Sheet processing machine

Abstract

Sheet processing machine (10) with a jam detection device (44, 46) comprising a light emitting element and a light receiving element forming a light barrier in a detection area (53, 78) of a processing station of the sheet processing machine (10). The jam detection device (44, 46) further comprises a control unit (48) connected to the light receiving element and adapted to register in case the light barrier is interrupted.

Description

Technical Field

[0001] This invention relates to a sheet processing machine with a jamming detection device. Background Technology

[0002] Sheet processing machines, also known as conversion machines, are used in the packaging industry to process raw materials such as cardboard, paper, or foil into intermediate or final products, typically in sheet form. Conversion operations can include, for example, printing, cutting, creasing, blanking, stamping, and / or folding / adhesive bonding. Typically, these operations are completed in subsequent processing stations of the sheet processing machine, where the sheet is conveyed from one station to the next via a transport mechanism. After conversion in a designated stacking area of ​​the sheet processing machine, the sheets can be collected into vertical stacks.

[0003] Modern sheet processing machines are capable of high sheet throughput, i.e., high processing speeds. However, high processing speeds increase the risk of sheets or portions of sheets getting stuck in one of the processing stations of the sheet processing machine. For example, blanking operations involve using a blanking tool to break the notches in the sheet (which have already been formed in previous processing steps), thereby pushing the blank downwards into a stacking area for collecting blanks. If the sheet or any blank gets stuck in the blanking tool or stacking area, further operation of the processing machine can result in the production of an entire batch of damaged blanks, or at least blanks of degraded quality. Summary of the Invention

[0004] The object of this invention is to provide a device for reliably detecting jamming in a machining machine. Preferably, the device should be simple and inexpensive.

[0005] US2007 / 012204 discloses a jam detection system located at the output of a rotary printing press, which has two beams of light for detecting the front side of the sheet, and a system for checking the correct travel of the sheet to detect possible jamming. It does not use a light curtain.

[0006] The objective of this invention is achieved by a sheet processing machine equipped with a jamming detection device, which includes a light emitting element and a light receiving element, forming a grating within the detection area of ​​the processing station of the sheet processing machine. The jamming detection device further includes a control unit connected to the light receiving element and adapted to record when the grating is interrupted.

[0007] A grating is a simple and cost-effective option for detecting the presence of any sheet, blank, or portion thereof along the detection region of the grating. Furthermore, the signal received from the light-receiving element is a reliable measurable parameter.

[0008] Furthermore, the response time of the optical receiving element can be low enough to distinguish between grating interruptions caused by normal operation of the sheet processing machine (e.g., a billet being pushed through the detection zone of the billet separation station) and interruptions caused by jammed sheets, billets, and / or portions thereof. Specifically, the duration for which jammed sheets, billets, and / or portions thereof are expected to interrupt the grating is much longer than the time it takes for the sheet or billet to pass through the detection zone during normal operation of the sheet processing machine.

[0009] The grating formed by the light emitting element and the light receiving element in the detection area is a light curtain that includes more than one light source, and the control unit is adapted to record when one or more light sources are interrupted.

[0010] In this example, the light emitting element includes more than one light emitting source, and the light receiving element includes more than one light receiving sensor, wherein each light receiving sensor is associated with one of the light emitting sources.

[0011] The light curtain allows the control unit to record any interruptions to the light curtain in a spatially resolved manner. In other words, the control unit can obtain spatially resolved information about any object within the detection area.

[0012] Depending on the number of light emitting sources and light receiving sensors, the size of the detection area, and the spacing between the associated pair of light emitting sources and light receiving sensors, a light curtain can be a substantially continuous light curtain.

[0013] To enhance the reliability of the jamming detection equipment, the light curtain can extend beyond at least 80% of the width of the detection area, particularly at least 90% of the width of the detection area. Preferably, the light curtain extends substantially beyond the entire width of the detection area to ensure that no sheet, blank, and / or portion thereof can exist in the detection area without being recorded by the control unit.

[0014] To provide a simple arrangement for aligning the light emitting element and the light receiving element, the light receiving element and the light emitting element can be mounted on a first track and a second track, respectively, with the first track and the second track being parallel to each other.

[0015] In one variation, the detection area is positioned below a support for collecting sheets or blanks processed by a sheet processing machine.

[0016] The support can be a non-stop support, also referred to as a "non-stop" support. Such a non-stop support typically consists of a series of telescopic rods, also known as "swords," which are laterally spaced from each other. Due to the gaps created between the telescopic rods, there is a risk that sheets or blanks that should be stacked on the non-stop support may become stuck between the rods. In this case, if the detection area is below the support, a jamming detection device can record the interruption of the grating. In other words, the jamming detection device can monitor whether the sheets or blanks are correctly positioned on the support.

[0017] The processing station may include tools that are at least partially arranged within the inspection area, wherein the control unit includes a storage module for storing information about the tools.

[0018] The risk of objects getting stuck is higher at the tooling station because the tool interacts with the sheet being processed in the sheet processing machine. Any misalignment and / or malfunction of the tool can therefore cause the sheet, blank, or part of it to get stuck in the sheet processing machine.

[0019] Preferably, the information about the tool includes a light blocking diagram, which indicates whether the grating is interrupted by the tool, and in particular whether one or more light rays are interrupted by the tool.

[0020] In other words, the ray blocking map represents the geometry of the portion of the tool arranged within the detection area. Since the control unit knows the tool's geometry based on the ray blocking map, interruptions in the grating, especially interruptions in one or more rays caused solely by the presence of the tool, can be easily identified by the control unit. This allows for a reliable distinction between interruptions originating from the tool and interruptions from objects stuck within the detection area.

[0021] In order for the control unit to distinguish between different tools, information about the tools can include tool identifiers.

[0022] Tool identifiers can be determined by scanning labels (such as RFID tags, barcodes, and / or QR codes).

[0023] The jamming detection device may include a detection apparatus adapted to scan the type of label used for the tool.

[0024] The tools used in sheet metal processing machines typically need to be changed between different processing jobs to accommodate the necessary conversion operations for each job. By providing a tool identifier for each tool used, the control unit can automatically identify the light obstruction map stored in the memory module based on the relevant tool.

[0025] To ensure that an associated light blocking map can be obtained for each tool used in the processing station, if the tool identifier is not already stored in a storage module with an associated light blocking map, the control unit can be adapted to automatically determine the light blocking map of the tool.

[0026] This means that the control unit can automatically determine the light-blocking pattern without any intervention from the sheet processing machine operator, where previously unknown tool identifiers become associated with the determined light-blocking pattern.

[0027] To acquire information about the tool, the control unit can be switched to learning mode. Preferably, the automatic determination of the light obstruction pattern is performed in learning mode.

[0028] This tool is especially important for blanking tools. During blanking operations, the risk of objects getting stuck in the corresponding blank separation station is particularly high, as the blank must be successfully separated from the processed sheet. Therefore, monitoring the proper functioning of the blanking tool is particularly important for preventing interruptions in the operation of sheet processing machines.

[0029] To provide the sheet processing machine operator with information about the current status of the sheet processing machine, the sheet processing machine may include a human-machine interface, such as a touch-sensitive display, connected to the control unit.

[0030] Preferably, if the grating is interrupted, the control unit is adapted to transmit a warning message to the human-machine interface, particularly wherein the warning message is transmitted only if the interruption of the grating does not correspond to a light-blocking map of the tool stored in the storage module.

[0031] The warning message can also include the exact location of the interrupted grating in the detection area to make it easier to identify objects stuck in the detection area.

[0032] Tool information, particularly tool identifiers, can be displayed on the human-machine interface to allow the operator to check that the correct tools are installed. Tool identifiers can also be provided by the operator and transmitted to the control unit.

[0033] In addition, when the control unit is in learning mode, a message can be displayed on the human-machine interface to notify the operator that additional information about the installation tools is needed. Attached Figure Description

[0034] Further advantages and features of the invention will become apparent from the following description of the invention and the accompanying drawings, which illustrate non-limiting illustrative embodiments of the invention, wherein:

[0035] - Figure 1 A sheet processing machine according to the present invention is illustrated schematically;

[0036] - Figure 2 Schematic illustration of the work by Figure 1 A top view of the sheet processed by the sheet processing machine;

[0037] - Figure 3 It shows in Figure 1 A perspective view of the jamming resistance detection equipment used in a sheet metal processing machine.

[0038] - Figure 4 It shows Figure 3 Another perspective view of the jamming detection device, showing the tools arranged in the detection area of ​​the device.

[0039] - Figure 5 It shows Figure 4 The front view of the card resistance detection device, and

[0040] - Figure 6 A perspective view of another card resistance detection device is shown. Figure 1 Support frame for medium sheet processing machine. Detailed Implementation

[0041] Figure 1 A sheet processing machine 10 is schematically shown, which is capable of cutting blanks 11 from a series of sheets 12 (see...). Figure 2 These blanks 11 are typically used for subsequent folding and gluing to form a packaging box. However, the sheets 12 may typically be made of paper, cardboard, foil, composites of these materials, or any other material commonly used in the packaging industry.

[0042] The sheet processing machine 10 comprises a series of parallel but interdependent processing stations forming a unified assembly. The machine 10 includes a loading station 14, followed by a cutting station 16 (also commonly referred to as a stamping station), including, for example, a die press or platen press 18, where the sheet 12 is converted by cutting; a waste removal station 20, where most of the waste is stripped off; a blanking separation station 22 (also commonly referred to as a receiving station) for separating the blank 11 by a blanking tool 23 (or blanking operation); and for the remaining waste sheet 25 (see [see image]) of the sheet 12 to be stamped. Figure 2 ) Cleared drainage station 24.

[0043] The number and nature of the processing stations can vary depending on the nature and complexity of the conversion operations to be performed on the sheet 12.

[0044] The sheet processing machine 10 also has a conveying mechanism 26, which is a conveying device in the illustrated embodiment, to be able to move each sheet 12 individually from the outlet of the loading station 14 to the emptying station 24.

[0045] The conveying device uses a series of clamping rods 28, which are mounted to be movable by means of two loops of chain 30, with one loop of chain 30 placed laterally on each side of the sheet processing machine 10. Each loop of chain 30 travels in a circle to allow the clamping rods 28 to follow a trajectory that passes sequentially through the cutting station 16, the waste removal station 20, the billet separation station 22, and the emptying station 24.

[0046] Each gripping lever 28 moves outward along a substantially horizontal plane in the channel between the driven wheel 32 and the idler wheel 34, and then moves back along a return path at the top of the sheet processing machine 10. Once back to the driven wheel 32, each gripping lever 28 is able to grip a new sheet 12 at the leading edge of the sheet 12.

[0047] exist Figure 1 In the diagram, each processing station is shown in the form of two rectangles, representing the top and bottom portions of each side of the motion plane of the sheet 12, respectively.

[0048] exist Figure 1 In this system, the horizontal (or lateral), longitudinal, and vertical directions are represented by orthogonal spatial systems (T, L, V).

[0049] The terms "upstream" and "downstream" are relative to areas located in... Figure 1 The direction of movement of sheet 12 is defined by the processing direction indicated by the middle arrow D.

[0050] exist Figure 2 The image shows a sheet being processed by sheet processing machine 10 (see image 10). Figure 1 The current state and shape of the processed sheet 12, wherein according to Figure 1 A top view of the processing stations of the sheet processing machine 10 arranged in sequence.

[0051] In loading station 14, sheet 12 is configured as a flat sheet with a rectangular or quadratic surface.

[0052] In the cutting station 16, the profile of the blank 11 is prepared by forming a weakened edge 38 in the sheet 12, for example, by a series of notches and / or perforations.

[0053] In the waste removal station 20, a selected portion of the sheet 12 (such as...) Figure 2 The shaded area 40 (shown in the middle) is cut out and discharged from the sheet 12.

[0054] Finally, the blank 11 is separated from the sheet 12 in the blank separation station 22, so that a blank 11 with two cross shapes having a central opening 42 is obtained from the sheet 12 of the illustrated embodiment.

[0055] The remaining portion of sheet 12, i.e., residual waste sheet 25, is removed from the emptying station 24.

[0056] certainly, Figure 2 The order shown is merely illustrative in nature. Different shapes and sizes of sheet 12 and / or blank 11 can be used and formed by sheet processing machine 10, depending on the type of sheet 12 used and the processing station provided by sheet processing machine 10.

[0057] Back Figure 1 The sheet processing machine 10 also includes a first jamming detection device 44 and a second jamming detection device 46 in the billet separation station 22.

[0058] In principle, only a single jamming detection device 44 or 46 can be used. In addition, the jamming detection device 44 can be placed on any processing station of the sheet processing machine 10, depending on which position is the most important and / or the most suitable position for monitoring whether the sheet 12, blank 11 or a portion thereof is jammed.

[0059] The first card resistance detection device 44 and the second card resistance detection device 46 are connected to the control unit 48, for example, via an Ethernet connection. However, the first and second card resistance detection devices 44 and 46 can also be connected to the control unit 48 by any means that provides sufficiently fast signal exchange between the first and second card resistance detection devices 44 and 46 and the control unit 48, respectively. For example, this connection can also be established wirelessly, for example, via Wi-Fi.

[0060] In principle, each of the first and second jamming detection devices 44 and 46 can have its own control unit 48 associated with the corresponding jamming detection device 44 and 46.

[0061] The control unit 48 includes a storage module 50 for storing information about the unloading tool 23.

[0062] The first jamming detection device 44 is positioned close to the unloading tool 23, such that the unloading tool 23 is partially positioned within the first detection area 53 of the first jamming detection device 44 (see...). Figure 3 )Inside.

[0063] The second jamming detection device 46 is arranged below the bracket 54, which in the illustrated embodiment is a non-stop bracket. More specifically, the second jamming detection device 46 is arranged on a series of telescopic rods 55 of the bracket 54 (see also...). Figure 6 Below ).

[0064] The control unit 48 is further connected to the human-machine interface 52, which in the illustrated embodiment is a touch-sensitive display.

[0065] Through the human-machine interface 52, the operator of the sheet processing machine 10 (not shown) can understand the current status of the sheet processing machine 10 and control the operation of the sheet processing machine 10.

[0066] exist Figure 3 The image shows a perspective view of the first card resistance detection device 44.

[0067] The first blocking detection device 44 includes a first track 58 and a second track 60, wherein the first track 58 includes an integrated (i.e., not explicitly shown) light emitting element and the second track 60 includes an integrated (i.e., not explicitly shown) light receiving element.

[0068] The light emitting element has multiple light emitting sources, specifically multiple laser emission spots, while the light receiving element has multiple light receiving sensors, each of which is associated with one of the light emitting sources. This arrangement between the first track 58 and the second track 60 forms a substantially continuous light curtain 62 composed of a large number of individual light rays.

[0069] In addition, the light curtain 62 is arranged in the first detection area 53 of the billet separation station 22 and extends substantially beyond the entire size of the first detection area 53.

[0070] The first track 58 and the second track 60 are respectively installed on the first frame 66 and the second frame 68. The first and second frames 66 and 68 are installed on the billet separation station 22.

[0071] Therefore, the first jamming detection device 44 can be reinstalled on the existing sheet processing machine 10.

[0072] Alternatively, the first and second frames 66 and 68 may also be part of the billet separation station 22, to which the first and second tracks 58 and 60 are mounted.

[0073] Figure 4 Another perspective view of the first card resistance detection device 44 is shown.

[0074] exist Figure 4 In the middle, the unloading tool 23 is partially arranged in the first detection area 53 of the billet separation station 22.

[0075] Figure 4 The blanking tool 23 shown is a bottom blanking tool, consisting of longitudinal and transverse bars 70 forming a grid. The blank 11 can fall through the gaps 72 of this grid and accumulate vertically on the support 54 (see...). Figure 1 ).

[0076] Figure 5 It shows Figure 4 The front view of the first card resistance detection device 44.

[0077] from Figure 5 It can be seen more clearly that the blanking tool 23 passes through the light curtain 62 by means of the first protrusion 74 and the second protrusion 76. The number and arrangement of the first and second protrusions 74 and 76 are... Figure 4 and Figure 5 Features of the blanking tool 23 shown.

[0078] exist Figure 6 The image shows a perspective view of the second card resistance detection device 46.

[0079] The second card resistance detection device 46 is substantially the same as the first card resistance detection device 44. Components that are identical or have the same function are provided with the same reference numerals.

[0080] The second blocking detection device 46 also includes a first track 58 and a second track 60, wherein the first track 58 includes an integrated (i.e., not explicitly shown) light emitting element and the second track 60 includes an integrated (i.e., not explicitly shown) light receiving element.

[0081] The light emitting element has multiple light emitting sources, particularly multiple laser emission spots, while the light receiving element has multiple light receiving sensors, each of which is associated with one of the light emitting sources. This arrangement forms a substantially continuous light curtain 62 between the first track 58 and the second track 60.

[0082] In addition, the light curtain 62 is set in the second detection area 78 of the material discharge separation station 22 and extends beyond most of the second detection area 78.

[0083] The second detection area 78 is located below the support 54, and more specifically, below the storage area 80 formed on the upper side of the telescopic rod 55 of the support 54. The telescopic rod 55 is movable between the working position and the resting position, such as... Figure 6 The double arrow P is shown in the diagram.

[0084] exist Figure 6 The diagram shows the working position of the telescopic rod 55, that is, the position where the telescopic rod 55 extends from the first paper impactor 84 of the support 54 to the second paper impactor 86.

[0085] Next, the operation of the first and second blocking detection devices 44 and 46 is described in more detail.

[0086] During the setup of the sheet processing machine 10 for a given processing operation, the operator of the sheet processing machine 10 installs the blanking tool 23 required for the desired blanking operation in the blank separation station 22.

[0087] As previously stated, as long as the blanking tool 23 remains installed in the billet separation station 22, the first and second protrusions 74 and 76 (see Figure 4 and Figure 5 This will interrupt multiple light rays between the light emitting element and the light receiving element of the first blocking detection device 44.

[0088] This causes a change in the sensor signal of the light receiving sensor associated with the interrupted light. Typically, in this situation, the intensity of the sensor signal drops to zero or to the noise level of the light receiving sensor.

[0089] In order for the control unit 48 to take into account these interrupted light rays, information about the tools used in the material separation station (i.e., about the installed material cutting tool 23) is stored in the storage module 50 of the control unit 48.

[0090] Information about the blanking tool 23 includes a tool identifier. The tool identifier can be provided to the control unit 48 by the operator of the sheet processing machine 10 or by scanning a tag (e.g., an RFID tag, not shown) on the blanking tool 23.

[0091] In addition, information regarding the blanking tool 23 includes a light blocking diagram. The light blocking diagram defines which rays of light from the light curtain 62 of the first jamming detection device 44 are expected to be interrupted by the first and second protrusions 74 and 76 of the blanking tool 23.

[0092] If the tool identifier of the blanking tool 23 is not present in the storage module 50, the control unit 48 enters learning mode. In learning mode, the control unit 48 calculates the light obstruction map of the currently installed blanking tool 23, associates it with the tool identifier, and stores it in the storage module 50. This process is completed automatically by the control unit 48, meaning the operator of the sheet processing machine 10 does not need to provide the light obstruction map.

[0093] If the tool identifier of the blanking tool 23 already exists in the storage module 50, the control unit 48 compares the light blocking map with the currently interrupted light. If any inconsistency is found, an error message is sent to the human-machine interface 52 to notify the operator of the sheet processing machine.

[0094] If the blanking tool 23 does not provide a tool identifier, the control unit 48 is adapted to compare the currently interrupted ray with a ray blocking map stored in the storage module 50. If a matching ray blocking map is found, the relevant tool identifier can be transmitted to the human-machine interface 52 so that the operator can check whether the tool identifier is correct. If no matching ray blocking map is found, the control unit 48 generates a tool identifier, associates the tool identifier with the ray blocking map, and sends a message to the human-machine interface 52 that a new tool has been identified.

[0095] Therefore, during the setup of the sheet processing machine 10, the control unit 48 can automatically identify the light source of the blanking tool 23 being used and the light curtain 62 in the first detection area 53 that is expected to be interrupted by the blanking tool 23. Simultaneously, any discrepancies can be immediately reported to the operator of the sheet processing machine 10 during the setup process to avoid any errors in the processing operation.

[0096] from Figure 6 It can be seen that the bracket 54 does not interrupt any light from the light curtain 62 arranged in the second detection area 78. Therefore, it is not necessary to define a light blocking diagram for the second blocking detection device 46. However, the control unit 48 can still generate a light blocking diagram indicating that the light from the light curtain 62 arranged in the second detection area 78 is not blocked by the bracket 54.

[0097] During the operation of the sheet processing machine 10, the first and second jamming detection devices 44 and 46 are used to monitor whether any object is stuck in or trapped in the first and / or second detection areas 53 and 78, respectively.

[0098] Such objects are particularly likely to be sheet 12, blank 11 and / or portions thereof, for example, they are trapped by the grid of blanking tool 23 (see Figure 4 ), or they are in bracket 54 (see Figure 6 The telescopic rod 55 slides between and locks in this position.

[0099] If an object gets stuck in the blank separation station 22, the entire sheet processing machine 10 must be stopped, because further operation will result in the production of blanks 11 that do not meet quality standards. In addition, the parts of the blank separation station 22 may be damaged by the stuck object.

[0100] However, if an object is stuck in the first and / or second detection areas 53 and 78 respectively, the light from the corresponding light curtain 62 at the object's location is interrupted, causing a change in the sensor signal transmitted by the light receiving sensor associated with the interrupted light.

[0101] This change in the sensor signal is registered by the control unit 48 so that the control unit 48 can send a warning message to the human-machine interface 52 to notify the operator of the sheet processing machine 10 that an object is stuck in at least one of the detection areas 53 and 78.

[0102] The warning message preferably includes the location of the interrupted light. Based on this, the operator can stop the operation of the sheet processing machine 10 and remove the jammed object.

[0103] Typically, it is also possible that the operation of the sheet processing machine 10 will automatically stop once the control unit 48 records any interruption in the light curtain 62.

[0104] Furthermore, the minimum interruption time can be stored in the storage module 50 of the control unit 48, and the control unit 48 is adapted to only transmit warning information to the human-machine interface and / or stop the operation of the sheet processing machine 10 if the interrupted light persists for at least the minimum interruption time. This allows for more reliable detection and minimizes erroneous warning messages and / or unnecessary shutdowns of the sheet processing machine 10.

[0105] The sheet processing machine 10 according to the present invention provides a simple and reliable device for detecting objects stuck in the blank separation station 22.

Claims

1. A sheet processing machine equipped with jamming detection devices (44, 46), The jamming detection device (44, 46) includes a light emitting element and a light receiving element, used to form a grating in the detection area (53, 78) of the processing station of the sheet processing machine (10), wherein the detection area (53, 78) is arranged below the support (54) for collecting the sheet (12) or blank (11) processed by the sheet processing machine (10). The jamming detection devices (44, 46) further include a control unit (48) connected to the light receiving element and adapted to record in the event that the grating is interrupted. Its features are, The grating formed by the light emitting element and the light receiving element in the detection area (53, 78) is a light curtain (62) comprising more than one light ray, and the control unit (48) is adapted to record in the event that one or more of the light rays are interrupted.

2. The sheet processing machine according to claim 1, wherein the light receiving element and the light emitting element are respectively mounted on the first track (58) and the second track (60).

3. The sheet processing machine according to claim 2, wherein the first track (58) and the second track (60) are parallel to each other.

4. The sheet processing machine according to any one of claims 1 to 3, wherein the processing station includes tools arranged at least partially in the detection areas (53, 78), and wherein the control unit (48) includes a storage module (50) for storing information about the tools.

5. The sheet processing machine according to claim 4, wherein information about the tool includes a light blocking diagram indicating whether the grating is interrupted by the tool.

6. The sheet processing machine of claim 5, wherein the light blocking diagram indicates whether one or more of the light rays are interrupted by a tool.

7. The sheet processing machine according to claim 4, wherein the information regarding the tool includes a tool identifier.

8. The sheet processing machine according to claim 7, wherein if the tool identifier is not already stored in the storage module (50) with an associated light blocking pattern, the control unit (48) is adapted to automatically determine the light blocking pattern of the tool.

9. The sheet processing machine according to claim 4, wherein the control unit (48) is adapted to enter a learning mode to obtain information about the tool.

10. The sheet processing machine according to claim 4, wherein the tool is a blanking tool (23).

11. The sheet processing machine according to claim 5, wherein the sheet processing machine includes a human-machine interface (52) connected to the control unit (48).

12. The sheet processing machine according to claim 11, wherein the control unit (48) is adapted to transmit a warning message to the human-machine interface (52) in the event that the grating is interrupted.

13. The sheet processing machine according to claim 12, wherein the control unit (48) transmits the warning information only if the interruption of the grating does not correspond to the light blocking pattern of the tool stored in the storage module (50).

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