ARRANGEMENT FOR PRODUCING EMBOSSED CUSHIONING MATERIAL AND METHOD FOR PRODUCING EMBOSSED CUSHIONING MATERIAL
20230278307 · 2023-09-07
Inventors
Cpc classification
B31D2205/0047
PERFORMING OPERATIONS; TRANSPORTING
B31D2205/0058
PERFORMING OPERATIONS; TRANSPORTING
B31D2205/0011
PERFORMING OPERATIONS; TRANSPORTING
B31F1/22
PERFORMING OPERATIONS; TRANSPORTING
B31D5/006
PERFORMING OPERATIONS; TRANSPORTING
B31D5/0043
PERFORMING OPERATIONS; TRANSPORTING
B31D2205/0082
PERFORMING OPERATIONS; TRANSPORTING
B31D5/0069
PERFORMING OPERATIONS; TRANSPORTING
International classification
Abstract
An arrangement for producing embossed cushioning material from an initially flat material comprises an embossing device for providing a plurality of embossed protrusions to the material, an undulating device comprising undulated forming spaces which creates undulations in the initially flat material prior to the undulated material being provided to the embossing device, and a conveying means for conveying the initially flat material along a transport path in a continuous process through the undulated forming spaces. It is that suggested that the undulating device, seen in the direction of the transport path, comprises at least two stages each comprising an undulated forming space, the undulated forming space of a downstream stage differing in number and/or height of undulations from the undulated forming space of an upstream stage.
Claims
1. An arrangement for producing embossed cushioning material from an initially flat material, comprising an embossing device for providing a plurality of embossed protrusions to the material, an undulating device comprising undulated forming spaces which creates undulations in the initially flat material prior to the undulated material being provided to the embossing device, and a conveying means for conveying the initially flat material along a transport path in a continuous process through the undulated forming spaces, characterized in that wherein the undulating device, seen in the direction of the transport path, comprises at least two stages each comprising an undulated forming space, the undulated forming space of a downstream stage differing in number and/or height of undulations from the undulated forming space of an upstream stage.
2. The arrangement of claim 1, wherein a lateral extension of the undulating forming space of the downstream stage is greater than the lateral extension of the undulating forming space of the upstream stage.
3. The arrangement of claim 1 wherein a height of the undulations of the undulating forming space of the downstream stage is essentially identical to the height of the undulations of the undulating forming space of the upstream stage.
4. The arrangement of claim 1 wherein a width of the undulations of the undulating forming space of the downstream stage is essentially identical to the width of the undulations of the undulating forming space of the upstream stage.
5. The arrangement of claim 1 wherein each stage comprises, seen in lateral direction, at least one region which is free of any undulated forming space and which is delimited on both sides by regions-having an undulated forming space.
6. The arrangement of claim 5 wherein, seen in the direction of the transport path, the number of regions which are free of any undulated forming space increases from at least one upstream stage to a subsequent downstream stage.
7. The arrangement of claim 1 wherein the undulated forming space is formed between two counter rotating forming rollers.
8. The arrangement of claim 1 wherein it comprises a crumpling device which crumples the material in a second dimension which is orthogonal to the first dimension.
9. The arrangement of claim 8 wherein the crumpling device comprises a first driven conveying means and a second driven conveying means, the first driven conveying means being upstream when seen in the direction of the transport path, and the second driven conveying means being downstream when seen in the direction of the transport path, wherein each conveying means is designed and arranged to frictionally convey the material along the transport path, wherein in operation the conveying speed of the second conveying means is lower than the conveying speed of the first conveying means.
10. The arrangement of claim 1 wherein the embossing device comprises a first embossing cylinder and a second embossing cylinder, wherein the embossing cylinders are designed and arranged to receive the undulated material between them, at least the first embossing cylinder having a peripheral surface comprising a plurality of protrusions creating embossed protrusions in the material when it is received between the first embossing cylinder and the second embossing cylinder.
11. The arrangement of claim 10 wherein it comprises a separating device which is arranged immediately downstream of the embossing device, and which is arranged and designed to prevent the embossed material exiting from the embossing device from sticking or staying sticked to the embossing device.
12. The arrangement of claim 11 wherein the separating device comprises at least a deflector, wherein the embossing device, seen in lateral direction, comprises a region which is free of protrusions, and wherein, seen in the direction of the transport path, the deflector is essentially aligned with said region which is free of protrusions.
13. The arrangement of claim 12 wherein, seen in the direction of the transport path, a deflector is essentially aligned with a region which is free of any undulated forming space.
14. The arrangement of claim 1 wherein it comprises a folding device which is arranged and designed to fold at least one lateral edge portion of the initially flat material or of the undulated intermediate material inwardly upon itself.
Description
[0037] The invention now will be described with reference to the attached drawing. In the drawing is
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[0050] It is to be noted that for the sake of clarity in the figures only exemplary but not all elements and portions or regions are designated with reference signs. Moreover, functionally equivalent elements and regions have the same reference numerals in different embodiments.
[0051] In the figures, an embossed cushioning material generally has the reference sign 10. As can be seen from
[0052] The second embossed protrusions 14b extend from the reference or middle plane 12 in a second direction 18, the second direction 18 being opposite to the first direction 16. Both directions 16 and 18 are orthogonal to the reference or middle plane 12. The position of the first embossed protrusions 14a and the second embossed protrusions 14b are arranged in an alternating order which means that in a row of protrusions adjacent to a first embossed protrusion 14a there are two second embossed protrusions 14b.
[0053] The embossed cushioning material 10 further comprises a plurality of first creases 20. As can be seen especially from
[0054] In the present exemplary embodiment the embossed cushioning material 10 is made from craft paper. It is particularly preferred that the embossed cushioning material 10 is made from recycled craft paper. The grammage of the initially flat craft paper material is in the range of approximately 40-76 g/m.sup.2, more preferably in the range of approximately 50-60 g/m.sup.2.
[0055] In the present exemplary embodiment a cross sectional shape, when viewed from the side (
[0056] In the present exemplary embodiment a height 26 (
[0057] Reference is now made to
[0058] The arrangement 30 comprises a supply 32 for supplying an initially flat and web-type paper raw material 34. The web-type paper raw material 34 may be provided by way of example as a roll 36 of paper. In an alternative non-shown embodiment the flat web-type paper raw material may be provided as a stack of zigzag folded paper. The flat web-type paper raw material 34 is conveyed along a transport path 38 through the arrangement 30.
[0059] It first passes a tensioning unit 40 comprising two stationary cylindrical rollers 42 and a vertically movable cylindrical roller 44. The vertically movable cylindrical roller 44 puts the flat web-type paper raw material 34 under a certain tension in the direction of the transport path 38 by its weight. However, the tensioning action of the vertically movable cylindrical roller 44 may be further enhanced for example by a spring forcing the vertically movable cylindrical roller 44 downwardly.
[0060] Seen in the direction of the transport path 38 downstream of the tensioning unit 40 an undulating device 46 and an embossing device 48 are arranged. In the present exemplary embodiment the undulating device 46 comprises three pairs 50, 52 and 54 of cooperating forming rollers or devices, respectively, 56a/b, 58a/b, and 60a/b.
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[0062] The general designs of the forming devices 56-60 are similar to each other. This general design therefore will be described hereinafter by way of example with reference to the forming devices 56a/b of the first pair 50 (
[0063] The forming device 56a comprises a shaft 66 on which is arranged a plurality of disk type conically shaped portions 68. The disk type portions 68 are spaced apart from each other and arranged along a longitudinal axis of the shaft such that interstices 70 are formed between adjacent disk type portions 68. The disk type portions 68 of the first forming device 56a mesh with interstices 70 between the disk type portions 68 of the second forming device 56b, the interstices 70 formed between the meshing disk type portions 68 of the forming devices 56a and 56b forming an undulated space 72 creating undulations 74 (
[0064] As can be seen from the figures, the arrangement 30 is able to produce the embossed cushioning material 10 without the need of a pretreatment by means of hot steam prior to creating the embossed protrusions 14a-b. However, it is to be understood that in a non-shown embodiment the arrangement 30 may additionally comprise means for applying hot steam and/or water dust and/or water spray to the initially flat web-type paper raw material 34 prior to feeding the material 34 into the undulating device 46 and/or to the intermediate product 71 (
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[0067] As can be seen from
[0068] As can be seen from
[0069] As can be seen from
[0070] After the web-type paper material 34 has passed the undulating device 46 and after having been transformed into an undulated intermediate web-type paper material 71 it enters the embossing device 48 which comprises first and second rotating and driven embossing cylinders 76a and 76b. The first and second embossing cylinders 76a and 76b are designed and arranged to receive the undulated intermediate paper material 71 therebetween. Both embossing cylinders 76a/b have a peripheral surface 78 comprising a plurality of protrusions and recesses creating the embossed protrusions 14a and 14b as described above with reference to
[0071] A schematic sectional view of the embossed cushioning material 10 downstream of the embossing device 48 seen in the direction of the transport path 38 is shown in
[0072] It is to be understood that the undulations 74 of the undulated web-type paper material 34 as shown in
[0073] As can be seen from
[0074] The forming devices 56a-60b of the pairs 50-54 of the undulating device 46 and the first and second embossing cylinders 76a/b of the embossing device 48 are driven with specific rotational speeds. The rotational speeds of the forming devices 56-60 are selected such that the web-type paper raw material 34 is conveyed through the undulating device 46 with a uniform speed in the direction of the transport path 38. The undulating device 46 and the embossing device 48 therefore form first and second conveying means.
[0075] In contrast hereto, the rotational speeds of the first and second embossing cylinders 76a and 76b on the one hand and the rotational speeds of the forming devices 60a/b of the third pair 54 on the other hand are selected such that the undulated web-type paper material 34 and 71, respectively, is conveyed through the embossing device 48 along the transport path 38 at a lower speed than through the undulating device 46. This results in a crumpling action applied to the undulated web-type paper material 34 in longitudinal direction 22, which extends parallel to the direction of the transport path 38. By consequence, the third pair 54 of cooperating forming rollers 60a and 60b and the embossing device 48 with its first and second embossing cylinders 76a and 76b form a crumpling device 80.
[0076] The crumpling action of the crumpling device 80 results in a reduction of the dimension (second dimension) of the undulated web-type paper material 34 in the longitudinal direction 22 by approximately 10%. The reduction of the dimension of the undulated web-type paper material 34 in the longitudinal direction 22 results in the creation of second undulations which are pressed by the first and second embossing cylinders 76a/b into the above mentioned second creases 25. The second creases 25 extend essentially orthogonally to the first creases 20.
[0077] While with reference to the figures an embodiment of an arrangement 30 has been described which is intended to be stationary, it is to be understood that the technical principles of the arrangement 30 might be integrated also in a small and compact mobile device which may be arranged close to the location where a user uses the embossed cushioning material 10 for wrapping and protecting an article. In order to reduce the horizontal dimensions of such a mobile device, the supply for supplying the flat web type paper raw material, the undulating device and the embossing device may be arranged vertically above each other, and the transport path of the flat web type paper raw material as well as of the intermediate product may comprise horizontally as well as vertically extending portions.
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[0079] More specifically, the lateral extension of the undulating forming space 72, that is the extension orthogonally to the direction of the transport path 38 and being essentially in the plane of the flat web type paper material 34, increases continuously from the first stage 50 to the fifth stage 84. This is realized simply by adding disk type portions 68, while in the present exemplary embodiment all disk type portions 68 of all stages 50-54 and 82-86 are identical. This results in a height of the undulations of the undulating forming space 72 being essentially identical in all stages 50-54 and 82-86 of the undulating device 46. The “height” of said undulations physically corresponds to an “amplitude” of the undulations.
[0080] Moreover, the design of the undulating device 46 results in a width of each undulation of the undulating forming space of all stages 50-54 and 82-86 being essentially identical. The “width” of an undulation physically corresponds to a “wavelength” of the undulations.
[0081] As can be seen especially from
[0082] As is apparent from
[0083] In order to ease the operation of the deflectors 94, the deflectors 94 are essentially aligned both with the regions of the stages 50-54 and 82-86 of the undulating device 46 and with regions (not visible in the drawing) of the embossing cylinders 76a and 76b of the embossing device 48 which are free of protrusions and cavities, when seen in lateral direction. This provides for an essentially flat surface at the embossed cushioning material 10 at the location of the deflectors 94, this flat surface having no embossed protrusions and at least less first creases 20.
[0084] Finally, as can be seen from
[0085] An embossed cushioning material 10 which can be produced with the arrangement 30 of
[0086] While the central region 120 in the present exemplary embodiment comprises one single material layer, both lateral edge regions 118 comprise two adjacent material layers. These double layer lateral edge regions 118 are formed by a 180° fold 119 of the single material layer extending from the central region 120 towards the lateral edge regions 118. The fold 119 forms the outer lateral edges of the sheets 112. In the arrangement 30 of
[0087] As can be seen from
[0088] It is, however, to be understood that the width of the lateral edge region 118 may vary along the length of the embossed cushioning material 10, that is along the longitudinal direction 116, as is shown in
[0089] The embossed cushioning material 10 in the present exemplary embodiment comprises a longitudinally extending strip shape region 126 which is free of protrusions 14a/b and which is delimited on both sides by the areas 124 having protrusions 14a/b. In the present exemplary embodiment, one sheet 112 of embossed cushioning material comprises one single and, with reference to the lateral edge regions 118, centrally located strip shape region 126 extending from a leading edge (without reference sign, in
[0090] The presence of the strip shape region 126 has the following reason: when the flat web-type paper raw material passes through the embossing device 48 with its embossing cylinders 70a/b, the material is received and deformed between the walls of the embossing cavities and the matching embossing protrusions of the embossing cylinders 70a/b. When the deformed material leaves the gap between the two embossing cylinders 70a/b, it has a certain tendency to stick to one of these cylinders 70a/b.
[0091] In order to prevent the embossed cushioning material 10 from sticking or staying sticked to the cylinders 70a/b, the arrangement 30 and specifically the embossing device 48 comprises the above mentioned separating means 92 which is arranged adjacent the embossing cylinders 70a/b immediately downwardly of the embossing cylinders 70a/b. These separating means 92 with its deflectors 94 comes into sliding contact with the embossed cushioning material 10 and lifts the material off an embossing cylinder 70a/b, if the material 10 remains sticked to one of these cylinders 70a/b.
[0092] This separating means 92 is arranged, seen in lateral direction of the embossed cushioning material 10, at the same location where the strip shape region 126 is located, that is where on the embossing cylinders 70a/b no embossing protrusions and matching cavities are present. Thus, the deflector means 128 cannot contact the cushioning material in the areas 124 having the protrusions 14a/b, but rather and only in the strip shape region 126 being free of any protrusion 14a/b and therefore being relatively smooth and even. By consequence, the strip shape region 126 being free of protrusions 14a/b prevents the deflector means 128 from damaging the embossed cushioning material 10 by interfering with any embossed protrusions 14a/b.
[0093] As has already been mentioned, the lengthy web 110 of embossed cushioning material 10 comprises sheets 112 separated by perforation lines 114. These perforation lines extend crosswise, that is orthogonally to the longitudinal direction 116. A perforation line 114 is formed by material bridges 130 and material slits 132. The material slits 132 are located between the material bridges 132. By consequence, along the length extension of a perforation line 114, material bridges 130 and material slits 132 alternate. In the present exemplary embodiment, the perforation line 114, that is the material slits 132, has been cut into the “final” embossed cushioning material after the undulating and embossing steps.
[0094] In the present exemplary embodiment shown in
[0095] As can be seen from