus have a top and bottom surface along the vertical direction. Due to the aforementioned arrangement of the sheets, both surfaces generally have a continuous but uneven surface (surface modulation). Uneven surface means that each of the two surfaces has flat sections that are angled relative to each other, particularly obtusely angled ones. If individual corrugated sheets are removed from the sheet flow before stacking, or if the number and/or density of the sheets on the conveyor deviates from a predicted number and/or density, this is reflected in a spatial change in the surface modulation. During operation of the conveyor, this also leads to a temporal change in the surface modulation. These changes can be automatically taken into account with the proposed method. In particular, it can automatically account for deviations in the sheet flow from a sheet flow assumed based on production parameters, such as the removal of sample sheets or production errors like cutting errors. This allows the system to determine how many sheets reach a stacking tray at any given time and, consequently, how many sheets have already been stacked. The number of stacked sheets can be assigned to the stack after stacking is complete, enabling the customer to be informed of the correct number of sheets in a stack. Furthermore, by evaluating the actual number of sheets (i.e., the number determined by the proposed method) and the number of cuts made by the cross-cutter, defective cuts can be identified. This allows the cutting reliability of the cross cutter to be determined automatically. This, in turn, enables the automated detection of maintenance needs on the cross cutter. The output of a specific number of corrugated cardboard sheets can be indicated by an analog and/or digital signal. For example, output can be indicated by a visual and/or audible signal, through which Operators can be informed about the number of corrugated cardboard sheets in a stack. This can enable them to selectively end a stacking operation or assign a number of stacked corrugated cardboard sheets to a specific stack. Alternatively or additionally, the output of the count can include sending a control signal to a monitoring device or control unit, e.g., the stacking unit. This allows a stacking process to be controlled. The con