Corrugated forming and die cutting system and operation method thereof

Abstract

The invention discloses an integrated corrugated forming machine and a die cutting system. The system comprises: (a) a corrugating forming machine configured to produce an elongated and multi-ply moving corrugated board strip; (b) and a die cutter configured to receive the corrugated board strip and repeatedly cut it into a plurality of shaped boards.

Description

Technical Field

[0001] The present invention relates generally to the field of paper industry, and in particular to the production of corrugated board, such as for packaging. More specifically, the present invention relates to an integrated system combining fluting and die cutting in a single system, wherein the die cutting machinery receives a multi-layer paperboard strip from an improved corrugator. Background Art

[0002] Containerboard production (also referred to in this article as corrugated board) is the highest of all paper types worldwide. More than 100 million tons of corrugated board are produced each year.

[0003] Corrugated board is manufactured by large, high-precision mechanical production lines called corrugators, which typically run at about 500 feet per minute (150 m / min), usually 50-400 m / min. A corrugator consists of a group of machines that combine two, three, five or seven sheets of paper in a continuous process to temporarily form (within the corrugator) a strip of integrated board, which is then cut into separate (usually square or rectangular) multiple boards. The term "strip" refers to an essentially flat and "elongated" object. "Elongated" means that the strip is even as long as the paper wound on the feed reel of the corrugator.

[0004] In its most conventional 3-ply form, a corrugator employs at least five key stages: (a) corrugating the liner to form the flutes (the flutes are the corrugated middle layer of the final product); (b) gluing the flutes to the first layer of flat paper to form a joined liner; and (c) gluing another flat paper liner to the other side of the flutes in the previously joined liner, thereby forming an integral and rigid strip of corrugated board; (d) heating the strip to dry the glue; and (e) cutting the strip into separate rectangular panels using a set of longitudinal and transverse blades.

[0005] In more complex forms with five or seven layers, steps (b) and (c) of the above stage are repeated to receive a final different rectangular plate with five or seven layers.

[0006] The main material in the corrugating process is paper, and different grades of paper are sometimes used to make up each layer of the final product. Due to supply chain and scale considerations, paper is usually produced in separate factories (paper mills) and supplied to the corrugator in rolls. Several supply reels (one for each layer) are positioned at the entrance of the corrugator. In an attempt to increase production volume and reliability, corrugators have become very complex and expensive machines.

[0007] As mentioned above, all corrugators traditionally output a plurality of different corrugated boards. The different boards are then fed separately to a die-cutter to produce the final product, i.e., a corrugated board specifically configured in shape and size for a particular packaging product (or for another use). The die-cutter is sometimes located in the same production facility (as the corrugator) or at a separate facility (operated by the same or another entity relative to the operator of the corrugator).

[0008] Die cutters typically utilize various forms of templates, such as flatbed or rotary press. In any case, die cutters for processing corrugated board are designed to (a) receive different rectangular (or another contour) boards; and (b) cut, shape and / or warp each board to form a final product specially designed in shape and size for a specific purpose. Once different corrugated board sheets are received at the input, the die cutter can be configured to produce, for example, pizza boxes, boxes for packaging electrical appliances, boxes for containing fruit, or any other packaging (or other) products. In any case, all die cutters for processing and forming corrugated board receive different boards at their inlets and are configured to output boards that are shaped and cut to a certain size, and optionally suitable for easy folding into 3D boxes by the end user.

[0009] Each corrugator and die-cutter requires a separate operator, typically requiring 5 to 10 workers at any given time for each such machine. In addition, when these machines are located in different facilities, additional vehicles and workers are required for transportation. In addition, the die-cutter is forced to receive paperboard of the size produced by the corrugator, resulting in a significant loss of material in the die-cutter's final product.

[0010] The object of the present invention is to provide a system for simplifying the manufacture of products made of corrugated cardboard.

[0011] Another object of the present invention is to provide a system that allows for significant savings in paper material in the manufacture of products made of corrugated board.

[0012] Another object of the present invention is to provide a system that reduces the labor involved in producing products made from corrugated paperboard.

[0013] Another object of the present invention is to provide a system which significantly increases the throughput of a continuously operating corrugator and die cutter.

[0014] Other objects and advantages will become apparent as the description proceeds. Summary of the invention

[0015] The present invention relates to an integrated corrugator and die-cutting system, comprising: (a) a corrugator configured to produce an elongated and multi-layered moving strip of corrugated paperboard; and (b) a die-cutter configured to receive the strip of corrugated paperboard and repeatedly cut it into a plurality of formed panels.

[0016] In one embodiment of the present invention, the transverse blades and the longitudinal blades are eliminated in the corrugator.

[0017] In an embodiment of the invention, the elongated multi-layer strip comprises 2, 3, 5 or 7 layers.

[0018] In an embodiment of the invention, the strip comprises printing, and wherein the printing is selected from pre-printed, printed in the corrugator or printed in or after the die-cutter.

[0019] In one embodiment of the invention, the corrugator comprises a built-in printing press selected from a flexographic printing press, an offset printing press, a rotary printing press or a digital printing press.

[0020] In one embodiment of the invention, a separate glue drying unit of the corrugator is positioned above the main body of the corrugator.

[0021] The system of claim 1 further comprising synchronization between a speed of movement of the strip at an exit of the corrugator and an operating speed of the die cutter.

[0022] In an embodiment of the present invention, the synchronization is performed at a region between the corrugating machine and the die-cutter by means of a synchronization unit external to the corrugating machine and the die-cutter.

[0023] In an embodiment of the present invention, the system includes two die cutters operating alternately.

[0024] In an embodiment of the present invention, the synchronization unit includes: (a) the strip forms a ground curve of a predetermined height h; (b) a laser unit that continuously measures the height h and feeds the height to the synchronization entity; and (c) the synchronization entity is configured to receive the height h and adjust the operating speed of one or more of the corrugating machine or the die-cutter to keep the height h constant.

[0025] In an embodiment of the present invention, synchronization is achieved by a die-cutter comprising: (a) an upper base and a lower base, wherein the upper base comprises a flat plate template facing downward and the lower base comprises a flat surface facing upward toward the template; (b) a mechanism configured to apply a rotational circular or elliptical motion to each of the upper base and the lower base so that when engaged, the two bases are horizontal relative to the corrugated strip passing between them; and (c) a synchronization unit configured to synchronize between the horizontal movement vectors of the two bases and the speed of the strip moving between them at each engagement time.

[0026] In an embodiment of the present invention, the mechanism includes (a) a drive element at each of the upper base and the lower base; (b) an axis attached to the drive element; and (c) a motor configured to apply rotation in an opposite direction to the axis driving the upper base relative to the axis driving the lower base.

[0027] In an embodiment of the present invention, the system further comprises a feeding auxiliary device located at the inlet of the die-cutting machine.

[0028] In an embodiment of the present invention, the die cutter is selected from a rotary or flat-bed die cutter.

[0029] In one embodiment of the present invention, the system further comprises a static or dynamic conveyor between the corrugator and the die cutter, which is configured to assist in the movement of the strip.

[0030] The present invention also relates to a method for producing formed corrugated paperboard, comprising: (a) providing a corrugator configured to produce elongated multi-layer corrugated strips; and providing a die-cutter configured to continuously receive the multi-layer corrugated strips and cut the strips into a plurality of separate formed boards.

[0031] In one embodiment of the invention, the method further comprises printing the strips before the corrugator, in the corrugator or in the die-cutter, or printing separate multiple formed boards outside the die-cutter.

[0032] In one embodiment of the present invention, the method further comprises synchronizing the operating speed of the corrugator and the operating speed of the die-cutter.

[0033] In an embodiment of the present invention, the method also includes: (a) providing a second die-cutter, and at any given time, at most one of the die-cutter is in operation and the other is inoperative; (b) when a new job needs to be changed, a new template is installed in the inoperative die-cutter and the inoperative die-cutter is fine-tuned; and (c) starting operation with the newly adjusted die-cutter. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] FIG1 shows the overall structure of a prior art corrugated paperboard;

[0035] FIG2 shows the overall structure of a prior art corrugated forming machine;

[0036] Figure 3 The overall structure of the improved corrugated forming machine according to the embodiment of the present invention is shown;

[0037] Figure 4a The overall structure of an integrated corrugating machine and die-cutting system according to one embodiment of the present invention is shown;

[0038] Figure 4b shows a similar Figure 4a The system of systems, however, has two die cutters working alternately;

[0039] Figure 5 The overall structure of an integrated corrugating machine and die-cutting system according to one embodiment of the present invention is shown;

[0040] Figure 6 The overall structure of an improved corrugated forming machine according to one embodiment of the present invention is shown, and the corrugated forming machine includes a built-in printing machine;

[0041] Figure 7a The overall structure of a unified corrugating machine and die-cutting system according to an additional embodiment of the present invention is shown;

[0042] Figure 7b The structure of the synchronization mechanism in the die-cutting machine is shown;

[0043] Figure 7c-7f shows various states of the synchronization mechanism within the die-cutting machine; and

[0044] Figure 7g The rotational movement of the two bases of the synchronization mechanism is shown. DETAILED DESCRIPTION

[0045] FIG1 shows the general structure of a 3-layer corrugated board 10. The board includes a first outer layer 11, a middle fluted layer 12, and a second outer layer 13. All layers are usually made of paper, while the middle layer is sometimes made of another type of paper than the outer layers. The three layers are attached to each other by glue. There are also commonly 2-layer, 5-layer, and 7-layer corrugated boards. The system and method of the present invention are applicable to all four types of corrugated boards (2, 3, 5 or 7 layers).

[0046] A general process and machine configuration 100 for producing 5-ply corrugated board is described in Figure 2. This 5-ply description is provided as an example. The general process and machine configuration for producing 2-ply, 3-ply or 7-ply corrugated board is similar, and as noted, the present invention is applicable to corrugator machines for producing corrugated board comprising any number of plies.

[0047] The machine 100 includes five paper feed rolls, which respectively contain a first outer layer 102, a second outer (cover) layer 110, a first fluted (corrugated) layer 104, a second fluted layer 108, and an intermediate cover layer 106. In a first stage, the first outer layer 102 is attached to the first fluted layer 104 by glue. The fluted layer 104 passes through a corrugating mechanism 104a before being attached to the bottom of the first outer layer 102 by glue. Next and similarly, the second fluted layer 108 is attached (by glue) to the intermediate cover layer 106, and then the outer layer 110 is attached to the other (bottom) side of the second fluted layer 108. Next, the integral corrugated 3-layer structure including layers 106, 108, and 110 is attached to the bottom 104b of the fluted layer 104, thereby producing a 5-layer strip 150. Next, the 5-layer strip 150 passes through a heating plate 128, which is configured to dry the glue on the strip. In some cases, particularly in high-throughput corrugators, the drying of the glue is performed by a unit distinct from the main part of the corrugator, which unit is sometimes positioned above the main unit (in which case the strip is returned to the main part for cutting, as will be described in detail below). After the drying stage, the strip passes through two stages, each of which includes two sets of cutting blades: (a) longitudinal cutting blades 130; and (b) transverse cutting blades 126 (two separate transverse cutting blades 126a and 126b are shown as an example). The longitudinal blades 126 and the transverse blades 130 are included as standard in all prior art corrugators 100, resulting in the output production of a plurality of separated sheets 120. The operator of the corrugator 100 can configure the size of the output sheet 120 by adjusting the position and number of blades used; however, the separated output sheets are conventionally a standard product of the corrugator 100, regardless of how many layers are included.

[0048] As described above, the different (separated) sheets are then transferred to a die-cutter designed as a standard to receive separated corrugated cardboard at its input and output separated formed sheets ready to be formed into (for example) three-dimensional boxes.

[0049] Figure 32 shows the overall structure of an improved corrugator 200 according to an embodiment of the present invention. The improved corrugator 200 is substantially the same as the corrugator 100 of FIG. 2 , excluding the longitudinal blade 126 and the transverse blade 130, which are eliminated and do not exist in the improved corrugator 200. Therefore, the "slim" strip 250 is the output product of the improved corrugator 200, and the strip is directly conveyed 222 to the die-cutting machine ( Figure 3 This structure is in contrast to the corrugator 100, in which the separated paperboard 120 is conveyed (or transported) to a subsequent die-cutter.

[0050] Figure 4a The overall structure of the system 1000 according to the embodiment of the present invention is schematically shown. Figure 3 As shown, a plurality of paper liners 202, 204 and 206 are fed into a modified corrugator 200 (which, in this particular case, produces a 3-ply product for creating a 3-D pizza box). Figure 3 The input paper liner is processed as described in the process of , and a multi-layer corrugated elongated strip 250 (in this particular case, a 3-layer elongated strip) is output. The 3-layer corrugated strip 250 is then conveyed to the die-cutter 400, which repeatedly cuts the strip into a plurality of formed plates 402, for example, plates ready for preparing a 3D pizza box. This process is performed continuously and repeatedly, so that the die-cutter 400 pulls and cuts the strip 250 into multiple pieces, and the die-cutter 400 also shapes the multiple pieces, thereby outputting paperboards 402 of different shapes. Cutting the strip into pieces and shaping it can be performed simultaneously with the same template. The die-cutter 400 can use various types of templates known and common in the art, such as a flat template, a rotary template, etc. The input strip 250 may include a pre-print on the top side or the bottom side of the strip, so that the formed plate 402 is ready for use by the end user. Printing may be performed within the modified corrugator 200, or included in a pre-printed outer paper liner 202 or 210. Alternatively, printing may be applied after the die-cutting stage, as is most conventional in prior art corrugator-die-cutting systems.

[0051] Typical prior art corrugating machines do not include built-in printing equipment. In one embodiment, the improved corrugating machine 200 of the present invention may include a built-in printing device 260, such as Figure 6 As shown, the built-in printing device prints on the outer layer 210. The built-in printing device 260 can be a flexographic printing press, an offset printing press, a rotary printing press, or a digital printing press. When operating with a printed strip, the die cutter 400 includes a sensor (e.g., an optical sensor, not shown) that synchronizes the timing of the cutting operation based on, for example, the printing on the strip.

[0052] As noted, conventional die cutters for processing corrugated board are designed to receive separate multiple corrugated boards, rather than elongated strips. Therefore, various adaptations should be made to existing (already sold products) die cutters to receive corrugated board strips. Alternatively, new and compatible die cutters can be produced to receive strips 250. These adaptations are relatively simple because most of the conventional functions of the die cutter remain unchanged. For example, in order to obtain smooth and reliable operation, the inventors have found that adding an optional auxiliary feeder 274 (with, for example, rollers) is preferred. As previously described, in the improved corrugator 200, the transverse blades and the longitudinal blades are eliminated or disabled.

[0053] The die cutter 400 may include a rotary cutter or a flatbed cutter. Both types of die cutting equipment are well known and widely used in die cutting machines.

[0054] In prior art systems, the fact that the corrugator and die-cutter are designed to operate independently (in many cases even remotely from each other) allows each unit (corrugator or die-cutter) to operate at its own speed and throughput without significant impact or necessity for synchronization between them. However, in the system 1000 of the present invention, the two units 200 and 400 must be synchronized to avoid failures, or the two machines must be tuned to operate at exactly the same speed. Figure 4a Such a synchronization unit 1002 is schematically shown in the system 1000 of . Conventional corrugators and die cutters usually have a certain degree of speed regulation, and these adjustments can be used. The inventors have found that preferably, especially when the die cutter 400 utilizes a flat platen die plate, for reliable long-term operation, additional speed compensation must be provided in addition to the conventional speed regulation (in both machines 200 and 400). In contrast to a rotary die plate that performs die cutting continuously, a flat bed die cutter moves its cutting element up and down between two consecutive operations, thereby creating a "pause"; more specifically, a flat bed die cutter operates in a "beat" manner, which is inconsistent with the continuous movement of the strip from the corrugator, which is exactly what is needed in the present system. Figure 5 A synchronization structure is provided that can compensate for such pauses or that can be used in some other embodiments of the present invention.

[0055] Figure 5A type of synchronization of a system 1000 according to an embodiment of the present invention is shown, particularly suitable for a flat-bed die-cutter. A strip 250 is suspended in a buffer zone between the outlet 222 of the modified corrugator 200 and the inlet 422 of the die-cutter 400. As shown, the strip 250 is designed to form a curve by being suspended at a height h above the ground g (h defines the minimum height substantially in the middle distance between the two units 200 and 400). It is assumed that the height h remains constant in normal operation. A laser unit 260 is fixed above the strip 250 and measures the distance d (which corresponds linearly to the height h), transmitting the measured value d to the synchronization unit 1002. When the speed of the modified corrugator 200 increases relative to the speed of the die-cutter unit 400, the height h decreases (meaning that the distance d increases), and the synchronization unit 1002 instructs the corrugator to reduce its operating speed. Alternatively, it can instruct the die-cutter to increase its operating speed. In another case, when the speed of the improved corrugator 200 is reduced relative to the speed of the die-cutting unit 400, the height h increases (meaning that the distance d decreases), and the synchronization unit 1002 instructs the corrugator 200 to increase its operating speed. Alternatively, it can instruct the die-cutting machine to reduce its own operating speed. In this way, using the laser 260 and the reference height h, the synchronization unit 1002 monitors and matches the operating speeds of the units 200 and 400, and compensates for any deviations (including the typical "pause" of the flat-bed die-cutting machine). Various other synchronization structures can be used. Such a synchronization structure can use optical sensors, electromagnetic sensors, pressure sensors, etc. In other embodiments, synchronization can be performed directly between the two units without using an external synchronizer 1002. For example, when a rotatable box is used in the die-cutting machine 400, the external synchronization unit 1002 can be avoided. In this case, the speed signal can be shared between the two units 200 and 400, and used to tune the speed separately in the unit.

[0056] Furthermore, when a rotatable box is used within the die cutter 400, the strip 250 can travel straight and without a curve between the two units, such as Figure 4a As shown. In such a configuration, external synchronization 1002 can also be avoided. A static or dynamic conveyor 272 can also be used between the two units to assist in the movement of the strip. Figure 5 The curve shown saves space because the two machines 200 and 400 can be positioned closer together.

[0057] Figure 7a A system 2000 according to another embodiment of the present invention is shown in schematic block diagram form, which includes a flatbed rotary die cutter. Figure 4aThe numbers 612 indicate similar functions. The die cutter 600 includes a flatbed rotary unit 610 that combines the features of a flatbed die cutter and a rotary die cutter. In contrast to conventional flatbed die cutters that operate in a "beat," the flatbed rotary die cutter 600 operates continuously, even though it includes a flatbed die plate. A synchronization unit 612 synchronizes the speed of movement of the flatbed rotary unit 610 to match the speed of movement of the corrugated (and elongated) strip 250.

[0058] Figure 7b The flat plate rotating unit 610 ( Figure 7a 614 and 616, which are arranged to move in series with each other in a manner described in detail below. The upper base 614 generally supports the replaceable template 615, while the lower base 616 generally supports the plate 637. The plate 637 is optional, as the top flat surface 637 of the lower base 616 may be used instead (or the plate 637 may be an integral part of the lower base 616). Similar to Figure 5 In the flat-bed die cutting machine used in the invention, the elongated strip moves between the upper base 614 and the lower base 616 so that when the two bases are engaged with each other, the strip 250 is cut into one or more formed panels. Each of the bases 614 and 616 is kept horizontal while continuously moving in a rotating manner.

[0059] Each of the bases 614 and 616 is rotatably connected to four drive elements 620a-620d and 622a-622d, respectively, at substantially its four corners (625a, 625b, 625c, 625d of the upper base, and 627a, 627b, 627c, 62dd of the lower base). As shown, each pair of drive elements located at the same base edge (620a, 620b or 620c, 620d of the upper base, and 622a, 622b or 622c, 622d of the lower base) is driven by the same shaft (shafts 621a and 621b for the upper base, and shafts 623a and 623b for the lower base). All four axes are synchronously driven by the same drive source (e.g., an electric motor, not shown); however, the two axes 621a, 621b of the upper base 614 are driven in opposite directions relative to the two axes 623a, 623b of the lower base 616. The rotational directions of the upper and lower axes are set so that the engagement of the template 617 with the strip 250 and the lower plate 637 involves a temporary motion vector in the advancing direction 255 of the strip 250. Subsequently, with continued rotation of the axes 621a, 621b and 623a and 623b, the two bases separate while the strip 250 advances until they reengage and produce a new one or more forming plates 402 ( Figure 5). Of course, each such engagement results in one or more new formed panels 402; the number of panels produced depends on the design of the template.

[0060] Figure 7c to Figure 7f Four states of the flat plate rotating unit 610 are shown. Figure 7c In the first state shown, the two bases are in the most separated position due to the angular state of the drive elements 620a, 620c, 622a and 622c. After the previous production of the forming plate 402, the strip 250 enters the space between the two bases. Figure 7d In the second state shown, the two bases are closer together due to the angular state of the drive elements 620a, 620c, 622a and 622c. The strip 250 has advanced slightly in the space between the two bases (as opposed to the Figure 7c ). Figure 7e In the third state shown, the two bases 614 and 616 engage the strip 250 to produce one or more shaped products 402. Figure 7f In the fourth state shown, the two bases 614 and 616 are separated again due to the angular state of the drive elements 620a, 620c, 622a and 622c. The product 402 to be formed is on its way out of the plate turn unit 610, and a new part of the strip 250 just enters the space between the two bases. Figure 7c to Figure 7f The process continues “endlessly,” repeatedly producing formed product 402 .

[0061] It should be noted that the rotation speed of the synchronization shafts 621 and 623 is carefully adjusted based on the desired size of the formed product 402 and the advancement rate of the strip 250. This process actually produces the opposite rotation of the two bases 614 and 616, such as Figure 7g The upper circle 655 shows the counterclockwise movement of each point on the surface of the template 617 ( Figure 7b ). The lower circle 665 shows the clockwise movement of each point on the surface of the plate 637 ( Figure 7b ). Arrow 675 indicates the temporary movement that occurs at template 617 when engaging strip 250. The motion vector is carefully adjusted to match the speed of strip 250. An indication of the speed of the strip can be obtained, for example, from a sensor positioned adjacent to the strip. It should also be noted that other mechanical arrangements can be applied to the structure of the two plates to obtain circular movement (such as Figure 7g The number of drive elements 620, 622 may also vary.

[0062] Figure 4bAnother embodiment of the system of the present invention is shown, comprising two die cutters 400a and 400b working alternately. In general, a typical die cutter comprises a die plate 267a, 267b, which is a flat plate or a rotary type, defining the shape of the final product. After any die plate change, the die cutter must be fine-tuned (offline, when the die cutter is not working) to adapt to the newly installed die plate. Each such adjustment consumes a lot of working time, tens of minutes, during which the entire system must be shut down. In order to eliminate this shutdown time, Figure 4b The system includes two die cutters 400a and 400b that operate alternately. Before changing the new system operation (i.e., producing another output product), the new template 267b is inserted into the currently inactive die cutter (die cutter 400b in this case). Die cutter 400b is fine-tuned when it is offline and when the system 1000 is still in continuous operation with die cutter 400a. Only when the adjustment of die cutter 400b has been completed, the operation of the system is terminated, the strip 250b is inserted into the entrance of die cutter 400b, and the operation is started again to produce a new product. In a similar manner, the same process can be performed to produce another product while switching back to die cutter 400a. Preferably, die cutter 400b is installed on the top of die cutter 400a, however, this is not necessary. Figure 4b The system structure (with two die cutters) is also suitable for Figure 3 , Figure 5 and Figure 6 design and make necessary improvements.

[0063] Example 1

[0064] As described above, conventional corrugators and die cutters are not designed to interact with corrugated strips. On the one hand, conventional corrugators are designed to output separate multiple boards, rather than elongated strips. On the other hand, conventional corrugator-type die cutters are designed to receive separate boards. As noted, conventional transverse and longitudinal blades (respectively 126a, 126b, and 130 in FIG. 2 ) are eliminated in the improved corrugator 200 of the present invention.

[0065] The inventors have constructed a system 1000 having a curved strip 250 at a buffer zone, such as Figure 5 A 3-layer corrugator model PY 1300 manufactured by Han Da Machinery Co., Ltd. was used. The longitudinal blade and the transverse blade were removed from the corrugator.

[0066] The inventors have found that there is no die cutter 400 on the market that can accept the corrugated strip 250; therefore, an alternative solution must be found. To this end, the inventors used a flatbed die cutter originally designed for the production of disposable tableware, power: 14KW, model #: PY 1300, speed: 30-200 meters / minute, manufactured by Dakiou, CN. Using a die cutter such as Figure 5 The synchronizing unit 1002 in the system, as well as the feeding auxiliary element 274. The blower 262 and the laser 260 are also located above the strip to keep the strip relatively stable during the intensive operation of the system. The pre-printed strip moves at a speed of up to 50 meters per minute, producing 350 pizza boxes per minute. An optical synchronization sensor is used in the die-cutter to correctly cut the pre-printed strip. The distance between the two units is 12m; however, when a flat-bed die-cutter is used, any distance between 3-18 meters can be used. When a rotatable die-cutter is used, the distance between the two units can even be reduced to less than 1m. Distances above or below these ranges may be operational, but are not preferred. For this experiment, the inventor used a corrugator in which one layer was pre-printed. In addition, the glue dryer manufactured by HANDA is located above the main unit of the corrugator to save space. It is estimated that the system of the present invention consumes at least 60% less space than comparable systems of the prior art. The system of the present invention may use standard 1600mm strips, 2800mm strips or any other strip width commonly used. For example, a 1600mm strip is used.

[0067] The inventors believe that replacing the product collection unit at the exit of the die-cutter can reliably increase the speed of the test system to 80 m / min.

[0068] Example 2

[0069] A second experiment was conducted with a system comprising a corrugator having two alternately operated (a) flatbed die cutters and (b) rotary die cutters. The rotary die cutter was positioned on top of the flatbed die cutter together with a glue dryer. In this case, a speed of 50 m / min was obtained when the flatbed die cutter was operating. A speed of 100 m / min was obtained when the rotary die cutter was operating.

[0070] Compared to the weight of a flatbed die cutter, a rotary die cutter generally weighs significantly less. However, while a flatbed die cutter costs about $300, a rotary die cutter costs about $3,000.

[0071] Several simple adjustments are made to the die-cutting flatbed and the rotatable machine. Both machines typically include a sheet feed unit which is no longer necessary in the system of the present invention using the elongated strips. Thus, these feed units are eliminated.

[0072] It has also been found that the system of the present invention is advantageous in terms of saving materials. While approximately 3-5% of the material is typically wasted in prior art corrugated production lines alone, and an additional 7-10% is typically wasted in off-line die-cutting systems, the total waste in the entire (corrugator and die-cutter) system of the present invention is reduced to approximately 3-5%.

[0073] The system of the present invention can typically be operated by 2-3 operators. In contrast, operating a similar prior art system requires about 10 workers, especially if the prior art system is distributed in two geographical locations. The system of the present invention also saves manufacturing space. In the prior art corrugator-die-cutter system, the finished boards from the corrugator must be transported to a warehouse on pallets and then transported to various processing plants for printing and cutting before being shipped to the final consumer. Alternatively, they are placed in a huge temporary warehouse for cardboard, waiting to be put into production on the internal die-cutter. In contrast, in the present invention, no temporary storage warehouse is required because the finished products are produced immediately and can be transferred to the final consumer immediately.

[0074] Although some embodiments of the present invention have been described by way of illustration, it is obvious that the present invention may be implemented through many improvements, variations and adaptations and by using many equivalent or alternative solutions within the scope of those skilled in the art without departing from the spirit of the present invention or exceeding the scope of the claims.

Claims

1. An integrated corrugated forming machine and die-cutting system, comprising: a corrugator configured to produce an elongated, multi-layered moving strip of corrugated paperboard; and A die cutter is configured to receive the strip of corrugated paperboard and repeatedly cut the strip of corrugated paperboard into a plurality of formed panels.

2. The system of claim 1, wherein: The transverse blade and the longitudinal blade are eliminated at the corrugator.

3. The system of claim 1, wherein: The elongated multi-layer strip comprises 2, 3, 5 or 7 layers.

4. The system of claim 1, wherein: The strip includes printing, and wherein the printing is selected from pre-printed, printed in the corrugator, or printed in or after the die cutter.

5. The system of claim 4, wherein: The corrugating machine comprises a built-in printing press selected from a flexographic printing press, an offset printing press, a rotary printing press or a digital printing press.

6. The system of claim 1, wherein: The separate glue drying unit of the corrugator is positioned above the main body of the corrugator.

7. The system of claim 1 further comprising synchronization between a speed of movement of the strip at an exit of the corrugator and an operating speed of the die cutter.

8. The system of claim 7, wherein: The synchronization is performed at a region between the corrugator and the die-cutter using a synchronization unit external to the corrugator and the die-cutter.

9. The system according to claim 8, wherein: The synchronization unit comprises: said strip forming an above-ground curve of predetermined height h; a laser unit which continuously measures said height h and feeds said height to a synchronization entity; and The synchronization entity is configured to receive the height h and adjust the operating speed of one or more of the corrugator or die-cutter to keep the height h constant.

10. The system according to claim 7, wherein: The synchronization is achieved by a die-cutting machine, the die-cutting machine comprising: an upper base and a lower base, wherein the upper base comprises a flat plate template facing downward and the lower base comprises a flat surface facing upward toward the template; a mechanism configured to impart a rotational circular or elliptical motion to each of said upper and lower bases so that, when engaged, said two bases are horizontal relative to the corrugated strip passing therebetween; and A synchronization unit is configured to synchronize, at each engagement time, between the horizontal movement vectors of the two bases and between the speed of the strip moving between the two bases.

11. The system according to claim 10, wherein: The institutions include: a drive element at each of said upper and lower bases; a shaft attached to the drive element; and A motor is configured to impart rotation in an opposite direction to an axis driving the upper base relative to an axis driving the lower base.

12. The system of claim 1 further comprising a feed assist device at an inlet of the die cutter.

13. The system of claim 1, wherein: The die-cutting machine is selected from a rotary die-cutting machine or a flat-bed die-cutting machine.

14. The system of claim 1, further comprising a static or dynamic conveyor between the corrugator and die cutter, the static or dynamic conveyor configured to assist in movement of the strip.

15. The system of claim 1 comprising two die cutters operating alternately.

16. A method for producing formed corrugated paperboard, comprising: providing a corrugator configured to produce an elongated multi-layer corrugated strip; as well as A die cutter is provided and is configured to continuously receive the elongated, multi-layer corrugated strip and cut the strip into separate formed sheets.

17. The method of claim 16, further comprising printing the strip prior to the corrugator, within the corrugator, or within the die-cutter, or printing the separate formed sheets external to the die-cutter.

18. The method of claim 16, further comprising synchronizing an operating speed of the corrugator with an operating speed of the die cutter.

19. The method according to claim 16, further comprising: providing a second die cutter, wherein at any given time at most one of the die cutters is operational and the other is inoperative; When a new job needs to be changed, install the new die in the inoperative die cutter and fine-tune the inoperative die cut; and Start the operation with the newly adjusted die cutter.

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