EP3066042A1

EP3066042A1 - Compactable tube

Info

Publication number: EP3066042A1
Application number: EP14795624.7A
Authority: EP
Inventors: Santos HERNÁNDEZ MUÑOZ
Original assignee: Individual
Current assignee: Individual
Priority date: 2013-11-07
Filing date: 2014-11-06
Publication date: 2016-09-14
Anticipated expiration: 2034-11-06
Also published as: WO2015067699A1; ES1096630U; ES1096630Y; EP3066042B1

Abstract

A compactable tube comprising a band (40) that can be wound into a helix form (44) or cylindrical tube, having on the longitudinal edges thereof and in the direction parallel to the plane of the band (40) zipper teeth (42) for fixing one edge with the opposite edge. The band (40) that is not wound is maintained in a spiral (45) or reel, perpendicular or oblique to the helix, from which there is provided a slider (48) for assembling or disassembling it. The compactable tube can comprise a rotary bending nut (46) where the band (40) is inserted and which, in the rotation thereof, assembles the edge of the band (40) on the corresponding edge of the helix (44), or disassembles it therefrom, by means of the slider (48) and guide screws (49', 49).

Description

COMPACTABLE TUBE

TECHNICAL FIELD The present invention relates to a compactable tube, mainly for use in the technical sector of linear actuators and telescopic supports.

PRIOR ART Tubes (appendices, linear actuators, supports, props, struts, legs, telescopic lighting, etc.) that are compactable, retractile, packable, detachable, retractable, etc., typical for supporting a mechanical load, are primarily based on concentric telescopic cylinders, conserving a minimum length that is significant with respect to the total length once retracted or compacted, attempting to minimize the number of concentric segments to improve stability, rigidity, stiffness and robustness of the support, which goes against the degree of compaction. In other words, rigidity and compaction in these telescopic devices are inversely proportional. Furthermore, concentric cylinders lose in diameter as they are being inserted into the upper tube, also imposing physical limitations to the robustness of the support. There is currently a US patent, US 4875660 A (Pierre Gagnon, Pierre Laforest), marketed as a "spiralift", which protects the invention of a lifting device assembling a cylindrical metal tube from two spiral bands that extend into a helix form, in a mechanical and motorized manner for raising platforms linearly. This device is compact, stable, has a low cost, requires little maintenance, has a high capacity, is versatile and flexible (it can be installed on an existing floor without a pit), easy-to-install (it is installed within a short time), not affected by temperature changes (such as hydraulic actuators), needs very little wiring, allows several actuators to be coordinated and synchronized to achieve versatile solutions, operates quietly, does not need a room with hydraulic pumps, has operative and supported solutions and is approved worldwide. Another related patent is US 2173685 A (Erich Grassmann) protecting the invention of a lifting device assembling a cylindrical metal tube from a band which extends following the path of a helix, in a mechanical and motorized manner.

The difference between the invention proposed in this document and document US 2173685 A consists of the fact that the system for linking the band proposed in this document is a system consisting of profiles, notched, toothed profiles optionally in the form of a zipper, on the opposite edges of a single band, whereas in document US 2173685 A the linking takes place by means of successive overlapping male-female attachments, between projections and complementary holes existing on the surface of the band (not on the edge). Therefore, the faces of the resulting cylinder are not smooth, the bands are superimposed on the surface of the tube (there being no front assembly on the vertical edges but rather lateral assembly) and finally, the radius of the cylinder is not constant. Another patent related to the technical sector is FR2826422 A1 (Bourc His Joel). This invention also generates a compactable tube but its features are different from those of the solution proposed in this document.

DISCLOSURE OF THE INVENTION

The technical effect resulting from differences of the invention in its different embodiments with the state of the art involve is to provide an alternative attachment between the edges of the band for assembling the cylinder, having good mechanical strength characteristics, a smooth tube surface, a constant cylinder radius and leak-tightness.

The invention object of this description consists of a hollow helical cylindrical tube which can be compacted in a circular spiral form. In other words, it can be assembled and disassembled in a reversible manner to free up space and to reduce its size to facilitate handling and transport. When extended, the appendix adopts the form of a hollow helical cylindrical tube and when retracted, it adopts the form of a circular spiral. The tube is assembled from a single band, initially in a spiral form, by means of a mechanism, by way of a zipper on its two profiled edges, to generate a helical cylindrical appendix, when fastening the opposite edges of the band.

For assembling the band, a slider which brings together the edges in the suitable path for fastening is used. The slider is inserted in a rotary bending nut producing the helical paths necessary for the slider to fasten the band by means of two screws, one inner screw and another outer screw.

The slider will generally be of the type referred to hereinafter as non-coplanar because it brings together the edges of the band in different planes for fastening.

The appendix thus formed, although depending on the material used for the band and the structure of the edges, is smooth, stable, rigid and robust due to the strength of the helical cylindrical structure, taking advantage of the reinforcement of winding up the band to support longitudinal compression and tensile stresses and lateral stresses due to the strength of the engaging of the zipper or joint, joining the edges of the band. The band itself does not have this strength until it adopts the helical cylindrical form, conferring it the structural advantages of a tube when it has to support weight, under compression or under traction. In this device, the degree of compaction is independent from the rigidity, both being very high. Additionally, the diameter of the support, thus assembled, can be kept perfectly constant for the entire length thereof. Leak- tightness of the tube can also be achieved by means of the appropriate design and use of suitable materials. This appendix or helix can be used in linear actuators, telescopes, periscopes, tripods, toys, tools, drill columns, walking sticks, masts, retractile lighting elements, etc., whereas the independent tube can be used as a document cover, for example, and the non-coplanar slider can be used for plate or sheet closures, for example. Particularly, the compactable tube of the invention comprises a band that can be wound into a helix form or cylindrical tube, having on the longitudinal edges thereof and in the direction parallel to the plane of the band zipper teeth for fixing one edge with the opposite edge, and having a slider for assembling or disassembling the zipper. The teeth can be part of complementary edges and be arranged inside an upper L-shaped rib having a width less than the width of the band.

The band can further comprise a longitudinal neck, with or without notching, close to the teeth. The band is preferably arranged in a spiral, spool or reel before being placed in the helix, this spiral being able to be oblique to the helix, with the angle of development a of the helix, such that it is not bent when placed in the assembled or disassembled position.

The slider can comprise cogwheels for driving and linking the band by its teeth.

A preferred embodiment comprises a rotary bending nut, where the band is inserted and which, when it rotates, assembles the edge of the band on the corresponding edge of the helix, or disassembles it therefrom, by means of the slider, also being able to comprise a screw for guiding the band. In one embodiment, a blocking brake pressing the band against the screw, preventing the advancement thereof, would be arranged on this screw.

If desired, two or more intercalated bands can be arranged to form the helix, such that each band joins with the adjacent band and not itself. To control the rigidity, stiffness, of the tube, electroactive tape having variable rigidity, stiffness, in the band can be included, or a tension cable can be included between the ends of the helix.

The tube can comprise levels in the platform operating the helix to facilitate orienting same with respect to the direction of the force of gravity. Instead of teeth, or in addition to them, an alternative to the zipper consists of arranging complementary profiles, a first U-shaped profile with a curved central hole and a pivot and a second profile with a rod, such that the support and rotation of the second profile on the first profile, supported in the pivot, introduces the rod into the central hole.

For some uses, the present invention preferably has a cover in at least one end of the helix (or the two opposite sides, if it is a document cover, for example). DESCRIPTION OF THE DRAWINGS

The following drawings are included to better understand the invention:

Figure 1 shows a schematic view of the extended band which will form the tube.

Figure 2 shows a view of the band as a helix.

Figure 3 shows a schematic view of the band according to an embodiment but now having teeth on its two edges.

Figure 4 shows a view of the helix assembled from the band of Figure 3.

Figure 5 shows a view of the helix with non-coplanar fastening/unfastening. Figure 6 shows rear and front views of a schematic example of a non-coplanar sliding slider.

Figure 7 shows several views of the semi-rigid band with the protected zipper according to an embodiment: Figure 7A shows a perspective view of the band; Figure 7B shows a detail of the complementary edges; Figure 7C shows a view of the bands attached to another; Figure 7D shows a view of the edges at the height of the teeth when the slider passes over them.

Figure 8 shows a section plan view of a rotary bending nut with a non-coplanar sliding slider.

Figure 9 shows a section plan view of a rotary bending nut with non-coplanar bearing slider.

Figure 10 shows a perspective view of a cylindrical compactable tube with a rotary bending nut and a non-coplanar sliding slider.

Figure 1 1 shows section views of the profile for a semi-rigid band with a joint complementary by rotation and twisting: Figure 1 1 A shows the section of the band of the complementary profiles in detail; Figure 1 1 B shows the fixing/rotating steps.

Figure 12 shows a profile section view for a semi-rigid band with a joint, complementary without twisting, in detail.

Figure 13 shows a front view, side view and perspective view of the path of the semi-rigid profiled band with a joint complementary without twisting from the spiral position to the helical position. Figure 14 shows a perspective view of the channeled bearing rotary bending nut according to Figure 13, for the profile according to Figure 12, with the path for assembling the semi-rigid band with a joint complementary without twisting and containing the bearing slider and the outer and inner screws. Figure 15 shows a section view and plan view of the rotary bending nut of Figure 14 with the channels of the inner path and the cylindrical bearings arranged for guiding the band in the path of the conical helix required for assembling the profile of Figure 12.

Figure 16 shows views of a configuration with a spool/coil of band oblique to the tube.

Figure 17 shows views of a configuration with a spool/coil of band perpendicular to the tube.

DETAILED DISCLOSURE OF THE INVENTION The description of the invention can be provided in a constructive and sequential manner from the description of the relation between the length of the band (40) and the height of the helix to the possible optional mechanization of the tube assembly. The steps in which the description will be organized are the following: 1 . Relation between the length of the band (40) and the height of the helix

2. Characteristics of the edges of the band (40)

3. Helical assembly topology for assembling a cylinder (optional)

4. Mechanism for assembling the cylindrical tube (optional)

5. Mechanization/motorization of the mechanism for automatic assembly (optional)

Relation between the length of the band (40) and the height of the helix

The band (40) is a rectangular parallelepiped, the length of which will be referred to as "L", the height or width as "A", and the thickness as "g" (Figure 1 ). The height of the helix (44) or appendix "H", in a cylindrical helix form (44) or hollow tube, will in turn be the pitch of the helix (44) or turn "P", multiplied by the number of turns giving rise to the length "L" of the band (40) with a radius "R" of a specific cylinder.

The angle of development of the helix (44) is "a", the opposite cathethus is "P" and the contiguous cathethus "c", is 2-TT- R, therefore the hypotenuse "h" is JP² + (2nR)².

The tg a = P/(2-TT- R). In other words, "a" and "R" are related and are inversely proportional (whereas "P" increases with "a"), therefore each turn with an angle "a" takes up^'JP² + (2nR)² of the total length of the band (40), and as a result, for a given band (40), the greater the inclination (greater "a") of the development on the cylinder, the smaller the radius "R" and the greater the height "H" reached by the helix (44) with the same length "L".

With a minimum angle "a", the entire length of the band (40) would be taken up in a single turn (of maximum radius "R", with a value of the length of the diagonal of the band (40) is the

length of the circumference of the cylinder) and the height of the cylinder "H" would be minimal.

At the other end, with a maximum angle "a" (90°) the height of the tube "H" would be the length of the band (40) "L" (with minimum "R" having a value of ^), and the length of the circumference of the cylinder would be the width of the band (40).

Therefore, to obtain greater tube lengths with the same band (40), helices (44) with smaller radius or greater angles of development "a" must be assembled. As a result, very high compaction indices can be achieved (very long appendices with relatively small reels/coils of spiral band (40)).

To reduce stresses in the material of an actual band (40) (with significant thickness) and to enable reducing the radius and allow greater lengths of the helix (44) (although with a larger number of joints), two bands (40) (or more) can be wound simultaneously: double helix (44) (triple helix, etc.).

Another possibility is to manufacture a band (40) the resting form of which is that of a corkscrew having the radius of the helix (44) to be extended, and therefore the stresses of the material of the band (40) will be greater when it is the spiral form to facilitate assembly when assembling the helix (44).

In conclusion, the relation between the length of the band (40) and the height of the helix (44) determines the degree of compaction, and as shown, very high compaction can be achieved (increasing the angle of development for arranging very high helices (44) with the same length of band (40)), and as will be shown below, with the rigidity necessary for the desired application.

Characteristics of the edges of the band (40)

The edges of the band (40) must be fastened to form the helical cylindrical tube, to that end, the upper and lower edges of the band (40) have complementary "linkable" profiles and/or teeth when they are placed facing one another. A visual image thereof can be formed by a band (40) the two sides of which are notched in the form of a zipper (although the edge does not necessarily have to have teeth). The band (40) and the teeth on its edges can be integral and rigid, although with the flexibility characteristic of the material from which they are made, which allows linking the two facing edges of the helix (44), through an engagement, hooking, linking, assembly or fastening mechanism described below. Helical assembly topology for assembling a cylinder

This description is optional because there may be a need to have a flexible tube (for example, fabric tube) formed from a band (40) with commonly used zippers on its two edges, which can be fastened or unfastened completely by hand for assembling or disassembling a tube (for example, for transporting and protecting rolled-up documents). If there is a need to have a tube with greater rigidity characteristics, the following description applies.

To form a rigid tube, the disassembled position of the helix (44) is actually quasi-disassembled because one of the ends of the appendix will normally be assembled (it is a helix (44)) and cannot be disassembled. The assembly process consists of winding a segment of band (40) additional to the initial bit, forming the seed of the appendix.

In the initial state in which only the tip of the appendix is assembled as a helix (44), the rest of the band (40) is wound and retracted in spiral around the imaginary axis of the helix (44). In the opposite state, in which the entire band (40) is assembled in a helix form (44), a small segment of band (40), which is not assembled, remains at one end of the helix (44), which is still a spiral. This small non-assembled segment will allow unwinding the helix (44) and returning it to the circular spiral form progressively in the disassembly process. In conclusion, any configuration of the automatically assembled rigid appendix is formed by a helix (44) and a spiral in different degrees of development and the mechanism for assembly and disassembly consists of the change from a spiral to a helix (44) and from a helix (44) to a spiral, respectively. For assembling the helix (44), the edge of the spiral band (40) is fastened with the corresponding edge of the existing helix (44) (the helix (44) growing gradually at the expense of the spiral). To disassemble the helix (44), the edge of the helix (44) is unfastened and the band (40) released in the existing spiral (the spiral growing gradually at the expense the helix (44) is wound). Mechanism for assembling the cylindrical tube

This element is optional and only applies if the tube is mechanically assembled and is rigid enough. For mechanically assembling the helix (44) to the detriment of the spiral (45), the band (40) can be inserted in a rotary part, hereinafter referred to as a rotary bending nut (46), which drives, by means of rotation and guides, the edge of the spiral band (40) towards the corresponding edge of the helix (44), linking them (i.e., fastening the zipper), pushing the new segment of helix (44) outwards (for example, downwards). If the rotary bending nut (46) rotates in the opposite direction, it separates the edge of the helix (44) from the corresponding edge of the spiral band (40), feeding the spiral reel/coil and reducing the length of the helical appendix (unfastening the zipper). The rotary bending nut (46) can be rotated by manually actuating a crank engaged with cogwheels with the rotary bending nut (46), or it can be rotated automatically. Therefore, the helix (44) is assembled by rotating the crank in one direction, and disassembled by rotating the crank in the opposite direction up to the stops at the two ends of the band (40). When the appendix has reached the desired length, the rotation of the rotary bending nut (46) is blocked to keep the helix (44) stable and rigid by means of an optional blocking brake (58) that adds rigidity to the assembly because it compresses the helix (44) in the rotary bending nut (46) (against its inner part or outer part).

Levels (electronic or non-electronic) can be arranged in the platform actuating the appendix to facilitate orientation thereof with respect to the direction of the force of gravity.

Mechanization/motorization of the mechanism for automatic assembly of the cylindrical tube

In a desired case, the rigid tube assembly can be motorized. To that end, a motor/engine can be coupled to the cogwheel of the rotary bending nut (46) replacing or complementing the crank. Therefore, by actuating motor rotation control in one direction, in the opposite direction and by stopping it, the helix (44) can be assembled, disassembled and blocked (maintaining the cylinder without rotation).

Evidently, several of these mechanisms, which take advantage of the compaction feature of the invention, can be combined to generate an actuation/support group to solve more complex applications.

Additionally, the appendix can be equipped with a servomechanism which allows controlling the extension of the helix (44) or appendix, for example, using the information of the signals from the electronic levels, to orient the actuated platform when a group of actuators has been arranged according to the programmed setpoint.

Several embodiments of the invention will be described briefly below as an illustrative and non- limiting example of the invention.

In relation to the drawings, three embodiments of compactable tubes (although there can be a large number of embodiments) will be described with different constructive features and technical solutions, conferring them different properties and making them more suitable for different uses and applications.

The first embodiment corresponds to a flexible band (40) with a zipper and a sliding slider, the second embodiment corresponds to a semi-rigid band (40) also with a zipper assembled in a rotary bending nut (46) with a slider and the third embodiment corresponds to a semi-rigid band (40), where the attachment is not by a zipper but rather by complementary profiles.

In the case of the first embodiment by means of a flexible band (40) with a zipper, the material of the band (40) is flexible (fabric, elastic, plastic, etc.) and the band (40) has on its edges teeth (42) similar to those of commonly used zippers (zippers having metal or plastic teeth comprising two fabric bands (40), each of them with a single notched edge linking with the opposite edge). This embodiment will have a sliding slider (48) or carriage at each contact edge (one if it is a single band (40), two if there are two bands (40)). The relative movement between the slider or the sliders (48) and the band (40) or bands (40) causes the assembly or disassembly of the appendix or helix (44), according to the direction. The technology and industrial assembly lines for this embodiment exist because the technical solution is very similar to that of zippers used in the textile industry. It only differs in that the two sides of the band (40) have zipper teeth forming a tube such as that shown in Figure 4. In this embodiment, the resulting tube is very flexible (because the band is flexible and there is play between the teeth) so use thereof must be dedicated to those applications where flexibility is not a drawback but an advantage.

To increase rigidity, the second embodiment is proposed where the band (40) of Figure 7 (having a length "L" and height or width "A") has zipper teeth (42) which are located on complementary edges (51 ) and protected and concealed in the inner part of an L-shaped upper rib which serves as a hook to increase the leak-tightness and rigidity of the resulting joint. As can be seen, the upper rib has a width less than the width of the band (40), and the joint will be seen from the outside as a smooth line (without teeth) tracing a helix (44) in the resulting tube (internally and externally). This band (40) can have a neck (52) so that the slider (48) can guide the edges along the correct path for fastening/unfastening (the neck (52) can be notched to facilitate driving the band (40) like a chain, since a large actuation force may be necessary when the tube works as part of a linear actuator under traction or compression, so the band (40) may need a notched neck (52) and the screw of the rotary bending nut (46) must also be notched so that the crank or motor transmit all the force necessary to assemble the helix (44) by pushing the free end thereof).

Figures 7B and 7D show the edges in detail, and it is shown how the teeth (42) have convex and concave elements (53, 54) for assuring attachment, like zippers. Figure 7C shows how the attachment looks like once fastened and the direction of the force that it must withstand (the arrow of Figure 7C). Figure 7D shows the contour of the non-coplanar sliding slider (48) at the height of the section where the two edges of the teeth are assembled by means of their concave and convex elements (54, 53). In this case, the left band (40) is of a lower position and the right band (40) is internally fed with respect to the tube and comes from a higher position. The non- coplanar sliding slider (48) is responsible for aligning both rows of teeth in order to fasten them. Figure 8 shows a plan view of a rotary bending nut (46) formed by a screw (49), a non-coplanar sliding slider (48) fastening the edges of a band (40) in a helix (44) with a radius "R". The band (40) in Figure 8 is fed from the outside with respect to the tube. The band (40) which is already assembled in the helix (44) shows its upper edge and the band (40) feeding the slider (which has greater circumference) shows its lower edge.

Figure 9 shows the same plan view but the rotary bending nut (46) has a non-coplanar bearing slider (48) in order to generate the helix (44) of radius "R". This slider (48) is made with cogwheels (55, 55') assembled on a support and guides and drives the band (40) like a drive chain using the teeth (42) of the band (40) like chain links. The wheels (55, 55') of the slider (48) guide the edge which is in the upper level of the band (40) feeding the helix (44) whereas the wheel (55') of the slider guides the edge of the band (40) which already forms part of the helix (44) determining its circular path (therefore only one wheel is needed). Both levels combine so that the edges are joined together, but the edge of the turn of the band (40) is below the edge of the turn of the band (40) of the spiral (naturally, in the configuration of this Figure 9). The cogwheels (55, 55') use the neck (52) of the edges for assuring correct guiding of the teeth towards the opposite edge.

A non-coplanar bearing slider (48) has been arranged in Figure 9 to improve mobility and reduce operational stress of the band (40) within the rotary bending nut (46), and in a similar manner, the screw (49) guiding the band (40) in helix form (44) can also be provided with wheels converting the entire helical channel into a bearing conduit that minimizes the work for bending the band (40), and therefore energy consumption for operation thereof. The band (40) and the wheels of the screw can be notched so that they act like a chain and pinion and achieve more precise and controlled driving of the traction during operation (of the crank or the motor).

For this embodiment the mechanism referred to as a rotary bending nut (46) will be applied for guiding the band (40) from the spiral form (45) of the initial reel/coil to the helix form (44) of the final tube (the rotation of the rotary bending nut (46) causes the assembly/disassembly of the tube without it having to rotate). The rotary bending nut (46) can be formed by a screw (49) (that gradually transforms the spiral into helix (44)) and a slider (48) for fastening/unfastening the zipper changing the plane of one of the edges of the band (40) (as shown in Figure 6). The rotation of the rotary bending nut (46) gradually leads to new band (40) entering the slider (48) for being joined to the already formed helix (44), elongating it. Unlike a conventional zipper, where the two edges and slider are located and operate in the same plane (coplanar), the new band (40) will usually enter from a different plane (non-coplanar). This slider has two ramps matching the heads of the teeth of the edges in an alternating manner with the suitable angle to produce fastening. The slider (48) comprises two holes (71 ) from which there emerge two guides (72) having a C- shaped section, with opposite openings of different inclination and converging in a single outlet (73) where they are arranged adjacent to one another without a gap therebetween. Therefore, the gap (74) ends before the outlet (73), as in the central view of Figure 6. The rotary bending nut (46) will also comprise a butt (56) against which the screws rotate (or one of them), said butt (56) withstanding the push of the helix (44) or tube as it is being formed and the weight of the structure when it is supported as a support, exerts force as a linear actuator, etc. In this embodiment, the rotary bending nut (46) can use a non-coplanar sliding slider (48) (Figure 6) internally for fastening or unfastening the band (40) forming the cylindrical helix (44) depending on the direction of rotation. This slider (48) has two ramps matching the heads of the teeth of the edges in an alternating manner with the angle suitable to produce fastening. Figure 6 shows different views of the slider in order to explain its structure and viability. The ramps of the slider can be curved in order to reduce stresses of the band (40) and to guide it in precise paths, and therefore reduce the forces necessary for manual or motorized fastening, and as a result minimize energy consumption necessary for operation thereof.

Figure 10 shows a perspective view of the rotary bending nut (46) assembling a tube from a spiral (45) or reel/coil of band (40) perpendicular to the axis of the helix (44). Therefore, the rotary bending nut (46) converts the circular spiral into a cylindrical helix (44) through a conical helical path. As a result, the inner screw (49'), the outer screw (49) and the non-coplanar sliding slider (48) are arranged to generate this conical helical path. Figure 10 also shows the butt (56) that withstands the thrust of the screw (49) overcoming the stresses of the band (40) as the tube or helix (44) is being assembled, and an end cover (57) of the helix (44) which is always assembled, a blocking brake (58) compressing/decompressing the band (40) against the outer screw (49) or inner screw (49'), and a tension cable (59) with a lock latch/ratchet/dog (70) for tightening or loosening. The cable can be replaced by a luminous wire, for example, an electroluminescent wire, for use in extendable lighting. Where appropriate, the cover (57) can comprise a lens with or without a set of mirrors for using the helix (44) thus assembled as a telescope or periscope.

The manual or motorized rotation of a cogwheel (47) acts on teeth of the rotary bending nut (46) to rotate the screw (49) and slider (48), assembling or disassembling the helix (44).

This concept is applicable to conventional zippers, i.e., by means of the non-coplanar slider it is possible to have zippers such as those currently used but without the bands (40) having to be fabric bands but rather of the same material as the teeth and integral therewith (plastics or metals). Much more robust closures for fastening, for example, metal sheets or plastic plates, can be achieved. The third embodiment relates to a tube formed from a semi-rigid band (40) (it must be able to be wound, rotated and bent/twisted) with profiled edges (with or without notches) and with a complementary joint. In this embodiment, the edges of the band (40) have complementary profiles (60) (with or without notches) assembling a completely solid and leak-tight joint (without gaps therebetween) which is reinforced with the pressure of the weight that is withstood by the form, orientation and arrangement of the profiles thereof (Figure 12).

In this embodiment, the rotary bending nut (46) guides the two complementary edges of the band (40) and arranges them so that they face one another, by means of rotation on the pivot (61 ), assembling them (by means of a rod (62)) and closing the joint, and therefore assembling the helix (44). By rotating in the opposite direction, the profiles disengage, the joint opens and the helix (44) disassembles.

For this embodiment, the band (40) can be manufactured by extrusion or the edges of the band (40) (metal, plastic, etc.) must be machined to provide them with the complementary profiles that allow forming the leak-tight joint. In the configuration of Figure 12A, the band (40) can be generated by extrusion and can be obtained in a spool or coil form, with the radius of curvature of the cylinder that will give rise to the tube (to minimize the energy necessary for assembling and disassembling the helix (44)). In Figure 1 1 A, the pivot (61 ) is the point around which progressive rotation and bending/twisting of the band (40) occur, as shown in the sequence in Figure 1 1 B (when it is necessary as a result of the chosen angle (63), to successfully engage the two complementary profiles (60) and assemble the helix (44)). The rod (62) with the suitable curvature for the rotation of the assembly on the pivot (61 ) anchors the two complementary profiles (60) and prevents the helix (44) from disassembling unless an identical bending/twisting in a direction opposite that used for assembling same occurs. The chosen angle (63) performs the function of tightening the band (40) due to the load supported by the tube against the arc of the turns of the helix (44) and counteracting the possible pressure exerted by the band (40) through hardening (if hardened strip is used as the material of the band (40)) and the larger circumference of the turns in spiral state. Like in the preceding embodiment, a neck (52) can be defined to allow gripping and guiding the band (40) through the slider. Figure 1 1 A shows the edges assembled in the wall of the cylinder.

Figure 12 shows another profile that does not require twisting for being assembled inside the rotary bending nut (46). It has a pivot (61 ), a rod (62), and a pressure angle (64). In the inner gap of the band (40), running along the entire length thereof and between the necks (52), there can be arranged a tape (65) made of an electroactive material (such as that described in patent US 6882086 B2), for example, having variable rigidity/stiffness, thus generating a combined band (40), to increase the radial pressure inside the cylinder once assembled, by means of an electric drive, and to achieve greater rigidity of the final tube and increase leak-tight pressure. When the tube is to be disassembled, the rigidity of the electroactive material would first be electrically reduced (the radial pressure towards the outside of the tube would be reduced), and then the tube would be gathered in a spiral. Figure 12 also shows a section of the tube or helix (44) formed by the assembly of the band (40) with this profile.

Figure 13A, 13B and 13C show a front view, side view and perspective view of the band (40) in the transition from a spiral to a cylindrical helix (44) (going through a conical helix (44)) or the path that it must follow within a rotary bending nut (46) such as that shown in Figure 14. Figure 14 shows a bearing rotary bending nut (46) with the opening for the inlet (66) of band (40) and the outlet (67) for the assembled helix (44), and which contains the slider and the inner screw and outer screw formed from the path and arrangement of the cylindrical bearings (68). Figure 15A shows a section of this rotary bending nut (46), Figure 15A, in the core of which runs the path shown in Figure 13 and which therefore contains the non-coplanar curved bearing slider (48) and the outer and inner screws that will assemble the band (40) of Figure 12 to cause bending and necessary movements for engaging the profiles in the closure path by rotating on the pivot. However, given the configuration of the profiles and the already assembled segment of the helix (44), the band (40) is self-guided from the spiral (45) to the helix (44) because the pivot of the assembled band (40) acts as a guide (by simply arranging ledges in the assembled band (40) until the slider makes a complete turn and the above assembled band (40) holds what was assembled in the preceding turn). Figure 15A shows the outlet (67) of the tube, the inlet (66) of the band (40), the outer cylindrical bearings (68) supporting the pressure of the outer face of the band (40) comprised in spirals (forming the outer screw of the rotary bending nut (46)) and the inner cylindrical bearings (69) (forming the inner screw (49') of the rotary bending nut (46)) guiding the core of the band (40) through the path of assembly. The combination of both types of bearings and their arrangement form the non-coplanar bearing slider (48). Figure 15B shows a plan view of the rotary bending nut (46) where the arrangement of the bearings for guiding the band (40) through the conical helix required for assembly thereof is seen. The outlet (67) of the tube or helix (44), the inlet (66) of the band (40), the outer cylindrical bearing (68) and inner cylindrical bearing (69) are seen. With this configuration, when the helix (44) is assembled, the band (40) is screwed and aligned forming the cylinder or helix (44) of the tube, so it prevents the profiles from rotating on the pivot and therefore blocks disassembling the structure in any way, which confers great robustness against pressures and longitudinal or transverse stresses with respect to the axis of the tube. In this embodiment there is no space between the two edges, and furthermore the faces of the profile can be coated with a layer of flexible material that allows the edge to be leak-tight under pressure. Therefore, very rigid and leak-tight appendices that would enable more demanding applications than in the preceding embodiment would be obtained. Figure 16 shows an arrangement of the spiral (45), spool, reel or coil of band (40) oblique (with the same angle with which the helix (44) is wound) to the axis of the helix (44) being formed. Therefore, the rotary bending nut (46) will have a cylindrical screw that is easier to make and that will prevent stresses in the band (40), so less energy will be consumed in operation thereof. However, the dimensions of the final device will be greater than in the configuration of Figure 17.

In Figure 17, the reel, spool or coil of the band (40) is perpendicular to the tube or helix (44), which minimizes the dimensions of the device but makes the rotary bending nut form (46) more complex. The screw of the rotary bending nut (46) must have a conical helical form to guide the spiral of the reel of band (40) into the cylindrical helix (44) of the tube.

In these descriptions the spiral of the reel of band (40) has been shown in a concentric position with respect to the axis of the cylindrical helix (44) of the tube. In some applications, it will be more suitable for the reel to be eccentric or external (for example, when several reels are used to form several helices (44) forming a support or actuation group, and the reels of bands (40) can be stacked to take up a single cylindrical space, tangentially feeding the helices (44)).

Claims

1 - A compactable tube characterized in that it comprises a band (40) that can be wound into a helix form (44) or cylindrical tube, having on the longitudinal edges thereof and in the direction parallel to the plane of the band (40) zipper teeth (42) for fixing one edge with the opposite edge and a slider (48) for assembling or disassembling the tube or helix (44).

2- The compactable tube according to the preceding claim, where the teeth (42) are part of complementary edges (51 ) and are arranged in the inner part of an upper L-shaped rib having a width less than the width of the band (40).

3- The compactable tube according to any of the preceding claims, where the band (40) comprises a longitudinal neck (52) close to the teeth (42) for being guided by the slider. 4- The compactable tube according to any of the preceding claims, having the band (40) not wound into a spiral (45) or reel, oblique to the helix (44), with the angle of development a of the helix (44).

5- The compactable tube according to any of the preceding claims, comprising a cover (57) in at least one end of the helix (44).

6- The compactable tube according to any of the preceding claims, comprising a rotary bending nut (46) where the band (40) is inserted and which in the rotation thereof assembles the edge of the band (40) on the corresponding edge of the helix (44), or disassembles it therefrom, by means of the slider (48).

7- The compactable tube according to claim 6, comprising an outer screw (49) and an inner screw (49') for guiding the band (40) for assembling/disassembling it. 8- The compactable tube according to claim 7, comprising a blocking brake (58) for blocking the band (40) against the outer screw (49) or inner screw (49').

9- The compactable tube according to any of claims 7 or 8, comprising outer bearings (68) and inner bearings (69) forming the inner screw (49') and outer screw (49), respectively.

10- The compactable tube according to any of claims 7 to 9, where the slider (48) comprises a series of cogwheels (55, 55') for driving and linking the bands (40) by the teeth (42).

1 1 - The compactable tube according to any of the preceding claims, which band (40) comprises electroactive tape having variable rigidity/stiffness.

12- The compactable tube according to any of the preceding claims, comprising a tension cable (59) between the ends of the helix (44).

13- The compactable tube according to any of the preceding claims, which has complementary profiles instead of zipper teeth (42), a first U-shaped profile with a curved central hole and a pivot (61 ) and a second profile with a rod (62), such that the support and rotation of the second profile on the first profile through the pivot introduces the rod into the central hole.

14- Use of the compactable tube of any of claims 1 to 13 as a telescope, periscope, tripod, toy, tool handle, drill column, walking stick, mast, linear actuator, document cover, telescopic support or strut or in extendable lighting. 15- A slider for use in a compactable tube according to any of claims 1 to 14, comprising two holes (71 ), from which there emerge two non-coplanar guides (72) having a C-shaped section, with opposite openings of different inclination and converging in a single outlet (73) where they are arranged adjacent to one another without a gap therebetween.