GB2039342A - Rolls for use in corrugated fibreboard production and processing machines - Google Patents

Abstract

A roller 1 with various uses in machines for the production of corrugated fibreboard is formed with its outer surface having a degree of elasticity. In the illustrated case this is achieved with tubes 12 wound helically on roll body 11 from the middle outwards and inflatable through passages 13, if desired with a rotary joint. Instead of passages 13, a syringe may be employed. Other embodiments have only a single helical tube, a plurality of circumferential tubes, tubes extending longitudinally of the roll, either parallel to or at a small angle to the axis of the roll. Solid resilient cords can be used instead of the tubes. Other embodiments use one or more sheaths around the body 11, and these may define one or more inflatable spaces, may incorporate air cells or bubbles, or may be of cellular material. Reinforcements may be incorporated in such sheaths. <IMAGE>

Description

SPECIFICATION Rolls for use in corrugated fibreboard production and processing machines This invention relates to rolls for use in corrugated fibreboard production and processing machines.

The present invention is more particularly concerned with rolls of the type used as a rider roll in the glueing section of a corrugating machine, as a weight roll in a heating (or drying) section of such a machine, as a feed roll arranged before a rotary cutter, and/or as a feed roll in a corrugated fibreboard processing machine such as a printer, a folder-gluerand a rotary die cutter.

Generally, single-faced or double-faced corrugated fibreboard is liable to have its corrugations crushed or deformed when nipped between rolls.

This tendency is marked particularly when the web material used as the facing liner or liners is thin.

In the corrugated fibreboard industry, it has heretofore been a difficult problem to prevent such deformation of the currugations, thereby maintaining constant the thickness of currugated fibreboard.

In the glueing section of a corrugating machine for producing corrugated fibreboard, a glue roll is provided to apply glue to the peaks of the corrugations of a single-faced corrugated fibreboard web fed from a preceding section of the machine. Above this glue roll is a heavy rider roll made of steel. The rider roll has its shaft supported by a lever and is usually set to press the web lightly against the glue roll to prevent poor glueing due to uneven glue application.

The rider roll presses the web from its liner side. In addition to unevenness due to irregularity in the flute height (sometimes called "high-low") arising during the corrugating process, the liner surface usually is uneven and tends to be lower at the areas facing the bottoms of the corrugations than at the areas facing their peaks. Further, the conventional rider roll contacts the web substantially on a line or tangentially. Therefore, the rider roll is usually set for its bottom to contact the lower areas of the liner or is set at an even lower position for secure glueing. The lever mechanism supporting the rider roll is provided with a stop to prevent the rider roll from lowering from its preset position. The lever mechanism is such as to allow upward movement of the rider roll but in practice it is too heavy to be moved upwards by the material being processed.Because the arrangement is such as mentioned above, the corrugations are deformed to a greater or lesser extent when the currugated fibreboard web is nipped between the glue roll and the rider roll.

Also, with the conventional rider roll made of steel, since it has to be set so as to press lightly against the web, there is a tendency for more than necessary amount of glue to be applied to the peaks of the corrugations. This is bad economy and means that the single-faced web absorbs an excessive amount of moisture.

Excessive moisture absorption is undesirable for various reasons. Firstly, the currugated fibreboard web can soften so much, owing to excess moisture, that it becomes more liable to have its corrugations deformed when passing between the rolls at the succeeding steps.

Secondly, the web requires to be supplied with correspondingly more heat at the heating section which follows the glueing section. This represents a waste of heat energy. Also, the web has to stay in the heating section for a longer time. This decreases the machine speed and reduces the production per unit time. Furthermore, the pressure applied to the web, against the usual heating plates in the heating section, has to be increased for better heat absorption. This also makes the web more liable to have its corrugations deformed.

Additionally, excess moisture makes the corrugated fibreboard web more liable to warp or deform, which can cause machine breakdown and/or result in defective web production.

Whenever there is a change in the liner used, the clearance between the glue roll and the rider roll has to be readjusted. This arrangement is very troublesome and requires a high degree of skill. Readjustment of the clearance is also required when the type of corrugation or flute changes. Therefore, a particu- lar set consisting of a rider roll and a glue roll, having an appropriate preadjusted clearance, is usually prepared for each type of flute.

At the heating section of the corrugating machine, a series of weight rolls, made of steel, are arranged to press the corrugated fibreboard web against the heating plates through a cotton belt for efficient heat conduction. Each weight roll has its shaft supported by a lever or a wedge adapted to allow adjustment of the pressure applied to the web by the respective weight roll.

The greater the pressure applied by the weight rolls to the web, the better is the glueing, and a higher machine speed can be expected, but the greater is the possibility of causing deformation of the corrugations. Since the weight rolls press the web through the cotton belt on a line, or tangentially, the pressure applied to the web is considerable even though the web is not pressed directly but is pressed through the cotton belt.

Joints in the cotton belt, where the belt ends or sections are joined, as by lacing or the like, result in bulging portions, and when these pass under the weight rolls, the rolls will skip, thus applying excessive pressure to the web and causing deformation of its corrugations.

At the heating section, too, the clearance between the weight rolls and the heating plates has to be readjusted according to changes of flute type, material, and so on, of the corrugated fibreboard web.

The deformation of the corrugations is most likely to occur at the stages where the web contains a relatively large amount of moisture, i.e. at the glueing section and the heating section.

A pair of feed rolls, made of steel are, usually arranged upstream of a rotary cutter in a corrugating machine, to feed the corrugated fibreboard web toward the rotary cutter. These feed rolls are rotated at a slightly higher speed than the feed speed of the web, to feed the web without letting it accumulate before the rotary cutter. Thus, the web is fed to the rotary cutter while being dragged slightly by the feed rolls.

With conventional steel feed rolls, the upper and lower feed rolls contact the corrugated fibreboard web substantially tangentially on a transverse line.

Therefore, in order to feed the web while dragging it slightly, the pair of the feed rolls has to nip the web with a considerable pressure, thus causing deformation of the corrugated fibreboard web.

Pairs of steel feed rolls are also used in other corrugated fibreboard processing machines such as printers, folder-gluers and rotary die cutters. On these machines, too, deformation of the corrugations can occur as a result of nip force applied by feed rolls. Also, deformation can occur at auxiliary feed rolls and processing rolls provided in such processing machines.

An object of the present invention is to provide an improved form of rolls for use in corrugated fibreboard production and processing machines as aforesaid having a degree of elasticity at the outer periphery appropriate to avoid deformation of the corrugations without the need of frequent readjustment of the clearance between the rolls according to the change of the material, flute type, and so on as discussed above.

With this object in view, the present invention provides a roll for use in a corrugated fibreboard production and processing machine characterised in that said roll has elasticity at its outer periphery.

The roll ofthe invention preferably comprises a roll body and at least one flexible but not permeable tube disposed on the roll body so as at least partially to cover the surface of the roll, said tube being adapted to be inflated by forcing gas therein.

The invention will be described further, by way of example, with reference to the accompanying drawings, in which: Figure 1 is a schematic view showing rolls according to the present invention used in the glueing section and the heating section of a corrugating machine; Figure 2 is a schematic view showing the roll of the invention in use in a succeeding section of the corrugating machine; Figures 3 to 18 are partly cutaway views illustrating sixteen various embodiments of the roll of the present invention; Figure 19 is a sectional view of a variant of the embodiment of Figure 18; and Figure 20 is a sectional view of another variant of the embodiment of Figure 18.

In the drawings, like or the same reference numerals are used to designate like or corresponding parts throughout.

Figure 1 shows a glueing section A and a heating section B of a corrugating machine where rolls 1 according to this invention are used as rider rolls and weight rolls respectively.

The glueing section A comprises generally a glue pan 2, a glue roll 3 partially immersed in the glue in the glue pan 2, a doctor rail 4for adjusting the amount of the glue applied to the glue roll 3, and a rider roll 5 which is one of the rolls 1 conforming to the invention and which rotates in contact with the glue roll 3 with a single-faced corrugated fibreboard web S nipped therebetween to be glued.

A facing sheet or liner L is adhered on to the thus glued web S and the resultant double-faced web S' is then dried at the heating section B where it is pressed by weight rolls 6 against heating plates 7 through a cotton belt 8.

Figure 2 shows a section of the corrugating machine where the double-faced corrugated fibreboard web S' (e.g. as received from the heating section B of Figure 1) passes through a slitter-scorer C and is fed by a pair of feed rolls 9, 10 to a rotary cutter D. The lower feed roll 10 may be replaced with a guide plate. The upper feed roll 9 is usually set to rotate at a slightly higher speed than the speed of the web to pull it.

Although in the example of Figure 1 a roll 1 according to this invention is used only for the upper feed roll 9, it may be used for both the feed rolls or only for the lower feed roll 10.

The details of various alternative embodiments of the roll according to the invention are illustrated in Figures 3 to 20.

A first group of the embodiments is illustrated in Figures 3 to 7. Each is a roll which includes a roll body around which is or are one or more tubes each made of natural or synthetic rubber or a synthetic resin or plastics material having flexibility but not having gas permeability, said tubes being adapted to be inflated by forcing gas therein, to give impart elasticity to the periphery of the roll.

Referring firstly to Figure 3, the roll 1 here shown comprises a roll body 11, and two tubes 12 spirally wound around the roll body 11, said roll body 11 having a gas supply passage 13 for enabling gas, such as air, to be pumped into the tubes 12. Each tube end may be connected to the passage 13 by means of a respective joint which serves also as means for securing the tube 12. The tubes 12 may be secured by any other suitable means, such as adhesives or adhesive tapes.

The gas may be forced into the tube through a hose (not shown) connected to the gas supply passage 13 through a rotary joint (also not shown).

The roll body 11 is provided with spiral grooves 15 in its outer periphery to pertially receive the tubes 12 for secure location of the tubes 12 into which air has been forced.

The embodiment of Figure 3 has two tubes 12 wound spirally around the roll body 11 in opposite directions, starting from the centre toward each end, and such an arrangement serves effectively to prevent the web from running out of true.

The embodiment of Figure 4 is substantially the same as the embodiment of Figure 3 except that it comprises a single tube 12 spirally wound around the roll body 11 in one spiral groove 15 in a single direction. Even when the operational speed of the roll 1 is higher or its width is relatively small, the web does not run out of true although the tube 12 is wound around the roll body 11 in a single direction, as in this embodiment.

The embodiment of Figure 5 comprises a roll body 11 provided with a plurality of annular or circumferential grooves 15 in its outer periphery and a corresponding number of annulartubes 12 mounted one in each of said annular grooves 15.

In the embodiments of Figures 3,4 and 5, gas may be supplied through one or more gas supply ports 14 each having a respective plug as will be described later with reference to Figures 6 and 7. Then, the passage 13 and the rotary joint are not needed, of course.

The embodiment of Figures 6 comprises roll body 11 and a plurality of tubes 12 mounted on the roll body 11 parallel to one another and to the axis of the roll body 11, each of said tube 12 being provided with a respective gas supply port 14 having a plug.

In the embodiment of Figure 7, a plurality of tubes 12 are mounted on the roll body 11 so as to extend at an angle with respect to the axis of the roll body 11.

The embodiments of Figures 4 to 7 may each be provided with the gas supply passage 13, the grooves 15, joints for connecting the tubes 12 with the gas supply passage 13, and a rotary joint for connecting a hose with the gas supply passage 13 as the necessity arises, as has already been described in relation to preceding embodiments.

Instead of supplying gas through a plugged gas supply port 14, the gas may be injected into the tube 12 using an injector or a syringe, if the wall thickness and material of the tube 12 are such as to insure gas-tightness after the injector or syringe has been withdrawn from the tube 12.

In the embodiments of Figures 3 to 7, the distance between the adjacent tubes 12 or tube helices should be such as not to interfere with normal feeding of the corrugated fibreboard web.

Next, a second group of the embodiments will be described with reference to Figures 8 to 11. These each have one or more tubular sheaths fitted on the roll body 11 and secured thereto at each end, gas being forced into a space formed between the or each said tubular sheath and the outer periphery of the roll body 11, thereby imparting elasticity to the roll surface. The or each said tubular sheath is made of a material having flexibility but no gas permeability, such as natural or synthetic rubber or a synthetic resin or plastics material.

The embodiment of Figure 8 comprises the roll body 11, a single tubular sheath 16 mounted on the roll body 11, and bands 17 securing the tubular sheath 16 to the roll body 11 at each end thereof. The bands 17 may be replaced by adhesive or adhesive tapes. Air is forced into the space formed between the tubular sheath 16 and the roll body 11 through the gas supply passages 13 which are formed both axially and radially in the roll body 11. The tubular sheath 16 is provided on its inner wall with annular ribs 21 which serve as seals two divide the abovementioned space into a plurality of compartments.

This arrangement serves to prevent the tubular sheath 16 from bulging to a barrel-like configuration when gas is blown into the space.

The embodiment of Figure 9 comprises the roll body 11, a plurality of tubular sheaths 16' which are relatively narrow (i.e. of short axial length) mounted on the roll body 11, seal means, such as bands 17, for securing the tubular sheaths 16' at each end thereof and making gas-tight the spaces between the roll body 11 and the tubular sheaths 16'. Gas is blown into the spaces through gas supply passage 13 formed in the roll body 11. If the distance between the inflated portions of the tubular sheaths 16' is too wide for smooth feeding of the corrugated fibreboard web, separate elastic members (not shown) may be mounted between the adjacent tubular sheaths 16' to fill up the valleys between said sheaths 16'.

The embodiment of Figure 10 comprises roll body 11, a tubular sheath 16 mounted on the roll body 11, clamping bands 17forsecuring said tubular sheath 16 to the roll body 11 at each end thereof, and seal means comprising a plurality of strings 18 annularly wound around the tubular sheath 16 at suitable spacings to separate the space formed between the tubular sheath 16 and the roll body 11 into a plurality of gas-tight sections. The embodiment of Figure 10 is similar to that of Figure 9 except that a single tubular sheath 16 is used and that the strings 18 serve as seal means instead ofthewider bands 17 in Figure 9.

The embodiment of Figure 11 is almost the same as that of Figure 10, but differs thereafter in that a single string 18 is spirally wound around the tubular sheath 16.

In the embodiments of Figures 8 to 11, too, gas supply passages 13 in the roll body, a rotary joint for connecting a gas supply hose with the gas supply passages 13, and a gas supply portforforcing gas directly into each section (instead of the gas supply passage and rotary joint) may be provided as already described with reference to various of the preceding embodiments.

In the embodiments of Figures 8 to 11, a stop valve or the like may be provided for each section of the spece between the roll body 11 and the tubular sheath or sheaths to prevent leakage of gas from any damaged portion of the tubular sheath or sheaths.

Athird group of embodiments is illustrated by Figure 12. In this group, a tubular sheath of a synthetic resin or plastics material having a multiplicity of air bubbles or cells on or in it is mounted on the roll body 11, In this group, therefore, the tubular sheath has an elasticity in itself.

The embodiment of Figure 12 comprises roll body 11 and a tubular sheath 19 having a multiplicity of independent air bubbles or cells 20 on it and mounted on the roll body 11 to enclose its outer periphery and secured to the roll body 11 at its ends by means of respective bands, strings, tapes or the like.

This type of tubular sheath may be replaced with a porous sheath having a multiplicity of air bubbles or cells in it like a sponge.

A fourth group of the embodiments is illustrated in Figures 13 to 17. They each have a roll body 11 whose outer periphery is enclosed by at least one elastic member having intrinsic elasticity.

The embodiment of Figure 13 comprises roll body 11 and two elastic members 22 in the form of cords wound spirally around the roll body 11. The elastic members 22 may be fastened to the roll body 11 by means of adhesive, adhesive tapes or any other suitable fastening. Preferably, the roll body 11 should be provided with spiral grooves 15 so as to partially receive the elastic members 22. This assures stable location of the elastic members 22 on the roll body 11. In the embodiment of Figure 13, two elastic members 22 are wound spirally in the opposite directions, starting from the roll centre, this arrangement serving positively to prevent the corrugated fibreboard web from running out of true.

The embodiment of Figure 14 is substantially similar to that of Figure 13 but differs therefrom in that a single elastic member 22 is spirally wound around the body 11 in one direction. Even though the roll speed may be high or the roll may be narrow, the fibreboard web will not run out of true, although the elastic member 22 is wound in a single direction.

In the embodiment of Figure 15, a plurality of annular elastic members 22 is mounted in annular grooves 13 formed in the outer periphery of the roll body 11, at suitable spacings.

In the embodiment of Figure 16, a plurality of elastic members 22 is mounted on the roll body 11 so as to extend parallel to the axis of the roll body and to one another. Grooves 15 are formed in the outer periphery of the roll body 11 for stable location of the elastic members 22.

The embodiment of Figure 17 differs from that of Figure 16 only in that the elastic members 22 are mounted on the roll body 11 so as to extend at an angle with respect to the axis of the roll body 11.

In any of the embodiments of Figures 13 to 17, the distance between the elastic members 22 or the helices thereof should not be so large as to interfere with smooth feeding or passage of the corrugated fibreboard web. In any of the embodiments, the elastic members may be fastened by adhesives, adhesive tapes or any other suitable fasteners.

In the embodiments of Figures 13 to 17, the elastic member 22 is in the form of a cord or strin having a circular or rectangular cross-section. Therefore, this group of embodiments is advantageous in that it employs elastic members of greater elasticity, yet uses a lesser amount of resilient material than the preceding embodiments.

The embodiment of Figure 18 comprises the roll body 11 and a tubular elastic member 23 mounted on the roll body 11 to enclose its outer periphery and fastened to the roll body 11 by means of bands, adhesive tapes or other means. Since the elastic member is in the form of a sheath, this embodiment is advantageous in that the contact with the web will be over a larger area.

If it is to be secured to the roll body 11 by means of adhesive, the elastic tubular member 23 may advantageously be provided with an adhesive layer 24 on its inner surface as illustrated in Figure 19.

The roll of Figure 20 is a modification of the embodiment of Figure 18 having the tubular elastic member 23 provided with a lining layer 25 on its outer surface to increase strength, abrasion resistance and ease of cleaning off any foreign matter which might cling to its surface. Ease of cleaning is particularly importantforthe rider roll which is prone to becoming soiled with splashed glue. The lining layer 25 is required particularly if the tubular elastic member 23 is of foamed plastics material.

The tube 12, tubular sheaths 16, 16', 19, elastic member 22 and tubular elastic member 23 may be made of natural rubber, or synthetic rubber such as ethylene vinyl acetate (EVA), butadiene rubber (BR), styrene butadiene rubber (N BR), or a synthetic resin or plastics material such as urethane or polyethylene, or any combination thereof. Preferably, they should have a good formability, processability, elasticity, heat resistance, ease of cleaning matter, and abrasion resistance. They may comprise either a single layer or two or more layers made of the same or different materials. They may also be reinforced by interweaving with cloth or the like in the layer or between the layers to increase the strength.Particularly the tubular sheaths 16 and 16' may be reinforced, e.g. by interweaving, with steel wires, to maintain them in good shape for normal feeding of the web.

The lining 25 may be of synthetic resin such as polyester, nylon and silicon resin.

Natural rubber has a greater elasticity than synthetic rubber because it is of lower hardness, but synthetic rubber is better than natural rubber in abrasion resistance and heat resistance.

The advantages and effects of the roll in accordance with the present invention are as follows.

Firstly, if it is used as a rider roll in the glueing section of a corrugating machine wherein the singlefaced corrugated fibreboard web S passes between the glue roll 3 and the rider roll 5 (Figure 1) for application of glue to the peaks of its corrugations, the roll 1 contacts the web not on a line but over a surface because of its elasticity so that the pressure applied to a unit area of the web Swill be less than with conventional steel rolls. Since the roll 1 has some elasticity on its outer periphery, it can absorb shock, unevenness of the liner side of the web and variations in the thickness of the web. This advantage is particularly marked with the embodiments using gas to impart elasticity to the roll so long as the gas pressure is suitable.The nip pressure can be easily adjusted by adjusting the pressure of the gas filled into the tubes, which pressure can be indicated on a meter.

In contrast to conventional steel rider rolls, which cannot absorb such changes or shocks, the roll according to this invention ensures that the web is pressed by the roll with a pressure sufficient to assure application of an appropriate amount of glue but not so excessive as to deform the corrugations.

This helps to minimize the possibility of producing defective webs, such as corrugation-deformed webs, poorly glued webs, or warped or deformed webs, and increases useful production. Further, adjustment of clearances between the rolls according to the change of material, flute type, and so on is not needed any more. This is particularly true for the embodiments using gas to impart elasticity to the rolls.

If a roll in accordance with the present invention is used as a weight roll in the heating section of a corrugating machine, too, the roll 1 contacts the web not on a line but over a surface so that the pressure applied per unit area of the web will be much less than with a conventional steel roll even though the total nip pressure remains the same. This makes it possible to increase the pressure on the corrugated fibreboard web without the fear of deforming the corrugations, resulting in better heat transfer efficiency, higher machine speed and increased production per unit time. Further, because the roll according to this invention can absorb any irregularities on the surface of the cotton belt, at laced joints or any other bulging portions, it eliminates the need for readjusting the position of the weight rolls according to change in the material, flute type, and soon.

Simiiarly, if rolls according to this invention are used as feed rolls upstream of a rotary cutter D (Figure 2), the web is contacted by the upper and lower rolls over a surface, not on a line, so that the possibility of causing deformation of the corrugations is considerably reduced. Since the contact area between the roll and the web increases, larger frictional force for feeding the web can be obtained.

This decreases the nip force required for the rolls, thus decreasing the possibility of deforming the corrugations. This is particularly true when a material having a large frictional resistance is selected as the material with which the roll body is covered.

The roll in accordance with the present invention may be of an axial length greater than the entire width of the web or may be a shorter roll registering with only part of the web width, such as an auxiliary feed roll.

Although preferred embodiments have been described, it is to be understood that changes and variations may be made within the scope of the invention as defined by the following claims.

Claims (31)

1. A roll for use in a corrugated fibreboard production and processing machine characterised in that said roll has elasticity at its outer periphery.

2. A roll as claimed in claim 1 comprising a roll body and at least one flexible but not permeable tube disposed on the roll body so as at least partially to cover the surface of the roll, said tube being adapted to be inflated by forcing gas therein.

3. A roll as claimed in claim 2 wherein said tube is spirally wound around the roll body.

4. A roll as claimed in claim 2 wherein a plurality of said tubes are annularly disposed on the roll body.

5. A roll as claimed in claim 2 wherein a plurality of said tubes are disposed on the roll body parallel to the axis of the roll body.

6. A roll as claimed in claim 2 wherein a plurality of said tubes are disposed on the roll body so as to extend at an angle with respect to the axis of the roll body.

7. A roll as claimed in any of claims 2 to 6 wherein the roll body is formed with at least one groove in its outer surface partially to receive said tube or tubes.

8. A roll as claimed in any of claims 2 to 7 wherein each of said tubes has gas supply port means through which gas is forced therein.

9. A roll as claimed in any of claims 2 to 7 wherein the roll body is provided with a gas supply passage and a connecting means for connecting said passage with the tube or each of said tubes.

10. A roll as claimed in claim 2, wherein said tube is made of natural or synthetic rubber or synthetic resin or a combination thereof and is constructed of at least one layer.

11. A roll as claimed in claim 10 wherein said tube is reinforced by interweaving the material with cloth or the like.

12. A roll as claimed in claim 1 comprising a roll body and at least one flexible but not permeable tubular sheath mounted on the roll body and fastened thereto at each end thereof, said tubular sheath being adapted to be inflated by forcing gas into a space between said tubular sheath and the roll body.

13. A roll as claimed in claim 12, further comprising seal means for dividing said space into a plurality of compartments.

14. A roll as claimed in claim 13 wherein said seal means comprise a plurality of annular ribs integrally formed on the inner surface of said tubular sheet at a suitable spacing therebetween.

15. A roll as claimed in claim 13 wherein said seal means comprise a-plurality of bands or strings disposed annularly and with spacing therebetween, around said tubular sheath.

16. A roll as claimed in claim 13 wherein said seal means comprise at least one band or string spirally wound around said tubular sheet.

17. A roll as claimed in any of claims 12to 16 wherein said tubular sheet has gas supply port means from which gas is forced therein.

18. A roll as claimed in any of claims 12 to 16 wherein the roll body is provided with an axial gas supply passage and a plurality of radial passages communicating with said axial passage for forcing gas into each of said compartments.

19. A roll as claimed in claim 12, wherein said tubular sheath is made of natural or synthetic rubber or synthetic resin or a combination thereof and comprises at least one layer.

20. A roll as claimed in claim 19 wherein said tubular sheath is reinforced by interweaving the material with cloth, wire or the like.

21. A roll as claimed in claim 1 comprising a roll body and a tubular sheath mounted on the roll body to cover its outer surface, said tubular sheath being made of synthetic resin and having air bubble cells thereon or therein.

22. A roll as claimed in claim 1 comprising a roll body and at least one elastic member in the form of a cord wound around the roll body so as to cover at least part of the surface thereof.

23. A roll as claimed in claim 22 wherein said roll body is formed with at least one groove in its outer surface partially to receive said elastic member.

24. A roll as claimed in claim 22 wherein said elastic member is made of natural or synthetic rubber or synthetic resin or a combination thereof and comprises at least one layer.

25. A roll as claimed in claim 2 comprising a roll body and at least one elastic tubular sheath mounted on the roll body so as to cover at least part of the surface thereof.

26. A roll as claimed in claim 25 wherein said elastic tubular sheath has its outer surface provided with a lining.

27. A roll as claimed in claim 25 wherein said elastic tubular sheath is made of natural or synthetic rubber or synthetic resin or a combination thereof and comprises at least one layer.

28. A roll as claimed in claim 27 wherein said elastic tubular sheath is reinforced by interweaving the material with cloth or the like.

29. A roll for use in a corrugated fibreboard production and processing machine substantially as hereinbefore described with reference to and as illustrated in any of Figures 2 to 20 of the accompanying drawings.

30. A corrugated fibreboard production and processing machine incorporating at least one roll as claimed in any of claims 1 to 29.

31. A corrugated fibreboard production and processing machine substantially as hereinbefore described with reference to and as illustrated in Figure 1 and/or Figure 2 of the accompanying drawings.