Patent Description:
Molds configured to produce tubular laminated objects, such as tanks and silos, on an outer circumference of the mold have previously been developed. Typically, such molds are of a fixed circumference. Alternatively, in order to facilitate variation of the circumference, such molds may comprise wall segments surrounding a central shaft. In the latter case, the wall segments jointly define the outer circumference of the mold. In a known example of a mold of this type, each of the plurality of wall segments is held by a telescopic beam provided with positioning holes and pins. The length of each telescopic beam is set manually by removing the pins, lifting the attached wall segment with a crane, shifting the telescopic beam to another positioning hole and returning the pin through that hole. A dimension of the outer circumference of the mold, in particular a circular diameter of the mold, is thus set by adjusting a radial distance between each wall segment and the central shaft one by one.

The adjustment of the outer circumference according to the state of the art is a time and labor intensive process that has to be performed in a hardly accessible place within the mold.

Publication <CIT> discloses an apparatus for manufacturing a resin tube. This apparatus comprises support means, a central shaft supported by the support means and extending therefrom, a pair of operating means supported by the central shaft at two separate positions, a plurality of rotatable forming rolls each supported by the operating means at both ends thereof in such a manner that the rotatable forming rolls are arranged circularly around the central shaft and that a cylindrical envelope formed by the rotatable forming rolls has a radius changeable by operation of the operating means, and a plurality of flexible link means each connected between one end of each rotatable forming roll and a driving means for simultaneously rotating the rotatable forming rolls in the same direction at any radius of the envelope. An extruded resin ribbon is supplied to these rotating forming rolls so that it is wound around the forming rolls with its side edges overlapped while being formed into a tubular body continuously being conveyed towards and withdrawn from the tip ends of the forming rolls.

In this prior art apparatus, the forming rolls are necessarily spaced apart and thus define a discontinuous hypothetical cylindrical surface onto which the resin ribbon is supplied. Further, this resin ribbon must cool or cure within the time interval between extrusion of the resin ribbon and withdrawal of the resin tube from the tip end of the forming rolls. These points impose limitations on the types of resin that can be used and on manufacturing throughput. For example, a resin of low viscosity may flow into the apparatus between the forming rolls and disturb operation.

A further disadvantage of the mechanism of this prior art apparatus is its large weight, especially due to its large conical cam body. Further, its conical cam bodies shift over the central shaft when adjusting the radius of the envelope defined by the rotatable forming rolls of the apparatus, which causes the conical cam bodies to protrude beyond the envelope in the direction of the central shaft. These disadvantages make this prior art system unusable to produce tanks and silos of conventional dimensions.

Publication<CIT> discloses two incompatible alternatives of a mold. In the first alternative, cylindrically shaped segments can be moved inwardly or outwardly at the same time, which however necessarily causes slits between the segments in the outer position of the segments that have to be covered by film. The second alternative is presented to overcome this problem, in which segments are not moved simultaneously but separately in time. In this second alternative, it is possible to prevent the slits between the segments in the outer position of the segments and even render the foil obsolete by implementing the segments with slanted or stepped sides so that these can overlap in said outer position. However, such segments have to be moved in the correct order. This prior art arrangement prevents the segments from being moved simultaneously as these would block each other.

Publication <CIT> discloses cylindrical tanks as well as a method of and an apparatus for forming such tanks from reinforces plastic material. Each cylindrical section is formed of two thicknesses of resin impregnated fabric which have been successively wound over a mandrel, the thicknesses being vertically displaced to permit overlapping at the joints between sections. As each section is completed, the mandrel is reduced in diameter and the section is raised vertically. The mandrel comprises adjacent panels normally bolted together via flanges which are parallel to the panels so that the panels can be dismantled towards the inside of the mandrel. Panels of the mandrel must be unbolted to allow reduction of the diameter of the mandrel.

Publication <CIT> discloses a process involving the steps of forming a tank end cap on a mandrel and thereafter supporting the end cap in space by means of a dead-center mechanism mounted to the floor and laying up a resin-rich wall layer of chopped strand and resin in joined relation to the end cap, and curing the wall partially; then forming over the outer surface of the wall a hollow shell structure which comprises a combination of woven roving and filament wound layers superimposed and saturated with wet resin. Then completely curing the composite wall to produce a monolithic structure.

It is therefore an objective of the invention to overcome or at least reduce the above disadvantages. This is achieved through the invention by providing a mold configured to produce tubular laminated objects, such as tanks and silos, on an outer circumference of the mold, wherein the mold comprises:.

Because the actuator is configured to adjust a radial distance of each of the plurality of wall segments relative to the central shaft simultaneously, the dimension of the outer circumference of the mold may be set in one operation. The time required to change from one dimension of the outer circumference (for example, a diameter of <NUM>) to another (for example, a diameter of <NUM>) is reduced. Moreover, said time is negligible with respect to the production time for a typical tank or silo. As an example, the time required for adjustment of the outer circumference of the mold according to the invention is about <NUM> minutes or less, contrasting with typically <NUM> hours or more required for adjusting circumference of state-of-the-art molds or for exchanging a mold in a production facility for another mold with a different diameter. Furthermore, the mold according to the invention provides greater flexibility in setting the circumference of the mold to numerous intermediate diameters, thus reducing the number of molds required in a production facility which otherwise would require large amounts of space. The mold according to the invention further enables improved fine adjustment of the outer circumference of the mold.

Further, the mold according to the invention has the advantage that a separate release mechanism for detaching a produced tubular laminated object from the mold is redundant and may be absent, thereby resulting in a simple and reliable mold. The actuator can decrease the dimension of the outer circumference of the mold by simultaneously reducing the radial distance of each of the plurality of wall segments relative to the central shaft and thereby release a produced tubular laminated object from the mold. In any embodiment of the invention, the wall segments can be shaped as panels, i.e. forming wall panels.

In the context of the present invention, the term 'radial' refers to a direction orthogonal to the axial direction defined by the orientation of the central shaft.

Though the outer circumference may have a cylindrical shape, which is a conventional shape for tanks and silo's, the mold of the present invention also permits other cross-sectional shapes, such as oval, egg-shaped and polygonal. Hence, the term 'tubular' must not be understood to be limited to cylindrical.

The adjustable connectors can be configured to remain within the confines of the outer circumference of the mold as defined by the plurality of wall segments during adjustment of the outer circumference, in particular when the adjustable connectors comprise mechanical linkages and/or articulated systems of rods as described below.

The actuator preferably comprises one or more than one hydraulic cylinder. Alternatively, one or more than one screw spindle can be employed. Although it is conceivable that the actuator, for example as a plurality of hydraulic cylinders and / or screw spindles, may define the plurality of adjustable connectors between the wall segments and the central shaft, the actuator is preferably configured to actuate the adjustable connectors. For example, the actuator may be configured to act in the radial direction to directly adjust the radial distance of each of the plurality of wall segments relative to the central shaft, or in the axial direction in which case the plurality of adjustable connectors may be configured to convert the action of the actuator in the axial direction into actuation in the radial direction.

Preferably, each adjustable connector is configured to maintain the associated wall segment substantially parallel to the axial direction. For example, each adjustable connector may comprise one or more than one hydraulic cylinder and / or mechanical linkage configured to hold the associated wall segment parallel to the axial direction at each radial distance of the associated wall segment relative to the central shaft.

Further it is preferred that one or more than one common carrier is connected to the mechanical linkages of the plurality of adjustable connectors and the actuator is configured to adjust a position of the one or more than one common carrier to thereby simultaneously actuate the mechanical linkages and set the dimension of the outer circumference of the mold. This has the advantage of improved simultaneous control of all wall segments.

Preferably, the position of the one or more than one common carrier is adjustable in the axial direction and each mechanical linkage is configured to convert adjustment of the position of the one or more than one common carrier into adjustment of the radial distance of the associated wall segment relative to the central shaft. This arrangement advantageously redirects and distributes action forces of the actuator in the axial direction for simultaneous adjustment of the radial distance of each of the plurality of wall segments, whereby the outer circumference of the mold is set.

Preferably, the one or more than one common carrier surrounds and is movable along the central shaft. The actuator may be configured to move the one or more than one common carrier along the central shaft. At least one of the one of more than one common carrier may comprise at least one roller and the central shaft may comprise at least one support surface configured to support the at least one roller. This arrangement reduces friction and prevents undesired deformations in the outer circumference of the mold. Alternatively, sliders may be employed instead of rollers.

Each mechanical linkage comprises one or more than one articulated system of rods configured to couple the associated wall segment to the central shaft. The term rod includes rails, bars and beams, for example comprising a T, H, O or U shaped cross section.

Preferably, each of the one or more than one articulated system of rods is coupled to the central shaft via at least one of the one or more than one common carrier. By means of the common carrier, forces acting on the articulated systems of rods are distributed and may be equalized. The articulated systems of rods may also be coupled to the central shaft without using common carriers.

Each of the one or more than one articulated system of rods comprises a first rod pivotally coupled to the central shaft and to the associated wall segment, and a second rod pivotally coupled to the central shaft and to the first rod, wherein at least one of the first rod and the second rod is slidably arranged on the central shaft. When one of the first rod and the second rod is slidably arranged on the central shaft, the other of the first rod and the second rod may be pivotally (i.e. not slidingly) arranged on the central shaft. Alternatively, each of the first rod and the second rod may be slidably arranged on the central shaft via an associated common carrier.

Further, the second rod may be pivotally coupled to the associated wall segment and the first rod or the second rod may be slidably arranged on the associated wall segment.

Preferably, the mechanical linkage comprises a plurality of articulated systems of rods arranged at an axial offset (i.e. at an offset in the axial direction in which the central shaft extends). This improves stability of the wall segments relative to the central shaft. Further, at least two of the plurality of articulated systems of rods may be oppositely arranged relative to each other in the axial direction. This arrangement further improves stability and rigidity of the mold to bear its own weight and that of the laminate thereon.

The dimension of the outer circumference of the mold may be continuously adjustable between a minimum dimension of the outer circumference and a maximum dimension of the outer circumference. This may be implemented by means of a continuously adjustable actuator.

According to a second aspect of the invention defined in claim <NUM>, the plurality of wall segments are configured to overlap along the outer circumference of the mold at least when the actuator is set to a minimum dimension of the outer circumference of the mold. Preferably, an overlap is maintained at a maximum dimension of the outer circumference of the mold.

The wall segments of the mold can be shaped as panels. This can facilitate overlap and/or contact between wall segments to prevent spaces between the wall segments, thus enabling an enclosed outer circumference. The wall segments, whether shaped as panels or not, can be bent along the outer circumference of the mold. Alternatively or additionally, the wall segments can be configured to contact neighboring wall segments when overlapping.

The mold may further comprise an object support configured to support a completed section of the tubular laminated object in alignment with the outer circumference of the mold defined by the plurality of wall segments. That is, the inner circumference of the completed section of the tubular laminated object is aligned with respect to the outer circumference of the mold by means of the object support. The completed section may be aligned in partial overlap with the outer circumference of the mold.

The object support may comprise a cap support configured to support a cap of the tubular laminated object. Preferably, the mold further comprises an extendable shaft configured to support the cap support and to extend in the axial direction. Preferably, the extendable shaft is arranged on or in the central shaft.

The axial direction may extend in an upright direction. Alternatively, the axial direction may extend in a horizontal direction. The mold may thus be configured for operation in an upright orientation or in a lying orientation. In latter case, the axial direction extends in the horizontal direction, or at least in a direction ± <NUM>° around the horizontal with respect to gravity.

The invention in a third aspect further provides a system as defined in claim <NUM> that is configured to produce tubular laminated objects, such as tanks and silos, wherein the system comprises a mold according to the first or second aspect of the invention and a cap mold configured to produce caps for tubular laminated objects, such as end caps for tanks and silos, on an outer surface of the cap mold, wherein a radial dimension of the outer surface of the cap mold is at least as large as a maximum radial dimension of the outer circumference of the mold.

Because of the relative radial dimensions of the mold and the cap mold, the cap mold is configured to produce laminated object caps that extend beyond any set dimension of the outer circumference of the mold to provide an overlap.

Preferably, the cap mold is conically shaped. The conical shape of the cap mold preferably comprises an inclination angle relative to the base plane of the cone in a range of <NUM>° - <NUM>°, more preferably <NUM>° - <NUM>° and most preferably of <NUM>°. These shapes and angles are preferred to provide strength to the cap produced using the cap mold without requiring excess laminate. A surprisingly advantageous balance is obtained between laminate thickness and strength in a cap of the shape, which is capable of carrying a tubular laminated object produced integrally with it.

Further, in a fourth aspect defined in claim <NUM>, the invention provides a method of producing tubular laminated objects, such as tanks and silos, with a mold according to the first or second aspect and/or a system according to the third aspect. The method comprises:.

The produced tubular laminated object thus has an inner circumference determined by the dimension of the outer circumference of the mold as set by (simultaneous) adjustment of the plurality of wall segments of the mold.

Preferably, at least one of the steps C and F is executed by an actuator of the mold. More preferably, each of the steps C and F are executed by the same actuator of the mold.

The method may further comprise a step B of arranging a cap at an axial end of the outer circumference of the mold and a step D of providing laminate onto the cap and overlapping with the outer circumference of the mold to produce the laminated tubular object with the cap integrated. Preferably, the method further comprises a step A of providing laminate onto an outer surface of a cap mold to produce the cap.

Alternatively or additionally, the method may further comprise a step G of shifting the produced tubular laminated object in the axial direction along the outer circumference, a step H of adjusting, preferably simultaneously adjusting, the position of each of the plurality of wall segments to hold the produced tubular laminated object in its shifted position and a step J of providing laminate onto the outer circumference of the mold to extend the produced tubular laminated object. The step H can be executed by an actuator of the mold, preferably the same actuator that is also used for the steps C and F.

Preferably, the step G comprises raising the mounted cap to a higher level and thereby raising the tubular laminated object produced integrally with the cap.

In the first aspect, the mold is improved with a particular adjustment mechanism.

This mold according to the first aspect can further comprise additional features described above in relation to the mold according to the invention.

With this mold according to the first aspect, it is further possible that the plurality of wall segments are at least one of: shaped as panels; and configured to overlap along the outer circumference of the mold at least when the actuator is set to a minimum dimension of the outer circumference of the mold. The plurality of wall segments can be configured to maintain overlap along the outer circumference of the mold when the actuator is set to a maximum dimension of the outer circumference of the mold.

In the second aspect, the mold enables overlap of wall segments. This mold is configured to produce tubular laminated objects, such as tanks and silos, on an outer circumference of the mold, wherein the mold comprises:.

wherein the plurality of wall segments are configured to overlap along the outer circumference of the mold at least when the actuator is set to a minimum dimension of the outer circumference of the mold. The wall segments may be shaped as panels.

Preferably, the plurality of wall segments is configured to maintain overlap along the outer circumference of the mold when the actuator is set to a maximum dimension of the outer circumference of the mold.

The mold according to this second aspect can further comprise additional features that are described above in relation to the mold of the first aspect as well as features defined in relation to the mold as disclosed herein. For example, the mold of the second aspect can be provided with an object support and/or an adjustment mechanism as described herein.

In a further aspect that is not independently claimed, the mold is configured to produce tubular laminated objects, such as tanks and silos, on an outer circumference of the mold, wherein the mold comprises:.

In this further aspect of the mold with the object support, the actuator is not essential nor does the adjustment need to occur simultaneously. This also applies to any mold as disclosed herein which comprises an object support.

Preferably, the object support comprises a cap support configured to support the cap of the tubular laminated object. Further, this mold can further comprise an extendable shaft configured to support the object support and to extend in the axial direction. More preferably, the extendable shaft supports the cap support comprised by the object support. The extendable shaft can be arranged on or in the central shaft.

The mold according to the further aspect can also comprise features of the mold of the first aspect and/or the second aspect. For example, the mold can comprise an object support in addition to panel-shaped wall segments or adjustable connectors of any form herein disclosed. Finally, the cap support can be provided separately from the object support.

Aspects of the disclosure are further explained using the appended figures, in which:.

<FIG> show different views of a first embodiment of a mold <NUM> according to the invention, which also comprises various preferred yet optional features. The mold <NUM> is configured to produce tubular laminated objects <NUM> on an outer circumference of the mold <NUM>. The produced tubular laminated objects <NUM> may serve as (segments of) tanks and silos and may be open at both ends or comprise a cap <NUM> at one or at both of its ends.

The mold <NUM> comprises a central shaft <NUM> extending in an axial direction <NUM>. A plurality of wall segments <NUM> extends in the axial direction <NUM>, surrounds the central shaft <NUM> and defines the outer circumference of the mold <NUM>. The tubular laminated object <NUM> is to be produced on the outer circumference, thus on the plurality of wall segments <NUM>. In practice, an intermediate layer such a plastic film may be disposed on the outer circumference of the mold before laminating the tubular laminated object <NUM> onto the plurality of wall segments <NUM>. As shown in <FIG>, the wall segments <NUM> can be shaped as panels, thus forming wall panels <NUM>. The wall segments or panels <NUM> can be configured to mutually define a continuous outer circumference of the mold <NUM>. In addition or alternatively, the wall segments <NUM> can be bent along the outer circumference of the mold and/or configured to contact neighboring wall segments <NUM>. For example, the wall segments or panel <NUM> can include a bend or kink line extending in the axial direction <NUM> along the wall segment or panel <NUM> to provide at least two planar sections in the at least partly planar surface of the wall segment or panel <NUM>. This facilitates setting of the dimension of the outer circumference of the mold <NUM> and any overlapping of wall segments <NUM>, which can involve contact between neighboring wall segments or panels <NUM>. A wall panel <NUM>, optionally having said bend or kink line, is preferred for simplicity of manufacturing over a fully curved or rotatable wall segment <NUM>, though these are also possible.

Further, the mold <NUM> comprises an actuator <NUM> configured to set a dimension of the outer circumference of the mold <NUM> by simultaneously adjusting a radial distance of each of the plurality of wall segments <NUM> relative to the central shaft <NUM>.

In the first embodiment, the central shaft <NUM> includes an optional spacer frame <NUM> configured to enlarge a radial dimension of the central shaft <NUM>. The spacer frame <NUM> enables a radial offset in the dimension of the outer circumference and presents an enlarged perimeter for mounting the wall segments <NUM>, thereby providing a strong and stiff construction of the mold <NUM> even at large dimensions of the outer circumference, for example diameters over <NUM>.

The mold <NUM> according to the illustrated first embodiment further comprises a plurality of adjustable connectors <NUM> each arranged between an associated wall segment <NUM> of the plurality of wall segments <NUM> and the central shaft <NUM> and configured to adjust the radial distance of the associated wall segment <NUM> relative to the central shaft <NUM> in response to actuation by the actuator <NUM>. That is, each adjustable connector <NUM> is associated with a wall segment <NUM>. As illustrated, each adjustable connector <NUM> is configured to maintain the associated wall segment <NUM> substantially parallel to the axial direction <NUM>. Thereby, the outer circumference of the mold <NUM> and thus the tubular laminated object <NUM> produced with it, comprises a substantially constant cross section along the axial direction <NUM>. Alternatively, angled configurations are possible to provide a frustoconical shape in the outer circumference of the mold <NUM>.

As illustrated in <FIG>, each adjustable connector <NUM> comprises two mechanical linkages <NUM>. The mechanical linkages <NUM> of each adjustable connector <NUM> are arranged in a radial plane between the central shaft <NUM> and the associated wall segment <NUM>. The mechanical linkages <NUM> may thus be considered planar.

Further, two common carriers <NUM> are connected to the mechanical linkages <NUM> of the plurality of adjustable connectors <NUM>. Here, the actuator <NUM> is configured to adjust a position of the common carriers <NUM> to thereby simultaneously actuate the mechanical linkages <NUM> and set the dimension of the outer circumference of the mold <NUM>. In particular, the position of the common carriers <NUM> is adjustable in the axial direction <NUM> and each mechanical linkage <NUM> is configured to convert adjustment of the position of the common carriers <NUM> into adjustment of the radial distance of the associated wall segment <NUM> relative to the central shaft <NUM>. As illustrated, it is preferred that the common carriers <NUM> surround the central shaft <NUM> and are movable along the central shaft <NUM>.

The working of this mechanism is particularly clear from <FIG>. When the actuator <NUM>, here illustrated as a plurality of hydraulic cylinders, acts on the common carriers <NUM>, it adjusts their position along the axial direction <NUM>. The common carriers <NUM> here slide along guiding beams which present a support surface <NUM> to the common carriers <NUM>. In turn, the mechanical linkages <NUM> coupled to the common carriers <NUM> follow this movement along the axial direction <NUM> and by their construction convert this axial movement in a radial adjustment of the position of the wall segment <NUM> coupled to the mechanical linkages <NUM>. Various implementations of the mechanical linkages <NUM> are explained in relation to <FIG>.

It is preferred that the dimension of the outer circumference of the mold <NUM> is continuously adjustable between a minimum dimension of the outer circumference and a maximum dimension of the outer circumference. Alternatively or additionally, the plurality of wall segments <NUM> are configured to overlap along the outer circumference of the mold at least when the actuator <NUM> is set to a minimum dimension of the outer circumference of the mold <NUM>. In <FIG>, the mold <NUM> is shown at the maximum dimension of the outer circumference, which is here obtained by extending the plurality of hydraulic cylinders which from the actuator <NUM> to their maximum length and thereby pushing the common carriers <NUM> to a maximum outward position along the axial direction <NUM> which in turn act on the plurality of mechanical linkages <NUM> that carry the plurality of wall segments <NUM> to a maximum radial distance from the central shaft <NUM>.

It is preferred that the mold <NUM> further comprises an object support <NUM> configured to support a completed section <NUM> of the tubular laminated object <NUM> in alignment with the outer circumference of the mold <NUM> defined by the plurality of wall segments <NUM>. This arrangement makes it possible to laminate an extension section <NUM> of the tubular laminated object <NUM> on the outer circumference of the mold <NUM> when the completed section <NUM> of the tubular laminated object <NUM> is in a shifted position along the axial direction <NUM>, thus freeing at least part of the outer circumference of the mold <NUM> and making it available for further applying laminate thereon.

The object support <NUM> may be implemented in various ways. As illustrated for the first embodiment, the object support <NUM> comprises a cap support <NUM> configured to support a cap <NUM> of the tubular laminated object <NUM>. The mold <NUM> of this embodiment further comprises an optional extendable shaft <NUM> configured to support the cap support <NUM> and to extend in the axial direction <NUM>. The extendable shaft <NUM> is preferably arranged on or in the central shaft <NUM>. In the illustrated first embodiment, a heavy-duty hydraulic cylinder may be arranged in the central shaft <NUM> to provide a lifting force for adjusting a position of the extendable shaft <NUM> along the axial direction <NUM>. Preferably, the same actuator <NUM> is used to actuate the extendable shaft <NUM> and the plurality of wall segments <NUM>. For example, when using hydraulic cylinders, the actuator <NUM> may comprise a common source of adjustable hydraulic pressure.

The object support <NUM> of the first embodiment may be seen as an internal object support arranged within the outer circumference of the mold <NUM>. Alternatively or additionally, the object support <NUM> may comprise an external support configured to support the completed section <NUM> of tubular laminated object <NUM> from outside the outer circumference of the mold <NUM>. Whether internal or external, the object support <NUM> preferably carries the weight of the completed section <NUM> of the tubular laminated object <NUM> and may be placed on a production floor or be suspended from a crane. When the object support <NUM> is not arranged on the mold <NUM>, it preferably comprises rollers over which the completed section <NUM> may roll when the mold <NUM> is rotated. The object support <NUM> may be configured to prevent sagging of the completed section <NUM> or bending of the completed section <NUM> relative to the extension section <NUM>. Further, it may reduce torsion between the completed section <NUM> and the extension section <NUM> of the tubular laminated object <NUM> when providing laminate onto the outer circumference of the mold <NUM> during rotation of the mold <NUM>.

The first embodiment of the mold <NUM> may advantageously be employed with the axial direction <NUM> extending in an upright direction. That is, the mold lof <FIG> may stand on a production floor with the central shaft <NUM> upright.

<FIG> shows a second embodiment of the mold <NUM>. This second embodiment shares many features with the first embodiment shown in <FIG>. Repeating descriptions of corresponding features is omitted here for conciseness.

To better illustrate the second embodiment, only one wall segment <NUM> is illustrated in <FIG>. The wall segment <NUM> is coupled to the central shaft <NUM> via an adjustable connector <NUM>. In contrast to the first embodiment, the central shaft <NUM> does not comprise a spacer frame <NUM> here, allowing smaller dimensions of the outer circumference of the mold <NUM> in this case. The adjustable connector <NUM> here comprises four of mechanical linkages <NUM>, each arranged between the wall segment <NUM> and the central shaft <NUM>. Each mechanical linkage <NUM> is coupled to a common carrier <NUM>. However, any number of mechanical linkages <NUM> and / or common carriers <NUM> can be employed.

The common carriers <NUM> here comprise rollers <NUM> which are supported by a support surface <NUM> of the central shaft <NUM>. In this embodiment, the actuator <NUM> is configured to adjust a position of the common carriers <NUM> along the central shaft <NUM> in the axial direction <NUM>. For example, the actuator <NUM> may comprise one or more hydraulic cylinders configured to act on the common carriers <NUM>.

The axial direction <NUM> here extends in a horizontal direction. The central shaft <NUM> is supported by a base <NUM> configured to suspend the mold <NUM>. The second embodiment of the mold <NUM> is particularly suitable for use in a lying orientation with the axial direction horizontal, while the first embodiment of the mold <NUM> is particularly suitable for a standing orientation with the axial direction upright. In a standing mold, larger dimensions of the outer circumference can be obtained compared to a horizontal mold because of an improved transfer of gravitational forces in standing molds. However, lying molds provide improved access to the outer circumference of the mold <NUM> allowing faster production.

The mold <NUM> of <FIG> further comprises an object support <NUM> which is arranged at an end of the outer circumference of the mold <NUM>. The object support <NUM> is configured to support a completed section <NUM> of the tubular laminated object <NUM> in alignment with the outer circumference of the mold <NUM> defined by the plurality of wall segments <NUM>, understood to be part of the mold <NUM> according to the second embodiment, though not illustrated. The object support <NUM> is implemented here with four radial object supports <NUM> which are radially adjustable. When a completed section <NUM> of the tubular laminated object <NUM> is shifted along the outer circumference of the mold <NUM> in the axial direction <NUM>, it may be held in that position by the plurality of wall segments <NUM> (at least the ends thereof) and by the radial object supports <NUM>. The wall segments <NUM> and the radial object supports <NUM> may be set to the same dimension of the outer circumference to achieve this, when the tubular laminated object <NUM> is cylindrical. Torsion is then reduced between the completed section <NUM> and the extension section <NUM> which is then produced by providing laminate onto the outer circumference of the mold <NUM>, generally while rotating the mold <NUM> or at least its outer circumference.

Though <FIG> and <FIG> show the actuator <NUM> embodied as a plurality of hydraulic cylinders, a plurality of screw spindles can also be employed. Further, it is conceivable that the actuator <NUM> is formed by a single hydraulic cylinder or screw spindle, or a combination thereof.

Though the first and second embodiments of the mold <NUM> are described separately, features of these two embodiments may be combined. For example, the base <NUM> and / or radial object supports <NUM> of <FIG> may be employed with the mold <NUM> of <FIG> while the cap support <NUM> and / or extendable shaft <NUM> of <FIG> may be implemented with the mold <NUM> of <FIG>.

<FIG> show variants of a mechanical linkage <NUM> which may be employed in any of the embodiments of the mold <NUM> according to the invention. In particular, the adjustable connector <NUM> may comprise one or more of the illustrated mechanical linkages <NUM>.

The mechanical linkage <NUM> may comprises one or more than one articulated system of rods <NUM> configured to couple the associated wall segment <NUM> to the central shaft <NUM>. For example, each mechanical linkage <NUM> comprises at least one articulated system of rods <NUM> having an inner end coupled to the central shaft <NUM> and an outer end coupled to the respective one of the plurality of wall segments <NUM> that is coupled to the mechanical linkage <NUM>. Preferably, each of the one or more than one articulated system of rods <NUM> is coupled to the central shaft <NUM> via at least one of the one or more than one common carrier <NUM>.

In the illustrated variants, the articulated system of rods <NUM> comprises a first rod <NUM> pivotally coupled to the central shaft <NUM> and to the associated wall segment <NUM> and a second rod <NUM> pivotally coupled to the central shaft <NUM> and to the first rod <NUM>. At least one of the first rod <NUM> and the second rod <NUM> is/are slidably arranged on the central shaft <NUM>.

In <FIG>, the articulated system of rods <NUM> presents lambda-shaped configuration when viewing the articulated system of rods <NUM> sideways (i.e. along an axis perpendicular to a radial plane between the central shaft <NUM> and the wall segment <NUM>), while in <FIG> it presents an X-shaped configuration and in <FIG> it presents a V-shaped configuration. These configurations may be summarized in other words: the first rod <NUM> is coupled to the central shaft <NUM> at its radially inner end and to the wall segment <NUM> at is radially outer end, while the second rod <NUM> is coupled to the central shaft <NUM> at its radially inner end and at to the first rod <NUM> at a distance from the inner end of the first rod that is coupled to the central shaft.

Because the first rod <NUM> and a second rod <NUM> are pivotally coupled towards the central shaft <NUM> at a mutual distance adjustable by the actuator <NUM>, each of the illustrated articulated systems of rods <NUM> provide a simple yet effective construction. They provide leverage to action of the actuator <NUM> acting in the axial direction to adjust a radial position of the wall segment <NUM>. Further, a stabile construction is provided which allows a continuously adjustable range of outer circumference accessible by the mold <NUM>. Further, this range is enlarged compared to that of conventional molds.

As shown in <FIG>, each of the first rod <NUM> and the second rod <NUM> may be slidably arranged on the central shaft <NUM> via an associated common carrier <NUM>. When both the first rod <NUM> and the second rod <NUM> are each coupled to a respective common carrier <NUM> (that is, two different common carriers <NUM> from among a plurality of common carriers <NUM>), the actuator <NUM> may be fixed with respect to the axial direction <NUM> and configured to adjust a separation between the common carriers <NUM> of the first rod <NUM> and second rod <NUM>.

As shown in <FIG>, the second rod <NUM> may be pivotally coupled to the associated wall segment <NUM>. Further, the first rod <NUM> or the second rod <NUM> may be slidably arranged on the associated wall segment <NUM>, for example via a slider <NUM> as illustrated in <FIG>.

The mechanical linkage <NUM> may comprise a plurality of articulated systems of rods <NUM> arranged at an axial offset. In other words, each mechanical linkage <NUM> may comprise at least two similar or different articulated systems of rods <NUM> which are mutually spaced apart in the axial direction <NUM>. Consequently, each of the plurality of wall segments <NUM> is connected to the central shaft <NUM> via at least two articulated systems of rods <NUM>. When spacing apart the plurality of articulated systems of rods <NUM> in the axial direction <NUM>, the mold <NUM> can better accommodate movement of common carriers <NUM> associated with the plurality of articulated systems of rods <NUM>. Examples of such arrangements are given in <FIG>.

When the mechanical linkage <NUM> comprises a plurality of articulated systems of rods <NUM> arranged at an axial offset, multiple common carriers <NUM> may be employed, each coupled to at least one of the plurality of articulated systems of rods <NUM> of the mechanical linkage <NUM>. These common carriers <NUM> may be mutually connected by connection beams <NUM> in order to fix their mutual spacing in the axial direction <NUM> in order to stabilize positioning of the articulated systems of rods <NUM> coupled to these common carriers <NUM>. This stabilizes the radial position of the plurality of wall segments <NUM> held by the mechanical linkages <NUM>, thus more accurately setting the outer circumference of the mold <NUM>. For example, as illustrated in <FIG>, the two common carriers <NUM> nearest the object support <NUM> are coupled via connection beams <NUM>. When these two common carriers <NUM> are moved along the axial direction <NUM> towards the object support <NUM>, each mechanical linkage <NUM> increases the radial distance between the wall segment <NUM> and the central shaft <NUM> (and vice versa). The remaining two common carriers <NUM> in <FIG> work similarly, though in the opposite direction. The connection beams <NUM> thus stabilize the mutual positioning of the common carriers <NUM>.

At least two of the plurality of articulated systems of rods <NUM> may be oppositely arranged relative to each other in the axial direction <NUM>. The at least two of the plurality of articulated systems of rods <NUM> may thus define a mirrored pair or articulated systems of rods <NUM>, that is one of the articulated system of rods <NUM> of the pair is reversed with respect to the other of the pair.

<FIG> shows a preferred embodiment of a cap mold <NUM> for a system according to the invention. The system is configured to produce tubular laminated objects <NUM>, such as tanks and silos, which may advantageously comprise a cap <NUM> at one or both ends. The system comprises a mold <NUM> according to the invention and a cap mold <NUM>. The cap mold <NUM> is configured to produce caps <NUM> for tubular laminated objects <NUM>, such as end caps for tanks and silos, on an outer surface of the cap mold <NUM>. A radial dimension of the outer surface of the cap mold <NUM> is at least as large as a maximum radial dimension of the outer circumference of the mold <NUM>.

In the illustrated embodiment, the cap mold <NUM> is conically shaped. It is preferred that an inclination angle α relative to the base plane of the cone is in a range of <NUM>° - <NUM>°, more preferably <NUM>° - <NUM>° and most preferably of <NUM>°. The fixed inclination angle, rather than conventional dome-shapes for end caps, allows use of a single cap mold <NUM> in combination with a single mold <NUM> to produce tubular laminated products <NUM> of various dimensions in a time and resource efficient way.

It is noted that these inclination angles α correspond aperture angles θ of the conical shape in a range of <NUM>° - <NUM>°, <NUM>° - <NUM>° and <NUM>°, respectively. A right circular cone shape is preferred to match with circular tubular laminated objects <NUM>. However, oval, egg-shaped or polygonal shapes are also possible for the cap mold <NUM> as well as for the mold <NUM>.

Further, the conical shape of the cap mold <NUM>, especially at the mentioned angles, allows compliant overlap between a laminated object cap <NUM> and the outer circumference of the mold <NUM> so that the tubular laminated object <NUM> may be laminated in overlap with the laminated object cap <NUM>.

When the system comprises a mold <NUM> with a cap support <NUM>, the cap support <NUM> is preferably configured to match a shape of the cap <NUM> obtained with the cap mold <NUM>.

<FIG> and <FIG> illustrate advantageous first and second embodiments of a method of producing tubular laminated objects, such as tanks and silos, with a mold <NUM> comprising a plurality of wall segments <NUM> defining an outer circumference of the mold <NUM>. The method according to the invention is advantageously implemented by the mold <NUM> according to the first and/or second aspects of the invention. In particular, the mold <NUM> illustrated in <FIG>, preferably in combination with the cap mold <NUM> illustrated in <FIG>, may be employed advantageously to implement the method of <FIG> while the mold <NUM> illustrated in <FIG> may be employed advantageously to implement the method of <FIG>.

In both illustrated embodiments of the method, it comprises a step C of simultaneously adjusting a position of each of the plurality of wall segments <NUM> to set a dimension of the outer circumference of the mold <NUM>, a step E of providing laminate onto the outer circumference of the mold <NUM> to produce a tubular laminated object <NUM>, and a step F of simultaneously adjusting the position of each of the plurality of wall segments <NUM> to decrease the dimension of the outer circumference of the mold <NUM> and thereby release the produced tubular laminated object <NUM> from the mold <NUM>. A tubular laminated object <NUM> is thus produced.

Step E is generally performed while rotating the mold <NUM> around the axial direction <NUM> while a source of laminate is moved along the outer circumference of the mold <NUM> in the axial direction <NUM>.

At least one of step C and step F may be executed by an actuator <NUM> of the mold <NUM>. Preferably, both step C as well as step F are performed with the same actuator <NUM> of the mold <NUM>. That is, both the setting as well as the decreasing of the dimension of the outer circumference of the mold <NUM> may be performed by means of the actuator <NUM>.

In <FIG>, further optional steps are illustrated. In a step B, a cap <NUM> is arranged at an axial end of the outer circumference of the mold <NUM>. In a step D, laminate is provided onto the cap <NUM> and overlapping with the outer circumference of the mold <NUM> to produce the laminated tubular object <NUM> with the cap <NUM> integrated. This may result in overlap section <NUM>. In an optional preceding step A, laminate is provided onto an outer surface of a cap mold <NUM> to produce the cap <NUM>.

Though it is preferred that the cap <NUM> is a laminated object, it may be produced otherwise and / or from different materials, e.g. injection molding plastic or die casting metal. Thus, the step A is optional and need not be performed even when step B is performed in the method.

In step B, the cap <NUM> may be mounted at or partially overlapping with an end of the plurality of wall segments <NUM> in the axial direction <NUM>. The cap <NUM> can be mounted on the mold <NUM> in partial overlap by having a radial dimension that exceeds the radial dimension obtained in the step C of setting the dimension of the outer circumference of the mold <NUM>. The cap <NUM>, in particular when it is produced in the step A as a laminated object cap <NUM>, is thus dimensioned for the set outer circumference of the mold <NUM>, wherein the laminated object cap <NUM> provides an overlap so that in step D laminate can be provided onto the cap <NUM> in overlap with the outer circumference of the mold <NUM>.

The order of steps B and C can be changed, i.e. the setting of the dimension of the outer circumference of the mold <NUM> may precede or follow the step of arranging the cap <NUM> on the mold <NUM>. The step D can be integral to the step E but may also be performed separately.

The methods of <FIG> and <FIG> further comprise three optional steps: a step G of shifting the produced tubular laminated object <NUM> in the axial direction <NUM> along the outer circumference of the mold <NUM>, a step H of simultaneously adjusting the position of each of the plurality of wall segments <NUM> to hold the produced tubular laminated object <NUM> in its shifted position, and a step J of providing laminate onto the outer circumference of the mold <NUM> to extend the produced tubular laminated object <NUM>.

In step G, a completed section <NUM> of the tubular laminated object <NUM> may be shifted along the outer circumference of the mold <NUM> to make space for laminating an extension section <NUM> of the tubular laminated object <NUM> onto the same outer circumference of the mold <NUM> in step J. The extension section <NUM> may be laminated integrally with the completed section <NUM>, for example by providing laminate in overlap onto the produced tubular laminated object to obtain an overlap section <NUM>. The overlap section <NUM> may form a sleeve joint.

In step H, the simultaneously adjusting of the position of each of the plurality of wall segments <NUM> may result in their return to the previously set dimension of the outer circumference (step C). The step H is preferably executed by the actuator <NUM> of the mold <NUM>. An object support <NUM>, such as a cap support <NUM> and / or radial object supports <NUM>, may also aid in holding the tubular laminated objected <NUM> in its shifted position.

After completion of step J, step F may again be performed to release the tubular laminated product <NUM> from the mold <NUM>.

In <FIG>, the step G comprises raising the mounted cap <NUM> to a higher level and thereby raising the tubular laminated object <NUM> produced integrally with the cap <NUM>. This shows an advantageous use of the cap <NUM> during production of the tubular laminated object <NUM>. The shifting of the produced tubular laminated object <NUM> along the mold <NUM> in step G may comprise extending an extendable shaft <NUM> of the mold <NUM>, for example in a vertically arranged mold <NUM> illustrated in <FIG>. The extendable shaft <NUM> may also contribute to the holding the produced tubular laminated object <NUM> in its shifted position. Alternatively or additionally, the produced tubular laminated object <NUM> may be shifted and by means of a crane and held by internal and / or external object supports.

By using the cap <NUM> in the way illustrated in step G of <FIG>, the method enables production of relatively large diameters compared to a horizontal production method such as the embodiment illustrated in <FIG>. In a horizontal configuration of the mold <NUM>, larger diameters would become too heavy, whereas upright configurations can better carry the combined laminated mass, in particular by means of the cap <NUM>, which ensures an advantageous distribution of mass. Sufficient length of the tubular laminated object <NUM>, e.g. extending beyond a dimension of the mold <NUM> in the axial direction <NUM>, can be achieved by joining the sections <NUM>, <NUM> together as illustrated in <FIG> or <FIG>, or in conventional ways after removing sections from the mold <NUM>. A horizontal configuration may be preferred for production speed while an upright configuration may be preferred for large product diameters.

Claim 1:
Mold (<NUM>) configured to produce tubular laminated objects (<NUM>), such as tanks and silos, on an outer circumference of the mold (<NUM>), wherein the mold (<NUM>) comprises:
- a central shaft (<NUM>) extending in an axial direction (<NUM>);
- a plurality of wall segments (<NUM>) extending in the axial direction (<NUM>), surrounding the central shaft (<NUM>) and defining the outer circumference of the mold (<NUM>);
- an actuator (<NUM>) configured to set a dimension of the outer circumference of the mold (<NUM>) by simultaneously adjusting a radial distance of each of the plurality of wall segments (<NUM>) relative to the central shaft (<NUM>); and
- a plurality of adjustable connectors (<NUM>) each arranged between an associated wall segment (<NUM>) of the plurality of wall segments (<NUM>) and the central shaft (<NUM>) and configured to adjust the radial distance of the associated wall segment (<NUM>) relative to the central shaft (<NUM>) in response to actuation by the actuator (<NUM>), wherein each adjustable connector (<NUM>) comprises a mechanical linkage (<NUM>) comprising one or more than one articulated system of rods (<NUM>) configured to couple the associated wall segment (<NUM>) to the central shaft (<NUM>), wherein each of the one or more than one articulated system of rods (<NUM>) comprises:
- a first rod (<NUM>) pivotally coupled to the central shaft (<NUM>) at its radially inner end and to the associated wall segment (<NUM>) at its radially outer end;
- a second rod (<NUM>) pivotally coupled to the central shaft (<NUM>) and to the first rod (<NUM>); and
- wherein at least one of the first rod (<NUM>) and the second rod (<NUM>) is slidably arranged on the central shaft (<NUM>).