Machine structure for feeding a sheet-like substrate having a first belt feeder and a second belt feeder, and a printing press having such a machine structure

Abstract

A machine structure for feeding a single sheet of paper-like substrate (01), comprising a first belt feeder (02) and a second belt feeder (03), wherein the belt feeders (02; 03) respectively have a conveyor belt (04; 06) rotating in an endless manner, and substrates (01) fed on the corresponding conveyor belts (04; 06) are arranged successively along a conveying direction (T). The substrate (01) to be transferred from the first belt feeder (02) to the second belt feeder (03) is lifted from the conveyor belt (04; 06) of the first belt feeder (02) by means of an air flow generated by a lifting nozzle (19) and an air flow generated by an opposing nozzle (19) in opposition thereto. The substrate (01) to be transferred is held stationary before it is transferred by means of a low pressure generated by a suction chamber (24) of the first belt feeder (02). The suction chamber (24) for fixing the substrate (01) is arranged closely at the lifting area (H). The present invention also relates to a printing machine having such a machine structure.

Description

Technical Field

[0001] The invention relates to a machine structure for feeding sheet-like substrates according to claim 1 and to a printing press having such a machine structure according to claim 11 . Background Art

[0002] EP 3025867 A1 discloses a sheet transport structure for transporting sheets of paper along a processing unit, wherein the processing unit is configured to process the sheets of paper, and the sheet transport structure comprises the following components:

[0003] a transport unit having a conveyor belt and a deflecting element, wherein the conveyor belt is designed to transport the individual sheets to the deflecting element in a transport direction along the processing unit, the individual sheets being deposited on the conveyor belt with a depositing side and with a processing side facing the processing unit, and the deflecting element being arranged in contact with the conveyor belt in order to deflect the conveyor belt downstream in the transport direction relative to the processing unit;

[0004] A separation unit for separating a sheet of paper from a conveyor belt, the separation unit being connected to an air supply source and comprising a retention blowing device, which is arranged in a holding area in order to direct a retention air flow towards a processing side of the sheet of paper so as to press the sheet of paper towards the conveyor belt in the vicinity of a deflection element, and a lifting blowing device, which is arranged in a lifting area in order to direct a lifting air flow towards a laying side of the sheet of paper so as to lift the sheet of paper from the conveyor belt, the lifting area being arranged in such a way that the lifting area extends only over a middle section of the width of the sheet of paper, the width being the dimension of the sheet of paper in a lateral direction perpendicular to the conveying direction.

[0005] A feeder is known from JP2013-040007A, which can perform the transfer of workpieces between feed units without friction, and includes a plurality of feed units, wherein a belt is tensioned to be placed between at least two rollers positioned separately from each other, and the belt is rotated by driving the rollers so that the workpieces located on the surface of the conveyor belt are sucked and fed while lying flat. The feeder includes: a scraper, which is arranged on the downstream side of the feed unit to scrape the workpieces from the surface of the belt; and an air jet section, which is arranged before the downstream roller of the conveyor unit, and is used to blow air from the back side of the belt to the lower surface of the workpiece.

[0006] JP2006036471A relates to a solution for preventing the front end and the rear end of a substrate conveyed in a bent state from a device on a supply side to a device on a receiving side from coming into contact with a counterpart device.

[0007] JPS55-135024A relates to a feeder in which air is injected toward a bridge portion of two conveyor belts, or a floating system for sucking material is provided to ensure safe conveyance without the material being caught between the conveyor belts.

[0008] DE 10 2019 208 156 A1 discloses a printing press comprising a first conveyor belt for conveying individual sheets of paper and a following second conveyor belt and guide elements for the individual sheets of paper in between, and a blowing device for lifting the leading edge of the respective individual sheets of paper in the region of the transition from the first conveyor belt to the guide element. The blowing device is preferably arranged in front of the guide element and in the orbit of the first conveyor belt, as viewed in the conveying direction of the individual sheets of paper, and the conveyor belt has perforations, for example, and the blowing device blows through the perforations onto the respective individual sheets of paper.

[0009] DE102021118468B3 discloses a machine structure having a plurality of processing stations for processing individual sheets of paper respectively, wherein the processing stations are arranged one after the other in a conveying direction of the individual sheets of paper, wherein at least one of the processing stations has a first conveying device for conveying the individual sheets of paper along a straight conveying section, the first conveying device having at least one conveyor belt that deflects on a deflection roller and rotates in an endless manner, wherein the first conveying device is designed to be able to convey a series of individual individual sheets of paper that follow each other while lying flat on at least one of its conveyor belts, and a second conveying device is arranged behind the processing station having the first conveying structure, which also conveys the individual sheets of paper flatly on at least one conveyor belt that rotates in an endless manner along the straight conveying section, and the individual sheets of paper to be conveyed are conveyed by the second conveying device. In the feeding plane of the sheets of paper, at the position where the single sheets of paper to be conveyed are transferred from the conveyor belt of the first conveying device to the conveyor belt of the second conveying device following in the conveying direction of the single sheets of paper, discontinuities are respectively constructed in the mechanical support part of the corresponding single sheets of paper to be transferred, and a deflection roller for deflecting at least one conveyor belt of the first conveying device is arranged at the discontinuity in the mechanical support part of the single sheets of paper to be transferred, and a guide device with a profile element with a sharp end extending transversely to the conveying direction of the single sheets of paper is arranged at the discontinuity, the tip of the profile element points to the conveyor belt of the first conveying device opposite to the conveying direction of the single sheets of paper, and at least one lifting nozzle is arranged in the profile element, and the relevant lifting nozzle is designed to be open in the direction of the tip of the profile element. Summary of the invention

[0010] The object of the present invention is to provide a machine structure for feeding sheet-like substrates and a printing press having such a machine structure, wherein, at high transport speeds of several thousand substrates per hour, for example 5,000 to 10,000 substrates per hour, and in the case of small-format substrates, i.e. in particular with a short side length of less than 300 mm in the transport direction of the substrates to be transported, an interference-free transfer of the substrates from a first belt feeder to a subsequent second belt feeder is ensured.

[0011] According to the invention, this object is achieved by the features of claims 1 and 11. The respective dependent claims relate to advantageous refinements and / or improvements of the solution found.

[0012] The advantages achievable by the invention are in particular that in a machine design for feeding individual paper-like substrates, at high transport speeds of several thousand substrates per hour, for example several thousand substrates per hour, for example 5000 to 10000 substrates per hour, and in small formats, i.e. in particular with a short side length of less than 300 mm in the transport direction of the substrates to be transported, these individual paper-like substrates can be transferred from a first belt feeder to a subsequent second belt feeder in an operationally reliable and thus trouble-free manner. Further advantages can be derived from the following explanation of the invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Exemplary embodiments of the invention are illustrated in the drawings and will be described in more detail below.

[0014] in:

[0015] Figure 1 A first partial view showing a machine structure having a first belt feeder and a second belt feeder, each for feeding a single sheet-like substrate;

[0016] Figure 2 Shown according to Figure 1 A partial view of a printing press showing the machine structure;

[0017] Figure 3 Show according to Figure 1 A second partial view of the machine structure to illustrate its working principle. DETAILED DESCRIPTION

[0018] Figure 1 A first partial view of a simplified machine structure for feeding individual paper-like substrates 01 is shown. The machine structure has a first belt feeder 02 and a second belt feeder 03, the two adjacently arranged belt feeders 02; 03 each having an endlessly rotating conveyor belt 04; 06, and the substrates 01 to be fed are arranged one behind the other in a conveying direction T and lie flat on the respective conveyor belt 04; 06.

[0019] Such a machine structure (such as Figure 2 01 by means of a lithographic printing unit 07, wherein the lithographic printing unit 07 is designed to be able to print the single sheet-like substrate 01, for example, by an inkjet printing method. Thus, the lithographic printing unit 07 has, for example, at least one, preferably a plurality of inkjet printing heads 23. The inkjet printing heads 23, which are controlled by a control unit 33, apply water-based ink to the relevant substrate 01 according to the printed image to be created.

[0020] Such a printing press used in an industrial printing process usually has a plurality of machine units one after the other in the transport direction T of the substrate 01. In this case, at least one of these machine units is designed as a printing unit 09, at least one other machine unit is designed as a dryer 11 or a cooling device 12, or the dryer 11 is first provided one after the other and then the cooling device 12 is provided one after the other. In particular, these aforementioned machine units, which are each preferably arranged in their own machine frame and are therefore each designed, for example, as independent modules, are connected to the machine structure according to the invention for feeding the individual paper-like substrates 01, because in particular these machine units use such a machine structure. Furthermore, in the aforementioned printing press, it can be provided that the first paper feeder 08 conveys the individual paper-like substrates 01 to be printed individually one after the other to the printing unit 09, wherein the printing unit 09 has the aforementioned plateless printing unit 07. In a preferred embodiment of the printing press, the printed substrate 01 is conveyed to a dryer 11, which is designed, for example, as a through-type dryer, in particular as a hot air dryer, and may also have an infrared radiation device in addition to the hot air dryer. Since the substrate 01 is at least partially heated to, for example, above 80° C. when it passes through the dryer 11, a cooling section with a cooling device 12 can be advantageously provided directly after the dryer 11, which cools the printed and dried substrate 01 again to, for example, a temperature below 30° C. The substrate 01 can then be handed over to a second paper pusher 13 or a push rod in order to convey these substrates 01, for example, to a coating device or a mechanical reprocessing device. The three above-mentioned machine units - printing unit 09, dryer 11 and cooling device 12 preferably convey the substrate 01 in a translational manner, in particular by means of a belt feeder 02; 03, so that the machine structure according to the present invention is designed for feeding a single paper-like substrate 01, for example, at a transfer point between the printing unit 09 and the dryer 11 and / or at a transfer point between the dryer 11 and the cooling device 12 and / or at a transfer point between the cooling device 12 and a second paper pushing device 13 or a push rod.

[0021] Now, in practice, it has been shown that: for example, the above-mentioned transfer section is prone to failure in the conveyance of the substrate 01, especially at a high conveyance speed of several thousand substrates 01 per hour, because the leading edge 14 of the substrate 01 in the conveyance direction T sometimes gets stuck too easily on or in the corresponding transfer section, resulting in an interruption in the operation of the entire machine structure and related production interruptions. Since it always takes some time to eliminate the operation interruptions caused in this way, this problem can lead to considerable economic losses, especially when it is set that the substrate 01 should be fed at a conveyance speed of several thousand substrates 01 per hour, such as 5000 to 10000 substrates 01 per hour, in an industrial process, because the entire production process is adjusted according to this conveyance speed and thus also the substrate output.

[0022] The substrate 01 to be fed by means of the machine structure according to the invention is preferably rectangular in design and is made of, for example, paper or cardboard or paperboard. The difference between paper, cardboard, and paperboard lies in their respective grammage in grams, i.e., the weight of such a substrate per square meter. The grammage of paper is between 30 g / m 2 and 150 g / m 2 , the grammage of cardboard is between 150 g / m 2 and 600 g / m 2 , and the grammage of paperboard is 600 g / m 2 or more. However, the substrate 01 to be fed can also be made of synthetic material and / or made of thin metal sheets and / or designed as a composite body composed of, for example, multiple layers, where these layers are formed of different materials.

[0023] As is known from Figure 1 and Figure 2 , the load section of the conveyor belt 04 of the first belt feeder 02 immediately adjacent to the front of the second belt feeder 03 and the load section of the conveyor belt 06 of the second belt feeder 03 are arranged in the same transfer plane that extends linearly along the conveyance direction T of the substrate 01. The part of the corresponding conveyor belts 04; 06 on which the substrate 01 to be conveyed is rested during its conveyance is called the load section. The conveyor belt 04 of the first belt feeder 02 is deflected by at least 90° relative to the transfer plane at its rear end in the conveyance direction T of the substrate 01, preferably on the rotatable deflection roller 16. The conveyor belt 06 of the second belt feeder 03 is also deflected by at least 90° relative to the transfer plane at its front end in the conveyance direction T of the substrate 01, on the deflection roller 17, which is arranged at a first distance A from the deflection roller 16 of the first belt feeder 02 and is also preferably rotatable, in the same direction as the conveyor belt 04 of the first belt feeder 02. The corresponding rotation directions of the respective deflection rollers 16; 17 and thus also the winding directions of the corresponding conveyor belts 04; 06 are in Figure 1In particular, the deflection roller 16 of the first belt feeder 02 is preferably designed as a belt feed roller driving the conveyor belt 04 of the first belt feeder 02 .

[0024] The conveying plane has a discontinuity in the mechanical support of the substrate 01 to be conveyed in the region between the deflection rollers 16 of the first belt feeder 02 and the deflection rollers 17 of the second belt feeder 03. In order to make the substrate 01 to be conveyed slide on the discontinuity, a guide device 18 for guiding the substrate 01 to be conveyed is arranged in the region of the discontinuity between the deflection rollers 16 of the first belt feeder 02 and the deflection rollers 17 of the second belt feeder 03, and the guide device has at least one lifting nozzle 19. The guide device 18 extends both in the conveying direction T of the substrate 01 and transversely to the conveying direction T of the substrate 01, and has a sharply terminated profile element 21 extending transversely to the conveying direction T of the substrate 01, preferably in the form of a scraper, and the at least one lifting nozzle 19 of the guide device 18 is arranged to be open at the tip 22 of the profile element 21. A plurality of lifting nozzles 19 are preferably arranged in at least one row in the tip 22 of the profile element 21 of the guide device 18. The tip 22 of the profile element 21 is directed at least approximately tangentially to the conveyor belt 04 of the first belt feeder 02, counter to the conveying direction T of the substrate 01, and is arranged spaced apart from the conveyor belt 04 deflected on the deflection roller 16 of the first belt feeder 02 by a first gap. The first gap has a gap width S in the range of, for example, 1 mm to 5 mm, wherein the gap width S is designed to be greater than the thickness d of the substrate 01.

[0025] At least the conveyor belt 04 of the first belt feeder 02 is designed as a flat suction belt with perforations in its conveying surface, and the substrate 01 to be conveyed is held in a force-locked manner with its placement surface lying flat on the perforated conveying surface of the suction belt. The force lock is achieved by a low pressure that applies a suction force, and the low pressure that holds the substrate 01 to be conveyed on the suction belt is a low pressure that forms the surrounding atmospheric pressure in relation to the machine structure, wherein the low pressure is generated by means of a suction device and is also adjusted in value, for example. The suction device that applies the suction force to the conveyor belt 04 of the first belt feeder 02, which is designed as a suction belt, has at least one suction chamber 24 below the load belt of the conveyor belt 04. The load section of the conveyor belt 04 designed as a suction belt is preferably supported by one or more support rollers 34 extending transversely to the conveying direction T of the substrate 01, at least in the region of the relevant suction chamber 24. However, the load section of the conveyor belt 06 of the second belt feeder 03 can also be supported at least partially by one or more support rollers 36 extending transversely to the conveying direction T of the substrate 01. This is advantageous if the conveyor belt 06 of the second belt feeder 03 is designed as a suction belt and at least one suction chamber is arranged below the load section of the conveyor belt 06. The support rollers 36 are then arranged in particular in the region of this suction chamber.

[0026] The wall 27 of the last suction chamber 26 of the suction device assigned to the first belt feeder 02 in the conveying direction T of the substrate 01 is arranged at a second spacing B with the deflection roller 16 of the first belt feeder 02 immediately before the deflection roller 16 in the conveying direction T of the substrate 01. The second spacing B is, for example, 1.5 mm to 3 mm. The wall 27 of the last suction chamber 26 of the suction device assigned to the first belt feeder 02 in the conveying direction T of the substrate 01 is arranged, for example, obliquely relative to a conveying plane extending straightly in the conveying direction T of the substrate 01, or it forms an equal spacing with the shell surface 28 of the deflection roller 16 of the first belt feeder 02 on an arc segment, for example. In this design, the wall 27 of the last suction chamber 26 in the conveying direction T of the substrate 01 is arranged obliquely, that is, arranged at an acute angle to the conveying plane extending straight in the conveying direction T of the substrate 01, which angle is open opposite to the conveying direction T of the substrate 01.

[0027] In a preferred embodiment, the last suction chamber 26 in the conveying direction T of the substrate 01 is loaded with a numerically greater low pressure than at least one suction chamber 24 located before the last suction chamber 26. The low pressure in the last suction chamber 26 in the conveying direction T of the substrate 01 is set to 6000 Pa, for example, while in at least one other suction chamber 24 arranged previously, the low pressure is set to 600 Pa, for example. Therefore, the low pressure in the last suction chamber 26 in the conveying direction T of the substrate 01 can, for example, be set to be ten times higher than that in at least one other suction chamber 24 arranged previously. In a preferred embodiment, the last suction chamber 26 in the conveying direction T of the substrate 01 extends along the conveying direction T of the substrate 01 over a length L26 of not more than 100 mm, while at least one other suction chamber 24 arranged previously can have a length of more than 1000 mm in the conveying direction T of the substrate 01. The wall 27 of the last suction chamber 26 in the transport direction T of the substrate 01 and the outer surface 28 of the deflection roller 16 of the first belt feeder 02 are arranged in such a way that a channel 29 is formed through which air can flow.

[0028] Furthermore, at least one opposing nozzle 31 is provided, and the relevant opposing nozzle 31 is arranged to be able to blow air in the direction of the suction belt into the channel 29 formed by the wall 27 of the last suction chamber 26 in the conveying direction T of the substrate 01 and the shell surface 28 of the deflection roller 16 of the first belt feeder 02. It is provided here that the air blown into the channel 29 escapes before the tangent point 32 formed by the suction belt on the deflection roller 16 of the first belt feeder 02 in the conveying direction T of the substrate 01, through the suction belt and pressed against the substrate 01 placed on the suction belt. The air outlet is preferably located directly before the tangent point 32 or at least at a third spacing C from the tangent point 32, and the third spacing C is smaller than the radius R of the relevant deflection roller 16 of the first belt feeder 02. The air flow escaping from one of the at least one lifting nozzles 19 of the guide device 18 and the air flow generated by the at least one opposing nozzle 31 in the channel 29 and passing through the suction belt are preferably directed toward each other in the front above the tangent point 32 of the deflection roller 16 of the first belt feeder 02. The two air flows form a combined air flow in the effective area W extending along the shell surface 28 of the deflection roller 16 above the tangent point 32 of the deflection roller 16 of the first belt feeder 02 and shorter than the diameter D of the deflection roller 16 of the first belt feeder 02. The combined air flow exerts a pressure acting toward at least a part of the placement surface of the substrate 01 between the suction belt and the substrate 01 to be conveyed thereon, whereby the combined air flow in particular lifts the front edge 14 of the substrate 01 to be conveyed away from the conveying surface of the conveyor belt of the first belt feeder 02, which is designed as a suction belt 04. During its further transport, the entire substrate 01 is finally lifted onto the guide 18 and thus passes over the discontinuity in the mechanical support and is transported in a running-reliable manner in the transport plane to the conveyor belt 06 of the second belt feeder 03 .

[0029] Figure 3 Now show that according to Figure 1 A second partial view of the machine structure of FIG. 2 is provided to illustrate its operating principle. The substrate 01 which is conveyed in the conveying direction T by the conveyor belt 04 of the first belt feeder 02 which is designed as a suction belt is first held on its support surface in a force-locking manner by the negative pressure generated by at least one suction chamber 24 and in the further course of conveying by the negative pressure generated by the last suction chamber 26, wherein the negative pressure generated by the last suction chamber 26 is held in a force-locking manner on the suction belt. Figure 3In the figure, it is indicated by two directional arrows and is adjusted, for example, to be ten times stronger than the low pressure generated by at least one suction chamber 24 arranged in front in the conveying direction T of the substrate 01. After the front edge 14 of the relevant substrate 01 has passed the action area determined by the length L26 of the last suction chamber 26 in the further conveying process along the conveying direction T, the front edge 14 of the relevant substrate 01 reaches the following action area W, in which the area W of the air flow generated by the at least one lifting nozzle 19 of the guide device 18 and the air flow generated by the at least one opposing nozzle 31 in the channel 29 and passing through the suction belt form a combined air flow. These two air flows (as in Figure 3 The two air flows are directed in opposite directions (indicated by directional arrows in the figure) and meet above the tangent point 32 of the deflection roller 16 of the first belt feeder 02. In the absence of other possible discharge solutions, the two air flows merge into a single air flow directed toward the placement surface of the conveyed substrate 01, which exerts pressure on the placement surface of the conveyed substrate 01. The pressure is first Figure 3 The application is shown towards the front edge 14 of the respective substrate 01. In the further course of transport, the entire placement surface of the transported substrate 01 is lifted off the suction belt of the first belt feeder 02 in this way. The spatial region in which the lifting occurs is referred to as the lifting region H, wherein the lifting region H is arranged within the action region W of the combined air flow.

[0030] The proposed solution makes it possible to securely hold the substrate 01 to be transported with its placement surface on the suction belt of the first belt feeder 02 on the one hand, and to guide the respective substrate 01 undisturbed through the discontinuity formed between the two belt feeders 02, 03 on the other hand. Since the negative pressure of the last suction chamber 26 is set to be stronger than the negative pressure of at least one suction chamber 24 arranged upstream, the substrate 01 to be transported is fixed until it reaches the lifting area H. Since the last suction chamber 26 of the first belt feeder 02 in the conveying direction T maintains the low pressure of the substrate 01 to be conveyed in a force-locking manner at a third distance C that is smaller than the radius of the relevant deflection roller 16 of the first belt feeder 02 and thus reaches the tangent point 32 of the deflection roller 16 of the first belt feeder 02 very closely, and the last suction chamber 26 also extends only over a length L26 that is shorter than the suction chamber 24 arranged previously, preferably less than 100 mm, the substrate 01 to be conveyed can be reliably fixed until a very short distance from the tangent point 32 of the deflection roller 16 of the first belt feeder 02, which is particularly advantageous for a substrate 01 having a relatively short length in the conveying direction T. By strengthening the combined air flow formed by the at least one lifting nozzle 19 of the guide device 18 and the air flow generated by the at least one counter nozzle 31 in the channel 29 and penetrating the suction belt in the lifting area H to such an extent that the bending moment that lifts the relevant substrate 01 off the suction belt is first applied to the front edge 14 of the substrate 01 being conveyed and fixed on the suction belt by the negative pressure of the last suction chamber 26, and then in the further conveying process, is applied to the entire placement surface of the substrate 01 to be conveyed. This reliably prevents the front edge 14 of the relevant conveyed substrate 01 from getting stuck at or in the discontinuity constructed between the two belt feeders 02; 03, that is, getting stuck at the relevant transfer point, so that operating failures and accompanying production interruptions due to the entire machine structure being stuck can be reliably avoided.

[0031] The solution found therefore has the following advantages: it transports the substrates 01 at a high transport speed of several thousand substrates 01 per hour, for example in the range of between 5,000 and 10,000 substrates 01 per hour, and in the case of very short substrate formats with a side length along the transport direction T, for example less than 300 mm, the handover from the first belt feeder 02 to the second belt feeder 03 arranged downstream can operate reliably and therefore without failure.

[0032] Reference numerals list

[0033] 01Base material

[0034] 02The first belt feeder

[0035] 03The second belt feeder

[0036] 04Conveyor Belt

[0037] 05-

[0038] 06Conveyor Belt

[0039] 07Printless printing device

[0040] 08The first paper pusher

[0041] 09Printing Unit

[0042] 10–

[0043] 11Dryer

[0044] 12 Cooling device

[0045] 13 Second paper pushing device

[0046] 14 front edge

[0047] 15–

[0048] 16 Deflection roller

[0049] 17 Deflection roller

[0050] 18 Guidance Device

[0051] 19 Lift your mouth

[0052] 20–

[0053] 21 Profile elements

[0054] 22 Tip

[0055] 23Inkjet Print Head

[0056] 24 Suction chambers

[0057] 25–

[0058] 26 Final suction chamber

[0059] 27 Wall

[0060] 28 Shell

[0061] 29 channels

[0062] 30–

[0063] 31 Opposing Mouth

[0064] 32 Tangent Points

[0065] 33Control Unit

[0066] 34 Support rollers

[0067] 35–

[0068] 36 support rollers

[0069] A Spacing

[0070] B spacing

[0071] C spacing

[0072] D diameter

[0073] dThickness

[0074] H lifting area

[0075] L26 length

[0076] R Radius

[0077] S Gap Width

[0078] TTransmission direction

[0079] W Area of ​​Effect

Claims

1. A machine structure for feeding a substrate (01) in the form of a single sheet of paper, the machine structure comprising a first belt feeder (02) and a second belt feeder (03), wherein: The belt feeders (02; 03) respectively have endlessly rotating conveyor belts (04; 06) and are arranged one behind the other along the conveying direction (T) of the substrate (01) conveyed on the corresponding conveyor belts (04; 06), wherein the conveyor belt (04) of the first belt feeder (02) and the conveyor belt (06) of the second belt feeder (03) are arranged in the same conveying plane extending in a straight line along the conveying direction (T) of the substrate (01), wherein the conveyor belt (04) of the first belt feeder (02) is deflected at least 90° relative to the conveying plane on a deflection roller (16) at its rear end along the conveying direction (T) of the substrate (01), and the conveyor belt (06) of the second belt feeder (03) is deflected at least 90° relative to the conveying plane at its front end along the conveying direction (T) of the substrate (01). The conveying plane is deflected at least 90 degrees in the same direction as the conveyor belt (04) of the first belt feeder (02) at the end thereof on a deflection roller (17) arranged at a first distance (A) from the deflection roller (16) of the first belt feeder (02), wherein the conveying plane has a discontinuity in the mechanical support of the substrate (01) to be conveyed in the region between the deflection roller (16) of the first belt feeder (02) and the deflection roller (17) of the second belt feeder (03), wherein the deflection roller (16) of the first belt feeder (02) and the deflection roller (17) of the second belt feeder (03) are arranged at a first distance (A) from the deflection roller (16) of the first belt feeder (02) and the deflection roller (17) of the second belt feeder (03). 17), a guide device (18) is arranged in the region of a discontinuity between the substrate (01) and the substrate (01) to be conveyed, the guide device having at least one lifting nozzle (19), wherein the guide device (18) has a sharply terminated profile element (21) extending transversely to the conveying direction (T) of the substrate (01), wherein the at least one lifting nozzle (19) of the guide device (18) is arranged to lead to a tip (22) of the profile element (21), wherein the tip (22) of the profile element (21) is opposite to the conveying direction (T) of the substrate (01). ) is directed toward a conveyor belt (04) of a first belt feeder (02) and is spaced apart from the conveyor belt (04) deflected on a deflection roller (16) of the first belt feeder (02) by a first gap, wherein at least the conveyor belt (04) of the first belt feeder (02) is designed as a suction belt for retaining a corresponding substrate (01) placed on its placement surface in a force-locking manner, wherein the suction force is achieved by a low pressure generated by a suction device in relation to the surrounding atmospheric pressure, wherein the suction device for achieving the suction force on the suction belt of the first belt feeder (02) has at least one suction chamber (24), whereinThe wall (27) of the last suction chamber (26) of the suction device in the conveying direction (T) of the substrate (01) is arranged at a second distance (B) from the deflection roller (16) of the first belt feeder (02) in the conveying direction (T) of the substrate (01) immediately before the deflection roller (16), wherein the wall (27) of the last suction chamber (26) in the conveying direction (T) of the substrate (01) and the shell surface (28) of the deflection roller (16) of the first belt feeder (02) are The invention relates to a method for forming a channel (29) through which air can flow, wherein at least one opposing nozzle (31) is provided, and the corresponding opposing nozzle (31) is arranged in such a way that air can be blown toward the suction belt into the channel (29) formed by the wall (27) of the last suction chamber (26) in the conveying direction (T) of the substrate (01) and the shell surface (28) of the deflection roller (16) of the first belt feeder (02), wherein the method is configured to: blow air into the channel (29) The air escapes in the conveying direction (T) of the substrate (01), through the suction belt at the tangent point (32) formed by the suction belt on the deflection roller (16) of the first belt feeder (02), and is pressed against the substrate (01) placed on the suction belt, wherein the air flow coming out of the at least one lifting nozzle (19) of the guide device (18) and the air flow generated by the at least one opposing nozzle (31) in the channel (29) and coming out through the suction belt at the first belt feeder (02) are The two air flows are directed toward each other above a tangent point (32) of a deflection roller (16) of a first belt feeder (02), wherein the two air flows form a combined air flow in an effective area (W) extending shorter than the diameter (D) of the deflection roller (16) of the first belt feeder (02), wherein the combined air flow is directed in such a way that the combined air flow exerts a pressure force acting toward at least a part of the placement surface of the substrate (01) between the suction belt and the substrate (01) to be conveyed on the suction belt.

2. The machine structure according to claim 1, characterized in that: The deflection roller (16) of the first belt feeder (02) is designed as a belt feed roller for driving the conveyor belt (04) of the first belt feeder (02).

3. The machine structure according to claim 1 or 2, characterized in that: The load section of the conveyor belt (04) of the first belt feeder (02) designed as a suction belt is supported by one or more support rollers (34) extending transversely to the conveying direction (T) of the substrate (01), at least in the area of ​​a suction chamber (24) that realizes the suction force on the suction belt.

4. The machine structure according to claim 1, 2 or 3, characterized in that: A first gap between a tip (22) of a profile element (21) of the guide device (18) and a conveyor belt (04) deflected on a deflection roller (16) of a first belt feeder (02) has a gap width (S) in the range of 1 mm to 5 mm.

5. The machine structure according to claim 1 or 2 or 3 or 4, characterized in that: The tip (22) of the profile element (21) of the guide device (18) is oriented tangentially relative to the conveyor belt (04) of the first belt feeder (02).

6. The machine structure according to claim 1 or 2 or 3 or 4 or 5, characterized in that: The last suction chamber (26) in the transport direction (T) of the substrate (01) is subjected to a greater vacuum than at least one suction chamber (24) arranged upstream of the last suction chamber (26).

7. The machine structure according to claim 1 or 2 or 3 or 4 or 5 or 6, characterized in that: The last suction chamber (26) in the transport direction (T) of the substrate (01) is shorter than at least one suction chamber (24) arranged upstream of the last suction chamber (26) in the transport direction (T) of the substrate (01).

8. The machine structure according to claim 1 or 2 or 3 or 4 or 5 or 6 or 7, characterized in that: The last suction chamber ( 26 ) in the transport direction (T) of the substrate ( 01 ) has a length ( L26 ) of no more than 100 mm in the transport direction (T) of the substrate ( 01 ).

9. The machine structure according to claim 1 or 2 or 3 or 4 or 5 or 6 or 7 or 8, characterized in that: The wall (27) of the last suction chamber (26) of the suction device associated with the first belt feeder (02) in the conveying direction (T) of the substrate (01) is arranged to be inclined relative to a conveying plane extending along a straight line in the conveying direction (T) of the substrate (01), and / or to form an equidistant distance from the shell surface (28) of the deflection roller (16) of the first belt feeder (02) on an arc segment.

10. The machine structure according to claim 1 or 2 or 3 or 4 or 5 or 6 or 7 or 8 or 9, characterized in that: The combined air flow exerts pressure on at least a portion of the placement surface of the substrate (01) between the suction belt of the first belt feeder (02) and the substrate (01) to be conveyed thereon to form a lifting area (H) in the space region, wherein the lifting area (H) is arranged within the action area (W) of the combined air flow.

11. A printing machine having a machine structure according to claim 1 or 2 or 3 or 4 or 5 or 6 or 7 or 8 or 9 or 10, wherein: A plurality of machine units are arranged one behind the other in a transport direction (T) of a substrate (01), wherein at least one of the machine units is designed as a printing unit (09) and at least one other machine unit is designed as a dryer (11) or a cooling device (12), wherein the machine units designed as printing units (09) or as dryers (11) or as cooling devices (12) are each arranged in a separate machine frame, wherein each of the machine units is designed to be able to transfer the substrate to the substrate by means of a belt feeder (02; 03) to transport the substrate (01), wherein at the transfer point between the printing unit (09) and the dryer (11) and / or at the transfer point between the dryer (11) and the cooling device (12) and / or at the transfer point between the cooling device (12) and a paper pushing device (13) arranged after the cooling device, a discontinuity in the mechanical support part of the substrate (01) to be transported is constructed between the corresponding first belt feeder (02) and the corresponding second belt feeder (03).

12. The printing press according to claim 11, characterized in that The printing unit (09) has a non-printing printing device (07) for printing a substrate (01) using an inkjet printing method, wherein each of the non-printing printing devices (07) has at least one inkjet printing head (23) controlled by a control unit (33).

13. The printing press according to claim 11 or 12, characterized in that: The dryer (11) is designed as a through-flow dryer, and the dryer (11) is designed as a hot air dryer.

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