FIELD

[001] The present disclosure teaches a process for making domed paper for use in applications such as packaging or envelopes as that further described by De Luca et al. in US Patent 931531B2 “Domed Multilayer Cushioning Article” as well as by De Luca et al. in US Patent 10,870,949 “Manufacturing Process for Forming Domed Paper” and US Patent Publication 2021/0122504 “Integration of a Liner Within an Automated Process for Filling”. The process incorporating those elements and further including means for forming the domed paper using a continuous process instead of a process that requires the web and paper to stop moving during the pressing.

BACKGROUND

[002] Void fill paper cushioning, cushioning wrap, and envelopes with liners are commonly used for the purpose of mailing and shipping packages. In US patents US5454642 and US6116000 De Luca describes various methods for integrating air cushioning products with boxes or envelopes. In US Patent 931531B2 “Domed Multilayer Cushioning Article” as well as Patent 10,870,949 “Manufacturing Process for Forming Domed Paper”, De Luca describes a paper dome cushioning product that can be formed and integrated within an envelope. In US Patent Publication 2021/0122504 “Integration of a Liner Within an Automated Process for Filling” De Luca describes a system for forming mailers and further filling said mailers.

[003] In all these systems, the formation of the domed paper requires that the paper be registered in a location with respect to the die press such that the pressing plate registers with the cuts on the paper. In order to improve cost efficiencies, the forming presses used are large in nature, requiring approximately 1-5 pounds per square inch of pre-pressed substrate in order to form the dome. With single stamping sizes as large as 12-20 square feet per press, many thousands of pounds of force from the press are required to form the domes. Such high forces require heavy presses that can weigh upwards of 5-10,000 lbs and thus the increase of production capability by using many of such large presses can be difficult. Further, if trying to place pressing systems to form the domed material at e-commerce shipping facilities or facilities that are smaller such as a distribution storage, a large press is not feasible for most applications.

[004] Another difficulty associated with using large press dies that cycle intermittently is that each die generally needs to have its own internal heating system and control system. Further, large dies require significant power (on the order of 3-6 kw) and as the dies are mounted to the presses, a cooling system or cooled interface may be required to prevent heat from transferring to the press. If unmitigated, the heat can cause the press to bind and “lock” due to the difference in expansion rates of various press components including plates and posts.

[005] When forming the domes per US Patents 931531B2 “Domed Multilayer Cushioning Article” as well as Patent 10,870,949 “Manufacturing Process for Forming Domed Paper” and US Patent Publication 2021/0122504 “Integration of a Liner Within an Automated Process for Filling” the substrate is located below the press, stopped, pressed, and then moved. Domes made from a substrate with two layers of kraft paper ranging in thickness from 0.003- 0.007 inches, (ie. 301b-701b basis weight) and pressed at a temperature of approximately 375 degrees F will require approximately 3-4 seconds for a 0.005” layer of starch based adhesive between the paper layers. By increasing the platen temperature, and decreasing the adhesive thickness, press times closer to 1-2 seconds have been achieved though consistency in product produced is more difficult to achieve.

[006] Once the pressing is complete, the paper needs to be indexed forward and moving the paper requires that the paper be accelerated from a resting position. For a press length of 36”, the average speed achieved during movement (through acceleration and deceleration) is approximately lft/second, thus requiring approximately 3 seconds to index forward. Moving the paper faster by increasing the acceleration and velocity profiles can cause the paper to rip and produce inferior product. Correct registration under the die of the indexed substrate further requires 0-2 seconds as the material has to be moved at a slower velocity in order to match the registration marking with the sensor. Overall, the moving and registration process can take as long or more time than the press time and thus is a major contributor to the overall production time and cost to make the product.

[007] One of the more obvious proposed solutions to removing the time associated with the indexing and registration step in forming the domes is to press the substrate between two or more continuously moving heated dimpled rollers. While this would seem to be a plausible solution, the registration of the material with respect to the die pattern is an inherent obstacle to using this technique. This difficulty is associated with the fact that as the paper is being pressed it can no longer be moved or adjusted in position with respect to the die. As such, an offset mismatch of a very small amount cumulatively adds together to form sequences of mismatched and matched press and paper segments.

[008] It is therefore a primary objective of the following invention to provide a manufacturing process able to form domes per US Patent 931531B2 and US Patent 10,870,949 and US Patent Publication 2021/0122504 “Integration of a Liner Within an Automated Process for Filling”, wherein said process is continuous.

[009] It is another objective of the invention that the process allow for continuous registration between the pressing dies and the substrate without requiring the substrate to stop moving.

[0010] It is further an object of the following invention that the process be easily scalable.

[0011] It is another object of the invention that the forming of domes using a smaller footprint die be economical.

[0012] It is another object of the invention that a complete pressing system that can form the domed material be small enough and capable of operating in a just in time manner to be placed within an ecommerce or small distribution facility.

SUMMARY

[0013] The present teachings describe a process for making a paper domed material that is continuous and registered using smaller dies that move with the material.

[0014] ]A process and system for forming domes or protrusions from a sheet in a continuous manner including moving a die set that selectively registers with a sheet, where the die set moves independently from the substrate until the time it latches to the substrate and presses the one or more domes or protrusions for a period of time.

[0015] In some embodiments, the die set latches to a moving belt with the substrate sandwiched between the die set and the belt. The die set is maintained in a pressed configuration so as to form the domes in the substrate. After the domes are formed, the moving die set releases from the belt and the substrate (at the time the material has been formed) and the die set moves away from the pressed dome material and the belt. The belt may function as a backing plate when the die set is pressed into the substrate. In some embodiments, a backing plate other than the moving belt may be provided.

[0016] In some embodiments, auxiliary mechanisms may be attached for use during the pressing. In some embodiments, auxiliary mechanisms for use after the pressing may be provided. Exemplary auxiliary mechanisms may include one or more perforation cut knifes, envelope formers or the like.

[0017] In some embodiments, the die set may be heated and temperature controlled independently or a convective, radiative, or conductive heater may be placed adjacent to the moving die such that multiple dies can be heated with the same heater as each die moves. [0018] In some embodiments, a pneumatic or electric actuation system to press the die set may also move with the die set or a single actuation device can be used to press each of the smaller dies. In some embodiments, the die set may be pressed into a foam material and/or into a negative molded part.

[0019] In some embodiments, the engagement of the die set to the belt and substrate uses an engagement mechanism. An exemplary engagement mechanism may include a rotational lever that moves just before the engagement is to occur such that the belt and substrate can slip between the die set and the belt backing until the correct instant that the die set is supposed to press. The engagement mechanism when activated may interfere with the backing plate of the belt in such a way to allow for engagement during pressing and separation of the die set from the plane of the belt and substrate at the end of the cycle. In some embodiments, more than one engagement mechanism may be used for each die set. The more than one mechanism may be moved in unison.

[0020] In some embodiments, the movement of the engagement mechanism or the die set movement mechanism or temperature control of the die set is done remotely via a method such as Bluetooth. In some embodiments, the correct moment to press is determined using a visual element such as a mark or cut on the substrate. The system using sensors to detect the correct press point or time that comprise one or more of the following: a laser, a proximity sensor, a capacitance sensor, a camera, or an infrared sensor.

[0021] The movement of the die set involving one side of the die set always “facing” the same direction towards belt.

[0022] Any cabling and pneumatic lines may be placed so as to not interfere with the rotation including centered within the path of the die sets. In some embodiments, the path of the die set includes an acceleration zone where the die set is not attached to the substrate or belt. The die set may move faster than the belt so as to get into pressing position as quickly as possible.

[0023] In some embodiments, the path of the die set and substrate are the same along a circular path or a linear path. In some embodiments, the path of the die set moves in steps and includes means for transitioning via gate plates.

[0024] In some embodiments, multiple die set plates are used on the system. In some embodiments, the width of each die set plate is a fraction of a common perforation or cut length. Exemplary widths of a die set plate may be 1/6, 1/5, ¼, 1/3, 1/2 or the like width of a cut pattern length.

[0025] In some embodiments, the press actuation is in a radial manner and on the same radius as the path of the substrate movement. In some embodiments, the die sets include balls. In some embodiments, the die sets can be modified to allow for forming pockets of selectively formed items. In some embodiments, the input material comes on a roll.

Exemplary handling of the roll may be as disclosed in per co-pending PCT Application No PCT/US22/72333 (“Method and System for Forming Domed Paper and Structures”) or US patent No 9315312 or US patent No 10870949.

[0026] In some embodiments, the substrate is moistened or steamed prior to pressing or an adhesive applied or activated. In some embodiments, the die set includes means for simultaneously cutting a pattern on the substrate and then pressing the substrate. In some embodiments, the machine includes a means for maintaining the substrate isolated from air or oxygen. In some embodiments, the machine includes a means for maintaining the substrate at a constant temperature or humidity.

[0027] It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are intended to provide further explanation of the invention as claimed.

BRIEF DESCRIPTION OF THE FIGURES

[0028] The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention, and together with the description serve to explain the principles of the invention.

[0029] Figure 1 is a photograph of a substrate ready to be pressed as described in patents US Patent 931531B2 and 10,870,949 by De Luca.

[0030] Figure 2 is an isometric view of the exterior of the novel continuous forming system.

[0031] Figure 3 is an isometric view of the interior of the novel continuous forming system showing multiple die units.

[0032] Figure 4 is a photograph of a single die positioned to engage and form the substrate within the novel continuous forming system.

[0033] Figure 5 is an isometric view of the interior of the novel continuous forming system further detailing the primary components.

[0034] Figures 6A, 6B, 6C, 6D, and 6E are isometric drawings of the novel continuous forming system further illustration the motion of the dies within the unit.

[0035] Figure 7A is an isometric drawing of the primary gating positions for a die system within the novel continuous forming system. [0036] Figures 7B and 7C are photographs of the gating and actuation systems of the novel continuous forming system.

[0037] Figure 8A is a photograph illustrating the pressing actuation system for a die within the novel continuous forming system.

[0038] Figures 8B, 8C, and 8D are isometric drawings showing alternative pressing actuation systems incorporating a rotary actuator.

[0039] Figure 9 is an isometric drawing illustrating the location of heaters placed in order to heat the dies.

[0040] Throughout the drawings and the detailed description, unless otherwise described, the same drawing reference numerals will be understood to refer to the same elements, features, and structures. The relative size and depiction of these elements may be exaggerated for clarity, illustration, and convenience.

DESCRIPTION

[0041] The present teachings disclose a novel process for forming paper or other material with domes or protrusions.

[0042] Figure l is a photograph of a substrate ready to be pressed as described in patents US Patent 931531B2 and 10,870,949 by De Luca. Substrate 1 is formed from sheets 2 and cut with pattern 3. Cut registrations into the paper such as 3 or 4 can be used for locating the substrate 1 with respect to a press. Further, mark 5 that is printed on the paper using a non- VOC based ink and further printed so as to register with the horizontal locations 500 of cut patterns 3, 6 may alternatively be used to register the substrate to the press.

[0043] Figure 2 is an isometric view of the exterior of the novel continuous forming system. Substrate 1 is formed into a continuous roll and placed adjacent to or under machine system 20. In this example, finished domed material 22 exits at the top the equipment 20 and moves in direction 24. Machine system 20 could also be placed such that direction 24 is more horizontal or angled in a manner to better suit the intended application of the end customer. In the vertical configuration shown in Figure 2, the machine 20 is supported in the vertical position by rails and stand 25 with enclosure 21.

[0044] Figure 3 is an isometric view of the interior of the novel continuous forming system 20 illustrating multiple die sets 33 riding along channels 36 located on plates 35. Gears 32 drive chains 31 used to support the backing plate 37 that multiple dies 33 press into via pistons 34 so at to form finished product 22 with domes 30. Dies 33 may be machined from a solid block of metal, cast using a technique such as sand casting, or formed by attaching via screws domed spheres. In addition, additive manufacturing techniques such as laser sintering can be used to make the dies. Dies can be integrated with heaters, sensors, perforation blades, or other components such as cutting dies or punch dies.

[0045] Figure 4 is a photograph of a single die positioned to engage and form the substrate within the novel continuous forming system. Backing plates 37 are lined on surface 40 with a soft high temperature foam such as a silicone foam and move along with die 33 after engagement. Plates 600 help to maintain the perpendicularity of the die 33 with respect to plates 35 as they move.

[0046] Figure 5 is an isometric view of the interior of the novel continuous forming system further detailing the primary components such as the upwards forming channel 41 and the downward return channel 42. These channels can be machined into plates 35 or molded such that die 33 can move freely.

[0047] Figures 6A, 6B, 6C, 6D, and 6E are isometric drawings of the novel continuous forming system further illustration the motion of the dies within the unit. Position 50 in Figure 6A of die 33 is the engagement point when the pistons 34 or other engagement device actuates the die to engage with the belt formed by chain 31 and supports 39 and sandwiches substrate 1 in a registered position. Such position being determined by sensor 601 detecting printed registration marks 5 or cuts or physical detents such as 4 and or the cut pattern itself as 3 (as shown in figure 1). The activation sequence may be delayed with respect to the actual time the sensor detects the registration signal so as to account for any delay in physically moving the die 33. Once die 33 is engaged with and locked with the support back 39, it moves along channel 41 in parallel to direction of force applied by chain 31. As the substrate 1 and the die 33 move through position 51 and 52 in figure 6B and 6C respectively, heat and pressure continue to be applied to form the cavities or domes 30. When the die 33 reaches position 53 shown in figure 6D, it is disengaged from support backing 39 and foam 40 on surface 37, thus releasing the substrate 1 in its completed formed state 22. Die 33 is subsequently moved into channel 42 to move to position 54 where it is staged in position 55 of figure 6E and moved forward for reengagement in area 56 prior to position 50 of figure 6A. The time taken for die 33 to move from position 50 to position 53 corresponds to the speed of chain 31 and further corresponds to the heat and pressure required to transfer the correct energy to substrate 1 to form 22. One or more sensors 605 generally located within enclosure 21 can monitor temperature, humidity, pressure, speed, and other factors associated with the quality of product 22 formed and using controller 606 can adjust the associated control factors to insure proper consistency.

[0048] Figure 7A is an isometric drawing of the primary gating positions for a die system within continuous forming system 20. Cut slots 60, 61, 62, 63, 64, and 65 are used to stop or allow movement of die 33 between positions along the path formed by channels 41 and 42 and areas 56 and 53. In photographs shown in figures 7B and 7C, plates 606, 607, and 608 are located in slots 66, 67, and 68 respectively and moved with a piston 80 as shown in figure 7C and precisely control when the die is to engage or disengaged or move to a staging position such as position 70.

[0049] Figure 8A is a photograph illustrating the pressing actuation system at position 50 along area 70 for die 33 within the novel continuous forming system 20. While pistons 34 of figure 3 and 5 are mounted on each of the dies 33, piston 90 of figure 8A is mounted to plate 35 and remains stationary rather than moving with the dies. Figures 8B, 8C, and 8D are isometric drawings illustrating alternative pressing actuation system which is mounted on each die 33 using a rotational mechanism incorporated in piston 100. At time of pressing, the mechanical lever 102 moves from an open position 103 with extended shaft 101 of piston 100 to that of rotated lever 104 and retraction of piston 100 shown at 105. This engages the die 33 to plate 39 such that the compression force and strain is confined between the die 33 and plate 39 and not transferred to the side plates 35. This further helps to reduce costs of the overall system and reduces the weight and size of the system 20 compared to a conventional platen press.

[0050] In figure 9, heaters 200 are illustrated as being located along the outside of channel 42 such that the dies 33 can be heated along their motion to starting position 50.

Heaters 200 may be formed of one or more types including radiant heaters, hot air convective heaters, hot liquid baths, hot rollers, electrical resistance or may include electrical contacts to activate a heater within the die. Based on the number of dies required (which in most cases is more than the distance between positions 50 and return area 53 divided by the length along the direction defined by path 41 of die 33), the speed of the chain 31 system, and the material properties of substrate 1, the power transferred to the dies can be adjusted. In the case of using a radiative heat transfer, the backing 610 of die 33 may be covered with a heat absorbing black paint.

[0051] The examples presented herein are intended to illustrate potential and specific implementations. It can be appreciated that the examples are intended primarily for purposes of illustration for those skilled in the art. The diagrams depicted herein are provided by way of example. There can be variations to these diagrams or the operations described herein without departing from the spirit of the invention. For instance, in certain cases, method steps or operations can be performed in differing order, or operations can be added, deleted or modified.