NL2028395B1

NL2028395B1 - Building element comprising shaped netting and a machine therefor

Info

Publication number: NL2028395B1
Application number: NL2028395A
Authority: NL
Inventors: Bernardus Haverkotte Johannes; Groeneweg Jan; Wasse Jan
Original assignee: Huizenkluis B V
Priority date: 2021-06-04
Filing date: 2021-06-04
Publication date: 2022-12-15

Abstract

A building element is provided comprising a polymer foam material body and a reinforcement netting afﬁxed to a first side of the body, the reinforcement netting being shaped in a ﬁrst multitude of netting shapes having a ﬁrst netting level and a second multitude of netting shapes having a second netting level. The first side of the body has a ﬁrst multitude of body shapes having a ﬁrst body level and a second multitude of body shapes having a second body level; the netting is affixed to the body by the netting shapes being affixed to the ﬁrst multitude of body shapes. The first multitude of body shapes may be at locations Where the polymer foam material body is thinner than at locations of the second multitude of body shapes. This provides a rigid building element, providing insulation and anchoring for further layers to be attached to the building element.

Description

P130065NL00 Title: Building element comprising shaped netting and a machine therefor

TECHNICAL FIELD An aspect and embodiments thereof relate to a building element comprising a building panel and a shaped netting. Another aspect and embodiments thereof relate to a machine for shaping a netting for the building element.

BACKGROUND Building panels having netting attached thereto are known from EP1759071B1. This patent discloses a flat panel with netting embedded in the foam material.

SUMMARY It is preferred to provide a building element having improved rigidity. A building element is provided comprising a polymer foam material body and a reinforcement netting affixed to a first side of the body, the reinforcement netting being shaped in a first multitude of netting shapes having a first netting level and a second multitude of netting shapes having a second netting level. In this building element, the first side of the body is shaped in a first multitude of body shapes having a first body level and a second multitude of body shapes having a second body level; and the netting is affixed to the body by at least part of the first multitude of netting shapes being affixed to at least part of the first multitude of body shapes. The first multitude of body shapes may be at locations where the polymer foam material body is thinner than at locations of the second multitude of body shapes. This provides a rigid building element, providing insulation and anchoring for further layers to be attached to the building element, like concrete or plaster material. A first difference between the first body level and the second body level is different from a second difference between the first netting level and the second netting level. This allows for connecting one of the first plurality of shapes of the netting to the foam body and the other not. This means that space may be provided between the second plurality of shapes of the netting and the foam body. In this space, at least one of plaster material may be provided for strength or conduits for power or fluid material may be provided - or other elements that may be required or desirable in a building.

The netting may be affixed to the body by at least part of the netting being embedded in the body. This provides improved attachment of the netting to the body.

The netting is affixed to the body by means of a binding agent.

This may be established by embedding the netting - in which case the foam base material is the binding material - or by applying a glue or other type of cement to the surface of the foam body to attach the netting to the foam body. These options may also be combined.

The binding agent comprises a binding agent material similar to the polymer foam material of the body. For example, the foam may comprise polyurethane foam and the binding agent may be polyurethane glue.

The body shapes may be shaped in a single dimension. Basically, this means that the body shapes are provided as longitudinal element.

The body shapes may have a periodic structure. This enhances the ease of manufacturing and the ease of using the building element in design and construction of buildings.

The netting shapes may be shaped in a single dimension. Basically, this means that the netting shapes are provided as longitudinal element.

The netting shapes may have a periodic structure. This enhances the ease of manufacturing and the ease of using the building element in design and construction of buildings.

The netting may comprise a first set of parallel wires and a second set of parallel wires. Such netting is generally well available and may be processed without complications or significant complications.

The wires of the first set may be perpendicular to the second set. Such netting provides structural rigidity in two directions.

The shapes may be provided by only shaping the first set of parallel wires. This may allow for convenient processing of the netting, as well as rigidity, as only one set of wires is to be shaped.

The building element may further comprise a granulate mineral material like sand provided on the first side of the body in a blanket fashion. This may provide additional anchoring of layer of cement, plaster or other material.

To address issues with existing machines, a device for shaping a netting is provided. The device comprises a first shaping cylinder comprising a multitude of first protrusions radially extending from an outer wall of the cylinder and annularly equidistantly distributed over the outer wall and a second shaping cylinder comprising a multitude second of protrusions radially extending from an outer wall of the cylinder and annularly equidistantly distributed over the outer wall. The device further comprises a first drive unit for driving unit for driving at least one of the first shaping cylinder and the second shaping cylinder, a device frame arranged to support the first shaping cylinder and the second shaping cylinder in a rotating fashion such that first centreline of the first shaping cylinder 1s substantially parallel to the second shaping cylinder and such that the multitude of first protrusions is arranged to engage with the multitude second of protrusions and a biasing module arranged to apply a biasing force, preferably in a resilient way, to at least one of the first shaping cylinder and the second shaping cylinder such that the first shaping cylinder and the second shaping cylinder are biased towards one another.

In this device, the biasing module, the first protrusions and the second protrusions are arranged such that when netting is provided between the first shaping cylinder and the second shaping cylinder, the netting is force fitted between the first shaping cylinder and the second shaping cylinder at substantially each rotational position of the first shaping cylinder and the second shaping cylinder.

By providing the substantially continuous force fit - for example for at least 90%, at least 95% or at least 99% of the circumference of the shaping cylinders - the netting is kept at a stable position between the shaping cylinders and is unable to slip or otherwise move relative to the shaping cylinders during the shaping process.

This, in turn, allows for a controlled continuous feed of the netting by action of the shaping cylinders alone, without the need of further driving means for feeding the netting through the process.

The protrusions may have an elongate shape.

This allows for forming of elongate deformations in the netting, for example wave-shaped.

The first protrusions may be provided substantially parallel to a first centreline of the first shaping cylinder and the second protrusions may be provided substantially parallel to a second centreline of the second shaping cylinder.

This allows for waves perpendicular to the length of the netting.

The first protrusions may be provided under a first angle relative to a first centreline of the first shaping cylinder and the second protrusions may be provided under a second angle relative to a second centreline of the second shaping cylinder, wherein the first angle is preferably substantially the same as the second angle.

With the first angle substantially the same as the second angle, the first protrusions and the second protrusions are allowed to mesh like gears, as with other implementations and the general concept. For certain use of the netting, providing waves under an angle may have advantages.

The protrusions may have a trapezoid shape, wherein the longer parallel sides are provided at the outer wall of the first shaping cylinder and 5 the outer wall of the second shaping cylinder and the shorter parallel side is provided at a distance from at the outer wall of the first shaping cylinder and the outer wall of the second shaping cylinder. With such shapes, trapezoid shaped waves may be provided in the netting. The angles in the waves are obtuse, which means less stress in the netting compared to square angles, which may lead to fatigue and breaking of the netting. Curved waves may provide even more benefits at such points and the protrusions may be shaped to provide curved waves. However, trapezoid shaped protrusions are preferred as that shape provides improved meshing as indicated.

The centreline of the first shaping cylinder may be substantially horizontally placed and the second shaping cylinder may be provided above the first shaping cylinder. This allows for stable feed of the netting to be shaped, in a horizontal orientation.

The distance between the first centreline and the second centreline may be varied. With the first shaping cylinder and the second shaping cylinder being arranged in the frame such that at least one of the shaping cylinder is movable relative to the frame and relative to the other shaping cylinder, netting with different thickness may be processed, while ensuring the force fitting of the netting between the shaping cylinders. For example, the biasing module may be further arranged to move the first centreline relative to the second centreline.

The biasing force provided by the biasing module may be adjustable. This allows for optimising setting for different types of netting for example with different materials, different shapes, different weaves and different thicknesses to ensure optimal force fitting.

The biasing module may comprise at least one of a hydraulic cylinder, a pneumatic cylinder and a resilient biasing element. in particular a hydraulic cylinder and a pneumatic cylinder allow for adjustment of the distance between the centrelines of the shaping cylinders. And the pneumatic cylinders and (passive) resilient biasing elements allow for variations of the distance between the centrelines of the shaping cylinders, under a biasing force. The latter may improve the force fitting principle, without damage or in any case by reducing damage to the netting.

The first drive unit may be arranged to drive the first shaping cylinder and the device may further compris a second drive unit arranged to drive the second shaping cylinder. This allows for independent driving of each cylinder - although the drive units may be synchronised to rotate at generally the same rotational speed to allow the protrusions to mesh or to engage in a meshing action.

More in particular, the first drive unit may comprises a first electromotor and the second drive unit comprises a second electromotor and the device further comprising an electronic power supply unit. The electronic power supply unit may be arranged to, provide a first electrical power supply signal to the first electromotor, provide a second electrical power supply signal to the second electromotor; and synchronise a first waveform of the first electrical power supply signal to a second waveform of the second electrical power supply signal.

The electromotor may be a stepper motor, but it may also be a brushless electromotor or another AC electromotor of which the rotational speed may be controlled by means of controlling a frequency of a power signal provided to the electromotor.

The device according may further comprise a mechanical coupling means for coupling the first drive unit, the first shaping cylinder and the second shaping cylinder such that the first driving unit drives the first shaping cylinder and the second shaping cylinder at substantially the same annular speed, in opposite directions. Whereas a mechanical coupling may, in certain scenarios be more reliable, it may introduce slack between the shaping cylinders.

BRIEF DESCRIPTION OF THE DRAWINGS The technology discussed above and further details thereof will now be discussed in further detail below in conjunction with drawings. In the drawings: Figure 1 A shows a first view of a machine for shaping netting; Figure 1 B shows a second view of the machine for shaping netting; Figure 2 shows rollers as a detail of the machine for shaping netting; Figure 3 shows a shaped netting; and Figure 4 shows a building module as a building element.

DETAILED DESCRIPTION Figure 1 A and Figure 1 B show a machine 100 for shaping a netting. The machine 100 comprises a frame 110 comprising a base frame part 112, a first roller pillar 114, a second roller pillar 116 and two real holders 118. The real holders 118 are arranged for holding a reel 172 arranged for holding a netting. Between the first roller pillar 114 and the second roller pillar 116, a first roller 122 as a first shaping cylinder and a second roller 124 as a second shaping cylinder are provided.

Figure 2 shows the first roller 122 and the second roller 124 in further detail. The first roller 122 comprises a first cylindrical body 212 on which a first multitude of first protrusions 214 are provided. The second roller 124 comprises a second cylindrical body 222 on which a second multitude of second protrusions 224 are provided.

The first protrusions 214 are provided on the first cylindrical body 212 substantially equidistantly on the circumferential outer wall of the first cylindrical body. Preferably, the first protrusions 214 are elongate protrusions, provided over at least 50%, preferably at least 75% and more preferably at least 90% of the length of the first cylindrical body 212. Preferably, the first protrusions 214 are provided on the first cylindrical body 212 such that the longitudinal orientation of the first protrusions 214 is parallel to the centreline of the first cylindrical body 212. Alternatively, the first protrusions 214 are provided under an angle relative to the centreline.

The second protrusions 224 are provided on the second cylindrical body 222 substantially equidistantly on the circumferential outer wall of the second cylindrical body. Preferably, the second protrusions 224 are elongate protrusions, provided over at least 50%, preferably at least 75% and more preferably at least 90% of the length of the second cylindrical body 222. Preferably, the second protrusions 224 are provided on the second cylindrical body 222 such that the longitudinal orientation of the second protrusions 224 is parallel to the centreline of the second cylindrical body

222. Alternatively, the second protrusions 224 are provided under an angle relative to the centreline, preferably substantially the same angle as the first protrusion relative to the centreline of the first cylindrical body 212.

The first protrusions 214 and the second protrusions 224 are in Figure 2 shown as being separate monolithic elements. Alternatively, they may be manufactured as being part of a larger monolithic element including the first cylindrical body 212 and the second cylindrical body 222, respectively. The first protrusions 214 and the second protrusions 224 may also be provided as each comprising multiple monolithic elements.

As shown in Figure 2, the first protrusions 214 and the second protrusions 224 have a trapezoid shape, with the larger parallel side, the base, being connected to the outer surfaces of the first cylindrical body 212 and the second cylindrical body 222, respectively.

The smaller parallel side, the top, is provided away from the surfaces of the cylindrical bodies, further away from the centreline of the cylindrical bodies than the base.

Preferably, the distance between the bases of the first protrusions 214 and the second protrusions 224 is substantially the same as the length of the tops of the trapezoid shapes.

Alternatively, the distance between the bases of the first protrusions 214 and the second protrusions 224 is larger or smaller than the length of the tops of the trapezoid shapes.

The first protrusions 214 and the second protrusions 224 preferably all have substantially the same shape.

The angels of the trapezoid shapes as shown by Figure 2 are selected such that with a netting, for example a wire gauze or other sheet-like material with an open or a closed structure provided between the first roller 122 and the second roller 124, the netting is force-fitter between the first roller 122 and the second roller 124 at substantially every position of the first roller 122 and the second roller 124, preferably at every position of the first roller 122 and the second roller 124. To enable the force fitting of multiple types of netting or other sheet-like material, the first roller 122 is suspended on the first roller pillar 114 by means of a first hydraulic cylinder 152 as a first biasing element and on the second roller pillar 116 by means of a second hydraulic cylinder 154 as a second biasing element.

The first roller 122 is, by means of the hydraulic cylinders, movable relative to the second roller 124 such that the distance between the centrelines of the rollers may be varied.

Figure 1 A and Figure 1 B show the first roller 122 as the upper roller that is movable, but additionally or alternatively, the lower, second roller 124 is movable.

Furthermore, by varying hydraulic pressure - pressure of hydraulic fluid - in the hydraulic cylinders, a biasing force exerted by the first roller 122 on a netting and the second roller 124 may be varied.

Preferably, at least one of the hydraulic pressure provided and the position of the first roller 122 relative to the second roller 124 depends on the thickness of the netting to be shaped. Preferably, the distance between the first roller 122 and the second roller 124, the protrusions taken into account, is substantially the same or slightly less than the thickness of the netting to be shaped. In that way, no clearance or slack is present and the netting is drawn from the reel 172 with generally constantly a force being applied to the netting on the reel 172. Preferably, the netting is drawn from the reel at a substantially constant speed and a substantially constant force.

The machine 100 may be provided with an input module like buttons or a touch screen to provide a thickness of the netting and a control circuit to retrieve data from a memory in response to the input thickness and to adjust at least one of hydraulic pressure and position of pistons in the hydraulic cylinders in accordance with the retrieved data.

Additionally or alternatively to the hydraulic cylinders, pneumatic cylinders may be used, using compressed gases rather than a dense compressed fluid like oil or water. An advantage is that pneumatic cylinders provide a certain resilience as the gas in the cylinders is compressible, in any case far more compressible than liquid in hydraulic cylinders. To enhance resilience of the system, i.e. resilience of a connection the cylinders and at least one of the rollers, resilient biasing elements like helical springs, other springs, rubber or other elastomer elements, other or a combination thereof, may be provided between the cylinders and the rollers, between the cylinders and the frame 110. Hence, a biasing module may be provided with at least one of a hydraulic cylinder, a pneumatic cylinder and a resilient biasing element.

The first roller 122 is connected to a first driving module 130 as a drive unit comprising a first electromotor 132 and a first drive train 134. The first electromotor 132 is arranged to rotate the first roller 122 via the first drive train 134. The first electromotor 132 may be a stepper motor, a bushed or brushless motor, a synchronous or asynchronous machine or any other type of electromotor. Preferably, the rotational speed of the first electromotor 132 may be controlled by controlling a frequency of a waveform of an electrical power signal provided to the first electromotor 132 for powering first electromotor 132.

The second roller 124 is connected to a second driving module 140 as a drive unit comprising a second electromotor 142 and a second drive train 144. The second electromotor 142 is arranged to rotate the second roller 124 via the second drive train 144. The second electromotor 142 may be a stepper motor, a bushed or brushless motor, a synchronous or asynchronous machine or any other type of electromotor. Preferably, the rotational speed of the second electromotor 142 may be controlled by controlling a frequency of a waveform of an electrical power signal provided to the second electromotor 142 for powering second electromotor 142.

The first electromotor 132 and the second electromotor 142 are preferably provided with a first electrical power signal and a second electrical power signal, respectively, which have substantially and preferably exactly the same frequency. Preferably, the first electrical power signal and the second electrical power signal are provided by an electrical control module 180 that is arranged to control frequency and, optionally, at least one of current, voltage and phase of the electrical power signals provided. In this way, the first roller 122 and the second roller 124 may be rotated at substantially and preferably exactly the same speed to shape a netting.

Alternatively, the machine 100 is provided with only one electromotor and the first roller 122 and the second roller are driven by one and the same electromotor and connected via a mechanical coupling module like a belt, a chain or a set of one or more gears.

With the machine 100 as shown by Figure 1 A and Figure 1 B, the driving modules are provided on one side of the machine 100 and on one and the same side in particular. With the first roller 122 being movable, for example in vertical slots in the first pillar 114 and the second pillar 116, this may result in imbalances in the first roller 122. To compensate for the weight of the first driving unit 130, a counterweight module 162 may be provided at the other side of the first roller, preferably coupled to the first roller 122.

Netting to be shaped may be provided on the reel 172 and be provided to the first roller 122 and the second roller 124 via a feeder plate

162. The feeder plate 162 may also be used to align the netting with the first roller 122 and the second roller 124. To that purpose, the feeder plate 162 may be provided with raised edges on either side of the feeder plate 162.

Figure 3 shows a shaped netting 300. The shaped netting 300 may shaped by the machine 100 or another machine. The shaped netting 300 comprises a first set of longitudinal wires 312 and a second set of transversal wires 314. The longitudinal wires 312 are provided substantially perpendicularly to the transversal wires 314. Alternatively, wires of two sets may be provided under an obtuse or acute angle relative to one another. Additionally, a further set of parallel wires may be provided, under any angle relative to the wires of the first set and the second set. In this way, hexagonal shapes, triangular shapes, other shapes or a combination thereof may be provided.

With the shaped netting 300 of Figure 3, only the longitudinal wires 312 are shaped in trapezoid shapes. The transversal wires 314 are straight. As a starting material, preferably a flat sheet of netting provided, which means that in the case depicted by Figure 3, means that the transversal wires are not shaped by the machine 100 or any other suitable machine. Additionally or additionally to the trapezoid shapes, also square, triangular, sinusoidal, sawtooth, other shapes or a combination thereof may be provided.

The longitudinal wires 312 and with that, the shaped netting 300 is shaped in shapes - trapezoids - having a first level - the lower level of valleys 324 - and a second level - the higher level of hills 322. The first level and the second level are defined as perpendicular relative to a plane defined by the length and the width of the shaped netting 300, so perpendicular to the transversal direction and transversal to the longitudinal direction.

By shaping the longitudinal wires 312 only, the shaped netting is shaped in a single dimension only, with, as indicated above, only the longitudinal shapes being shaped. Alternatively, also the transversal wires 314 may be shaped in the same levels - or different levels -, resulting in local peaks, rather than in longitudinal raised regions and longitudinal depressed regions parallel thereto in the shaped netting 300. Preferably, the hills 322 and the valleys 324 or other shapes are provided in a periodic fashion.

Figure 4 shows the shaped netting 300 affixed to a building panel 410, providing a building module 400 as a building element. The building panel 410 preferably predominantly comprises a rigid foam substance, like polyurethane or an equivalent substance like a polymer foam material, having a closed or open cell foam structure. Within the context of this description, a substance may comprise a single material or multiple materials. Like the shaped netting 300, also the building panel 410 1s shaped over the longitudinal direction, indicated by the arrow "L"; the surface of the building panel 410 is substantially straight over the transversal direction indicated by the arrow "T". The shape of the building panel 410 on the top side as a first side is substantially the same or at least similar or congruent to the shapes of the shaped netting 300.

With the building panel 410 as shown by Figure 4, the building panel 410 is shaped in trapezoid shapes, having a first level - the lower level of the upper surface - and a second level - the upper level of the top surface. In this embodiment, the difference between the first level of the top surface of the building panel 410 and the second level of the upper surface of the building panel 410 is smaller than the difference between the first level of the shaped netting 300 and the second level of the shaped netting 300. With the shaped netting 300 being at the valleys of the shaped netting 300 affixed to the building panel 410 at the valleys in the top surface of the building panel 410, this means that space 1s provided between the hills in the shaped netting 300 and the hills of the top surface of the building panel 410. The shaped netting 300 may be connected to the building panel 410 in various ways. The shaped netting 300 may be embedded in the substance of which at least most of the building panel 410 is made. This may be established while manufacturing the building panel 410, for example before or during curing of a foam forming substance. Alternatively or additionally, a binding agent may be provided on top a cured or almost cured building panel 410 and the shaped netting 300 may be affixed to the building panel 410 by means of the binding agent. The binding agent may comprise a substance that is the same as a substance comprised by the building panel 410; additionally or alternatively, the binding agent may comprise a different substance. At the top side of the building panel 410, a granulate mineral material, like sand (silicon dioxide), other, or a combination thereof may be provided. The granulate material may be affixed to the building panel 410 by means of a binding agent, which may be the same or a different binding agent as with which the shaped netter 300 is attached to the building panel

410. The granulate material may be provided on a part of the building panel 410 or in a blanket fashion, all over the top surface of the building panel

410. Optionally, the granulate material may be provided on other surfaces of the building panel 410. If the same binding agent is used as for affixing the shaped netting 300 to the building panel 410, the binding agent may be applied in a blanket fashion on the top surface of the building panel 410 prior to application of the shaped netting 300. After the binding agent has been applied in a blanket fashion, the shaped netting 300 is applied, followed by the granulate material.

After the building module 400 has been manufactured, it may be used as a building element for a wall, floor, ceiling or roof of a building like a house, warehouse, apartment building, factory, other, or a combination thereof.

Between the shaped netting 300 and the building panel 410, with the building module 400 as depicted between the hills of the shaped netting 300 and the hills of the building panel 410, wires, tubes and conduits for utility like electricity, combustible fluids like gas, water and other material or energy may be provided.

On the top side of the building module 400, concrete or another curable material may be provided, preferably after the conduits have been applied.

The granulate material may enhance the bonding between the curable material and the building module 400.

Claims

Conclusions

A building element comprising a polymer foam material body and a reinforcement net attached to a first side of the body, the reinforcement net being formed in a first plurality of net shapes including a first net level and a second plurality of net shapes including a second net level, wherein: the first side of the body is formed into a first plurality of body shapes including a first body level and a second plurality of body shapes including a second body level; and the net is attached to the body by at least a portion of the first plurality of net shapes attached to at least a portion of the first plurality of body shapes.

A building element according to claim 1, wherein a first difference between the first body level and the second body level is different from a second difference between the first net level and the second net level.

A building element according to claim 2, wherein the first difference is less than the second difference.

A building element according to any one of the preceding claims, wherein the net is attached to the body in that the net is at least partly enclosed by the body.

A building element according to any one of the preceding claims, wherein the net is attached to the body by means of a binding agent.

A building element according to claim 5, wherein the binding agent comprises a binding agent material comparable to the polymer foam material of the body.

A building element according to any one of the preceding claims, wherein the body shapes are formed in a single dimension.

A building element according to claim 7, wherein the body shapes have a repeating structure.

A building element according to any one of the preceding claims, wherein the body shapes have a trapezoidal shape.

A building element according to any one of the preceding claims, wherein the net shapes are formed in a single dimension.

A building element according to claim 7, wherein the net shapes have a repeating structure.

A building element according to any one of the preceding claims, wherein the net shapes have a trapezoidal shape.

A building element according to any one of the preceding claims, wherein the net comprises a first set of parallel wires and a second set of parallel wires.

A building element according to claim 13, wherein the threads of the first set are perpendicular to the threads of the second set.

A building element according to claim 13 or claim 14 when dependent on claim 10 or claim 11, wherein the shapes are provided by forming only the first set of parallel wires.

A building element according to any one of the preceding claims, further comprising a granular mineral material provided in a blanket-like manner on the first side of the body.

17. A netting apparatus, the apparatus comprising: a first forming cylinder including a plurality of first projections extending radially from an outer wall of the cylinder and equally spaced annularly on the outer wall; a second forming cylinder comprising a plurality of second projections extending radially from an outer wall of the cylinder and equally spaced annularly on the outer wall: a first drive unit for driving at least one of the first forming cylinder or the second forming cylinder; an apparatus frame arranged to rotatably support the first forming cylinder and the second forming cylinder so that the first axis of the first forming module is substantially parallel to the second forming cylinder and so that the plurality of first projections are directed to engage the plurality of second bulges; a biasing module configured to apply a biasing force to at least one of the first forming cylinder or the second forming cylinder so that the first forming cylinder and the second forming cylinder are biased toward each other; wherein the biasing module, the first protrusions and the second protrusions are arranged such that when the net is provided between the first forming cylinder and the second forming cylinder, the net is forcibly fitted between the first forming cylinder and the second forming cylinder at substantially any rotational position of the first forming cylinder and the second forming cylinder.

The device of claim 17, wherein the protrusions have an elongated shape.

An apparatus according to claim 18, wherein the first protrusions are provided substantially parallel to the first axis of the first forming cylinder and the second protrusions are provided substantially parallel to a second axis of the second forming cylinder.

The apparatus of claim 18, wherein the first protrusions are provided at a first angle relative to a first axis of the first forming cylinder and the second protrusions are provided at a second angle relative to a second axis of the second forming cylinder, the first angle is substantially the same as the second angle.

An apparatus according to any one of claims 17 to 20, wherein the protrusions have a trapezoidal shape, the longer parallel sides being provided near the outer wall of the first forming cylinder and the outer wall of the second forming cylinder and the shorter parallel sides being provided on a distance from the outer wall of the first forming cylinder and the outer wall of the second forming cylinder.

Apparatus according to any one of claims 17-21, wherein the axis of the first forming cylinder is disposed substantially horizontally and the second forming cylinder is provided above the first forming cylinder.

An apparatus according to any one of claims 17-22, wherein the distance between the first centerline and the second centerline is variable.

The apparatus of claim 23, wherein the biasing module is further configured to move the first axis relative to the second axis.

An apparatus according to any one of claims 17-24, wherein the biasing force provided by the biasing module is adjustable.

The apparatus of claim 25, wherein the biasing module comprises at least one of a hydraulic cylinder, a pneumatic cylinder, or a resilient biasing element.

An apparatus according to any one of claims 17-26, wherein the first drive unit is arranged to drive the first forming cylinder, the apparatus further comprising a second drive unit arranged to drive the second forming cylinder.

An apparatus according to claim 27, wherein the first drive unit comprises a first electric motor and the second drive unit comprises a second electric motor, the apparatus further comprising an electrical energy source unit arranged 18: providing a first electrical energy source signal to the first electric motor providing a second electrical energy source signal to the second electric motor; and synchronizing a first waveform of the first electrical energy source signal to the second electrical energy source signal.

An apparatus according to claim 27 or claim 28, wherein the electric motor is a stepping motor 1s.

An apparatus according to any one of claims 17 to 26, further comprising mechanical coupling means for coupling the first drive unit, the first forming cylinder and the second forming cylinder so that the first drive unit drives the first forming module and the second forming module at substantially the same angular velocity, in opposite directions.

Apparatus according to any one of claims 17 to 30, further comprising a reel holder for holding a reel of net and a power supply unit for receiving a net sheet from the reel and feeding the net to a space between the first forming cylinder and the first forming cylinder. second forming cylinder.