Method for conveying a tray to a graphic industry machine having a sheet feeder

Abstract

The invention relates to a method for delivering a tray (7) to a graphic industry machine (1) having a sheet feeder (3), characterized by the following steps: positioning the tray (7) in a waiting position (13) of a delivery device (4) for the tray (7); a first release (21) of the movement of the tray (7) and moving the tray (7) out of the waiting position (13); a second release (24) of the further movement of the tray (7) and further moving (26) the tray (7) into the sheet feeder (3). The invention enables in an advantageous manner to speed up the process of stack change.

Description

Technical Field

[0001] The present invention relates to a method for conveying a pallet to and within a graphic industrial machine having a sheet feeder.

[0002] This invention is in the field of graphic industry technology, and particularly in the field of conveying a tray having a stack of sheets of printing material to a feeder and thereby changing the stack in the feeder, especially in so-called ANS (“Auto-Non-Stop”) operation. Background Technology

[0003] DE 27 14 612 A1 discloses a device for automatically changing stacks at the paper receiver of a printing press.

[0004] DE 40 23 877 A1 discloses a machine for processing sheets and a conveying device for stacking sheets that works in conjunction with it. Here, the loaded pallets move.

[0005] DE 101 22 430A1 discloses a buffer station for logistics in a printing plant. The disclosed features a conveyor section and a stopping station for loaded pallets.

[0006] No documents disclose the release or how it is carried out. Summary of the Invention

[0007] Therefore, the object of the present invention is to propose an improved solution relative to the prior art, which in particular enables the stacking changeover process and thereby accelerates machine productivity.

[0008] The task is solved by the method of a preferred embodiment of the present invention.

[0009] Advantageous and therefore preferred extensions of the invention are derived from alternative embodiments, as well as the description and drawings.

[0010] The present invention relates to a method for conveying a pallet to a graphic industrial machine having a sheet feeder, characterized by the following steps: positioning the pallet in a waiting position of a pallet conveying device; a first release, i.e., releasing the movement of the pallet and moving the pallet out of the waiting position; a second release, i.e., releasing further movement of the pallet and moving the pallet further into the sheet feeder.

[0011] Advantageous extensions and effects of the present invention

[0012] This invention advantageously enables the acceleration of the stack changeover process. According to the invention, this is achieved by dividing the release process for moving the loaded pallet from the waiting position into the sheet feeder into two parts, and thereby advantageously designing it.

[0013] The first release advantageously allows the tray to move toward the sheet feeder. For this purpose, the tray can preferably accelerate from a standstill to a defined (i.e., predetermined) speed, for example, to a defined maximum speed, outside the sheet feeder. The second release advantageously allows the tray to move further into the sheet feeder. For this purpose, the tray is preferably able to move further into the sheet feeder at the defined speed and can move further within the sheet feeder. In this way, the tray can be pre-accelerated, i.e., moved into the sheet feeder at a higher speed than in the prior art. Furthermore, the two-part release process advantageously allows for an automatic emergency stop after the first release and before the second release in case of problems.

[0014] Overall, this invention advantageously improves machine productivity through faster stack changeovers. Model calculations show that 3 to 5 seconds can be gained for each stack changeover, thereby allowing for the additional printing of more than 2,500,000 pages per year.

[0015] Extended solutions of the present invention

[0016] Preferred extensions of the present invention (hereinafter referred to as "extensions") are described below.

[0017] One feature of this extended solution is the generation of a first signal for the initial release. This first signal can be generated, for example, before the safety device, such as a roller shutter or light curtain, is deactivated. This allows valuable production time to be gained. In the event of a problem, an emergency stop can always be automatically initiated.

[0018] One extension scheme is characterized by generating a second signal for the second release.

[0019] These two signals can be generated by the digital computer of the machine and / or the control unit of the conveyor. These signals can be transmitted to the drive of the conveyor and activate the drive.

[0020] One feature of the extended scheme is that the second release is performed in time such that an emergency stop of the tray can be made spatially before the sheet feeder, preferably before its sidewall, or temporally before reaching the sheet feeder.

[0021] One extension may feature that the conveying device includes a (horizontal) acceleration section for the pallet between the waiting position and the sheet feeder, preferably its sidewall.

[0022] One extension may be characterized in that the tray is accelerated as it moves out of the waiting position.

[0023] One feature of the extended scheme is that the tray is (positively) accelerated to a maximum speed. By selecting a sufficiently large acceleration section, the acceleration of the tray and the stacks formed on the tray by printing materials such as sensitive paper is carried out gently, thereby advantageously avoiding damage to the stacks or interference with the stack transport.

[0024] One feature of the extended scheme is that the tray enters the sheet feeder substantially at the maximum speed (preferably horizontally).

[0025] Another feature of this extended solution is that the maximum speed is predefined by a characteristic curve. This characteristic curve can be stored digitally in a digital computer.

[0026] Another extension may be characterized in that the characteristic curve is related to the weight and / or specifications and / or material and / or surface properties (e.g., smoothness or roughness) of the sheets on the tray or the stack of sheets formed by the sheets.

[0027] Another feature of this extended solution is that the tray moves continuously or without a stationary state between the first release and the second release.

[0028] Another extended solution is characterized in that the further movement of the tray is directly and continuously connected to the movement of the tray, without stopping or being in a static state.

[0029] Another extended embodiment is characterized in that the tray is braked (i.e., negatively accelerated) after it moves into the sheet feeder and stops or remains stationary in the sheet feeder, preferably between the two side walls of the sheet feeder.

[0030] Another extended solution is characterized in that the further movement of the tray into the sheet feeder is carried out through the opening of the sheet feeder, preferably the opening of the side wall of the sheet feeder.

[0031] Another extended solution may feature that the safety device for configuring the sheet feeder to the opening is deactivated before the tray moves further into the sheet feeder, or that the further movement of the tray into the sheet feeder is performed only after or during the deactivation of the safety device for configuring the sheet feeder to the opening.

[0032] Another extension may feature that the safety device includes a roller shutter that opens when deactivated.

[0033] Another extended solution may feature that the security device includes a grating and that the grating is turned off when deactivated.

[0034] Another extension may feature that the pallet is loaded with stacks of sheets, such as those made of paper, cardboard, or foil.

[0035] Another extended solution is characterized in that the loaded tray moves from one side into the sheet feeder and essentially simultaneously the empty tray moves out of the sheet feeder from the other side.

[0036] Another extension could be that the graphic industrial machine is a sheet printing press or a die-cutting machine.

[0037] Another extended solution is characterized in that the conveying device includes multiple conveying elements for correspondingly accommodating pallets.

[0038] The features and combinations of features disclosed in the above paragraphs on the technical field, the invention content and extensions, as well as in the following paragraphs on embodiments, constitute other advantageous extensions of the invention. Attached Figure Description

[0039] Figure 1 and Figure 2 Preferred embodiments of the invention and its extensions are illustrated. Corresponding features are indicated by the same reference numerals in the drawings. For clarity, some repeated reference numerals in the drawings are omitted.

[0040] Figure 1 The apparatus for implementing the preferred embodiment of the method of the present invention is shown at the top and a diagram is shown below.

[0041] Figure 2 A flowchart illustrating a preferred embodiment of the method of the present invention is shown. Detailed Implementation

[0042] exist Figure 1 The image shows a graphic industrial machine 1, which has two side walls 1a and 1b. The machine is situated on the ground 2, such as the floor of a printing plant, and is a sheet-fed printing press, such as an offset printing press. During printing, the individual sheets within the machine are transported perpendicular to the plane of the drawing. A sheet feeder 3 for machine 1 is also shown.

[0043] exist Figure 1The diagram also shows a conveying device 4 (a movable cart or rotatable roller) with a movable conveying element 5. The conveying element is preferably used for conveying in direction 6 and preferably transversely to the side wall 1a. Single pallets 7 are conveyed, loaded with stacks of sheets 8, or empty pallets 9 can also be conveyed. A controllable drive is preferably provided for this conveying. Control, particularly the conveying speed, is preferably performed by means of a digital computer 30 of the control unit.

[0044] The side wall 1a has an opening 10 through which the loaded tray 7 can move into the paper feeder 3. A safety device 11, such as a roller shutter 11a or a light curtain 11b, can be installed at the opening.

[0045] also, Figure 1 Multiple sensors 12 are shown at different locations along the conveyor 4: a first sensor 12a, a second sensor 12b, and a third sensor 12c. These sensors are used to detect trays 7 that are at or passing by the sensor monitoring points. The sensor signals are preferably transmitted to the digital computer 30.

[0046] also, Figure 1 A waiting position 13 for at least one tray 7 is shown, which is preferably located to the side of and spaced apart from the machine 1. Figure 1 In the loading position, the loaded pallet 7 is in waiting position 13. Between waiting position 13 and side wall 1a are a (longer) acceleration section 14 and a (shorter) emergency stop section 15. The acceleration section is preferably longer than the length of pallet 7, and the emergency stop section is preferably shorter than the length of pallet 7. The acceleration section may, for example, be greater than five or ten times the length of the emergency stop section. These two sections preferably transition directly into each other. Positive acceleration of the pallet preferably occurs entirely within the region of the acceleration section. Emergency stop (negative acceleration) of the pallet preferably occurs entirely within the region of the emergency stop section.

[0047] The tray 7 (especially an empty tray) can be removed from the paper feeder 3 through the side wall 1b and preferably by means of the conveyor 4.

[0048] According to the illustrated embodiments, the method of the present invention can be carried out as follows (see also...). Figure 2 ):

[0049] The loaded pallet 7 (preferably by means of a conveyor 4) is positioned in waiting position 13 (position 20), preferably in a stationary state. The first sensor 12a detects the presence of the pallet 7 and sends a corresponding signal to the digital computer 30 of the control device.

[0050] If a new stack of sheets 8 is needed in the sheet feeder 3, a first release 21 is preferably performed by generating a first signal 22 and preferably by a digital computer 30. Due to this release, the loaded tray 7 moves from the waiting position 13 toward the side wall 1a, a movement 23 of exiting the waiting position. Here, the loaded tray 7 accelerates, resulting in an increase in speed 16. The tray then reaches its maximum speed 17. This maximum speed can be predetermined and, for example, stored in the digital computer.

[0051] The second sensor 12b detects the tray 7 present (and after movement) at the (preferably direct) transition from the acceleration phase 14 to the emergency stop phase 15.

[0052] Now, assuming no problems arise (see later paragraphs for details), the second release 24 is preferably performed via the generation of the second signal 25 and preferably via the digital computer 30. Due to this release, the loaded tray 7 undergoes further movement 26 through the opening 10 into the sheet feeder 3. Here, the maximum speed 17 is initially maintained substantially.

[0053] However, if a predetermined problem exists, an emergency stop can be triggered by the digital computer 30. For this purpose, braking 27 (negative acceleration) is applied to the loaded tray 7 until it comes to a stop. This stop is achieved before the side wall 1a, i.e., outside the machine 1. The determined problem could be, for example, that the opening 10 is not free, for example because the shutter 11a is not yet open or not fully open, or because the grating 11b has not been deactivated; or that the tray 7 is still present in the sheet feeder and must be removed.

[0054] However, if no problems arise, the tray 7 moves further at maximum speed into the sheet feeder, that is, into the machine and within it. There, the third sensor 12c detects the arrival of the tray and sends a corresponding signal to the digital computer 30. The digital computer then initiates braking (negative acceleration) of the loaded tray 7 until it comes to a standstill 28. Here, the tray stops or remains stationary between the two side walls 1a and 1b in the sheet feeder 3. The tray, and thus the sheet stack, is now essentially in a horizontal position from which processing, such as printing, can be performed on the printing press. A slight, horizontal correction movement may be required before this processing.

[0055] Figure 1The prior art speed 19 is also shown. Here, the loaded tray 7 accelerates from a waiting position near the side wall 1a. Compared to the present invention, the acceleration phase is arguably within the sheet feeder, rather than laterally outside the sheet feeder. The loaded tray 7 does not move into the feeder 3 at maximum speed, but rather very slowly at first. Therefore, the movement duration of the loaded tray 7 is disadvantageously longer and the productivity is lower.

[0056] List of reference numerals

[0057] 1. Graphic Industrial Machine

[0058] 1a Sidewall

[0059] 1b Sidewall

[0060] 2 pages

[0061] 3-sheet paper feeder

[0062] 4 Conveying device

[0063] 5. Conveying elements

[0064] 6 directions

[0065] 7 trays

[0066] 8 pages stacked

[0067] 9 empty pallets

[0068] 10 Openings

[0069] 11 Safety devices

[0070] 11a Roller Shutter

[0071] 11b grating

[0072] 12 sensors

[0073] 12a First Sensor

[0074] 12b Second Sensor

[0075] 12c Third Sensor

[0076] 13 Waiting positions

[0077] 14 Acceleration Section

[0078] 15 Emergency Stop Section

[0079] 16. Speed ​​increases

[0080] 17 Maximum speed

[0081] 18. Speed ​​decreases

[0082] 19. Speed ​​in the prior art

[0083] 20. Positioning in the waiting area.

[0084] 21 First Release

[0085] 22 Generation of the first signal

[0086] 23 Movements emerging from the waiting position

[0087] 24 Second Release

[0088] 25 Generation of the second signal

[0089] 26. Further movement into the sheet feeder

[0090] 27 Braking

[0091] 28. Stillness

[0092] 29 Emergency Stop

[0093] 30. Digital computers.

Claims

1. A method for conveying a tray (7) to a graphic industrial machine (1) having a sheet feeder (3), Its characteristics include the following steps: Position the pallet (7) in a waiting position (13) of the conveying device (4) for the pallet (7), which is located to the side of the machine (1) and spaced apart from the machine (1); A first signal is generated for the first release to perform the first release, i.e., to release the movement of the tray (7) and to move the tray (7) out of the waiting position (13), wherein the tray (7) is accelerated to a defined speed when it moves out of the waiting position (13); After the tray (7) is accelerated to a defined speed and before the tray (7) enters the sheet feeder (3), a predetermined problem is detected; If there is no predetermined problem, a second signal is generated for the second release to perform the second release, that is, to release the further movement of the tray (7) and to move the tray (7) further into the sheet feeder (3) at the defined speed; If a predetermined problem exists, an emergency stop of the tray (7) is triggered.

2. The method according to claim 1, characterized in that, The second release is carried out in such a time that an emergency stop of the tray (7) is possible before the sheet feeder (3).

3. The method according to claim 1 or 2, characterized in that, The conveying device (4) includes an acceleration section (14) for the tray (7) between the waiting position (13) and the sheet feeder (3).

4. The method according to claim 1 or 2, characterized in that, The tray (7) is accelerated to the maximum speed (17).

5. The method according to claim 4, characterized in that, The tray (7) enters the sheet feeder at the maximum speed (17).

6. The method according to claim 5, characterized in that, The maximum speed (17) is pre-defined by the characteristic curve.

7. The method according to claim 1 or 2, characterized in that, The tray (7) does not move in a stationary state between the first release and the second release.

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