WO2010053373A1

WO2010053373A1 - Foldable ramp

Info

Publication number: WO2010053373A1
Application number: PCT/NO2009/000183
Authority: WO
Inventors: Jørgen LEIRDAL; Martin Otto Fougner; Mette Mørck HELLAND
Original assignee: Flexirampe As
Priority date: 2008-11-10
Filing date: 2009-05-14
Publication date: 2010-05-14
Also published as: NO20084734A; NO328067B1

Abstract

The invention concerns a foldable ramp (1) for relocation of material between a first level of height and a second, elevated level of height. The ramp (1) is assembled by several coupling parts (2), wherein each coupling part comprises a close to rectangular transport surface (3) and two coupling links (4) oriented parallel with said transport surface (3). Each coupling link (4) comprises at least one rotation opening (10) for coupling of each coupling link (4) to at least one adjacent coupling link (4) by insertion of at least one main fixing device (11) therethrough. The ramp (1) is further characterized in that the close to rectangular transport surface (3) of each coupling part (2) comprises two layers that are closed in longitudinal and height direction, and two sides that are completely or partly open in the transversal direction. Furthermore, the coupling links (4) in each coupling part (2) overlap with the adjacent coupling link(s) (4) when connected, wherein the overlap in height direction extends from the upper, outer surface (21) of the coupling link (4), to the lower, outer surface (22) of the coupling link (4), when the ramp (1) is completely unfolded. In addition, each of the coupling links (4) is designed with at least one main recess (8) in one end of the coupling link (4) and at least one main protrusion (9) in the opposite end of the coupling link (4), and with a shape rendering alignment of the two sides of the coupling link (4) in the transversal direction with the corresponding two transversal sides of the adjacent coupling link(s) (4) possible.

Description

Foldable ramp

Technical field:

The present invention concerns a foldable ramp for relocation of material between a first level to a second, more elevated level, in which the ramp is assembled by two or more connecting parts manufactured by materials of light weight and high strength. Extension and shortening of the ramp in the longitudinal direction, as well as in transversal direction may easily be achieved by assembling and disassembling the connecting parts, respectively.

In particular, the invention concerns a ramp for relocation of objects equipped with wheels such as wheel chairs, and which is easily foldable to minimize the need for space during storage, and to ease loading, storage and unloading in connection with transport.

In addition, the invention concerns a method for assembling a foldable ramp, as disclosed in the introductory part of the independent claim 13.

Background and prior art:

Foldable ramps are used today in a variety of applications. For example is a reliable ramp (i.e. foldable by rolling) disclosed in patent application WO 03/082714 Al which may be extended both in the longitudinal and transversal direction by assembly of several connecting parts. The separate connecting parts are assembled by overlapping, hemispherical projections using bolts. However, the design of the connecting parts causes lower degree of overlapping that in the case of the present invention, and thereby lower stability. In addition, the connecting parts are designed with straight edged contacting surfaces, thereby creating danger of clamping/pinching during handling. Insertion of a separate clamping protector at the crossing between two connecting parts has in practical applications shown to not limit the risk of clamping in any significant degree. Furthermore, the transport surface of the ramp consists of only one layer, in which slots are introduced in the transport surfaces to achieve a reduced weight. Such a design limits significantly the maximum weight load of the device.

A similar ramp is disclosed in patent application US 2006/0214456 Al. Its structural design is significantly different from the ramp disclosed in patent application WO 03/082814 Al and the present invention in that each connecting part/segment is designed as a "shovel" form having to projections in the longitudinal direction. Due to a larger degree of overlapping between the separate connecting segments the lateral/transversal stability is improved compared to the solution disclosed in patent application WO 03/082714 Al . However, the simple connecting in said US application gives potential for further stability improvements, especially in height and longitudinal direction. In addition, the latter solution of a ramp causes a significant risk for clamping/pinching during handling. As in the former prior art, the transport surface of the ramp consists of only one layer, thus limiting significantly the maximum weight load.

Object of the invention

In view of the prior art, it is an object with the present invention to provide a foldable ramp as mentioned in the introduction which is easy transportable, of light weight, of high strength and high carrying capacity, and which shows high stability in height, transversal and longitudinal direction.

A more particular object with the present invention is to provide a foldable ramp that is assembled by single components, where said assembled components may easily be disassembled and reassembled. In addition, the ramp should be folded/opened by one or more users, independent or close to independent of prior obtained experiences/knowledge of the present invention, and without exposing himself and/or others for significant danger of clamping/pinching. Herein, danger of clamping signifies danger of clamping between two objects that may result in injury and/or pain, and foldable ramp signifies a ramp where user(s) may reduce the need of space of the device during storage by folding/bending/rolling the assembled components.

Summary of the invention:

Said and other objects of the present invention are achieved by a foldable ramp given in the introductory part of claim 1 and the introduction of the description, having the features stated in the characterizing clause of said claim. Corresponding objects of the present invention are achieved in a method for assembling and possible disassembling of the above described foldable ramp, having the characterizing features stated in the independent claim 13. Further advantageous embodiments of the invention are stated in the dependent claims 2-12 and 14. In particular, the present invention concerns a foldable ramp assembled by two or more connecting/coupling parts. Each connecting part comprises a rectangular or close to rectangular transport surface and two (right and left, respectively) connecting/coupling segments/links oriented parallel or close to parallel with said transport surface, where each coupling link comprises at least one rotation opening for connection of each coupling link to at least one adjacent coupling link in the longitudinal direction by insertion of at least one main fixing device through two mutually aligned rotation openings. Furthermore, the transport surface of each coupling part comprises two layers that preferably are closed in longitudinal and height direction, and two sides that preferably are completely or partly open in the transversal direction, and where the coupling links in each coupling part overlap with the adjacent coupling link(s) in a significant degree when connected. When the ramp is completely folded out said overlapping is extending in its height direction from the upper, outer surface of the coupling link, or close to the upper, outer surface of the coupling link, to the lower, outer surface of the coupling link, or close to the lower, outer surface of the coupling link. In addition, each of the coupling links is designed with at least one main recess in one end of the coupling link and at least one main protrusion in the opposite end of the coupling link, and where the at least one main recess and the at least one main protrusion are design in such a way that the two sides in the transversal direction of the coupling link are aligned or close to aligned with the corresponding two sides of the adjacent coupling link(s).

In a preferred embodiment at least one end of the at least one main fixing device is supplied with a stopping mechanism such as clip or nut to prevent that the at least one main fixing device is released unintentionally from the at least two mutually aligned rotation openings.

Inter alia, to reduce clamping danger and to form a higher degree of compactness between two coupling links, it is desirable that the at least one main recess in one end of each coupling link is designed as a recessed quarter of a circle, or close to quarter of a circle, and that the at least one main protrusion in the opposite end of the coupling link in the longitudinal direction is designed with curvature with a curvature radius that is equal to, or close to equal to, the curvature radius of the recessed quarter of a circle of the main recess belonging to the adjacent coupling link.

To further improve the stability of the ramp in the transversal, height and longitudinal direction each coupling link in a particular embodiment has been designed with an end that comprises at least two curvature designed, parallel arranged, main protrusions having identical or close to identical curvature radii. The at least two protrusions have each at least one rotation openings with identical positions in height and longitudinal direction.

To avoid unintentional folding of the ramp, it is desirable that each coupling link has at least one stopping mechanism that is integrated in the at least one main recess of the link. Such a mechanism prevents folding of the ramp in one of two folding directions when the ramp is completely unfolded, resulting in that the ramp may only be rolled up when reduction of the space is desired without disassembling the ramp.

To assure a certain folding resistance in the folding direction, for example when the ramp is completely unfolded, the at least one main protrusion in each coupling link may be designed with at least one secondary protrusion located at one of the transversal side of the link, and the at least one main recess in the at least one adjacent coupling link has at least one secondary recess located on the transversal side opposite of said transversal side of the coupling link having said secondary protrusion, where the at least one secondary recess is arranged in the same position as the at least one secondary protrusion when the ramp is completely unfolded and/or arranged in the same position when the ramp is completely or partly folded. It is obvious for a skilled person in the field that identical result is achieved when the placement of the at least one secondary protrusion and the at least one secondary recess are interchanged for every pair of coupling link and adjacent coupling link.

It is also desirable that the structures of the transversal sides of the coupling links which are facing inward to the respective transversal sides of the transport surfaces, and the structures to the latter transversal sides, are designed in such a way as to be mutually connectable by simple displacement in the transversal direction. For example, the structure of the coupling links in the transversal direction may form a tight fit connection with the transversal sides of the transport surfaces. The width of the ramp according to the invention may be extended by assembling of more transport surfaces in the transversal direction by for example the same tight fit connection as mentioned above. An additional coupling between each coupling link and the respective transport surfaces, and possible between the adjacent transport surfaces in the transverse direction, may be achieved by application of at least one, preferably two, secondary fixing devices on each coupling link. Examples of secondary fixing devices are bolt or threaded screw.

If the ramp is used for humans such as pedestrians and/or wheelchair users, the load carrying capacity of the ramp should be minimum 4-500 kg. When manufacturing the above described coupling links any material may be used that exhibit the material properties that provide the sufficient strength to carry the materials which should be transported. However, it is desirable to use one or more non-metallic materials, such s non-metallic composite materials with a certain amount of fiberglass. The purpose of the fiberglass would, in the latter case, be to increase the properties of the material in the form of higher load carrying capacity.

An additional advantageous embodiment is to supply the upper part of each coupling link in the ramp at least one third recess to facilitate ease connection of at least one holder for at least one additional object. Such additional objects may for example comprise security devices such as railings. It is also desirable that at manufacture a separate fixing device is mounted on the ramp to facilitate coupling of the ramp, preferably in completely or partially folded position, to an object. The object may for example comprise a vehicle in connection with transport of the ramp and/or storage at a more permanent storage space, such as suspension above ground level. A further, advantageous embodiment is to prepare the ramp for mounting of auxiliary equipment, preferably at the lower part of each coupling link, such as stabilizing rods mounted underneath one or more transport surfaces and fastened to its or theirs respective coupling link(s). Such stabilizing rods may also be used as fixing devices for storage and/or transport of the ramps.

As specified in the introduction of the description the present invention concerns relocation of any material between a first level and a second, high level. However, the ramp is particularly suited for relocation of objects suited for transport such as pedestrians and/or wheel equipped objects. A specific example of the latter object is wheelchair.

To ease the entrance and exit of objects on the ramp, in particular for entrance/loading of wheel equipped objects, one or both ends of the ramp is/are in an embodiment equipped with at least one end piece extending from the base of the ramp in the respective levels. An example of design of such an end piece may be a wedge formed end piece.

The assembly of the above described foldable ramp according to the present invention may be implemented by a method comprising the following steps:

- assembly of one coupling part comprising a rectangular or close to rectangular transport surface and two coupling links by

- adjusting the position of each coupling link such that the structure design in one of the transversal side of each coupling link has same or close to same position in height and longitudinal direction as the corresponding and coincident structure design of the adjacent transversal side of the transport surface,

- displace each of the two coupling links towards theirs respective transversal sides in the transport surface so that the structure design of the transport surface interconnects with the structure design of the coupling links,

- interconnecting two or more coupling parts by adjusting their relative positions such that at least one rotation opening inserted in each coupling link is located in identical position as the opposite located rotation opening of the adjacent coupling link, and inserting at least one main fixing device in the at least two mutually aligned rotation openings belonging to the two adjacent coupling links to be connected,

- possibly mounting at least one second stopping mechanism, for example clamp or clip, in or around at least one of the two ends of the main fixing device(s) to prevent that the main fixing device(s) is/are released unintentionally from the rotation opening(s) - possibly fastening additionally at least one secondary fixing device, such as bolt or screw, to each coupling link and their respective transport surfaces to provide stronger connection/coupling between each transport surface and their respective two coupling links,

- possibly mounting at least one security device to at least one third recess located in the upper part of the at least one of the two transversal sides of the coupling link for all or some of the coupling parts,

- possibly mounting at least one end piece on one or both ends of the ramp.

Likewise, disconnecting/disassembly of the same foldable ramp may take place by the following steps:

- possibly demounting the at least one end piece from one or both ends of the ramp,

- possibly demounting of the at least one security device from the at least one third recess located in the upper part of the at least one of the two transversal sides of the coupling link for all or some of the coupling parts,

- possibly removing the at least one secondary fixing device connecting each transport surface to their respective two coupling links,

- possibly demounting the at least one second stopping mechanism from the at least one of the two ends of each main fixing device, - pulling out the main fixing device(s) from the two aligned rotation openings belonging to each of the adjacent coupling links interconnected so that the two or more coupling parts are disconnected,

- demounting each of the one or more coupling parts by sliding each coupling link out of their respective said transport surface in the transversal direction. Short description of the drawings

The invention will be further described below in connection with exemplary embodiments with reference to the drawings, where figure 1 illustrates in perspective the inventive ramp, figure 2 shows the inventive ramp in assembled and folded state, figure 3 shows a part of the ramp, in which one coupling link is removed, figure 4 shows in perspective a part of the ramp in folded state, figure 5 illustrates in perspective the ramp shown in figure 3 seen from underneath, figure 6 illustrates in perspective an exploded view of one coupling part and figure 7 shows schematically a sectional drawing of four assembled coupling links.

Detailed description of embodiments

Figures 1 and 2 show an assembled ramp 1 according to the invention in unfolded and folded state, respectively. The ramp 1 is assembled by eight coupling parts 2, in which each coupling part 2 comprises one transport surface 3 having two coupling links 4 arranged on the transversal sides of the transport surface 3. An end piece 5 in shape of a hollow wedge is shown in figure 1, located at each longitudinal end of the ramp 1, to ease the entrance/exit of for example wheelchairs. The coordinate system 6 at the left of the ramp 1 in figure 1 specifies transversal, longitudinal and height directions of the ramp 1.

Figure 3 shows in perspective an end of the ramp 1 according to the invention, in which four coupling parts 2 are assembled except one omitted coupling link 4. As shown in the area at the omitted coupling link 4 the inner part of the transport surface 3 is designed with several cavities 7 which in this example extend across the transversal sides of the transport surface 3. Such a structure of cavities 7 results in high strength / high load carrying capacity, while reduces the total weight of the ramp 1.

As shown in figure 3 an end of each coupling link 4 is designed with at least one recess, called main recess 8, in shape of a recessed quarter circle, and with a curvature designed protrusion, called main protrusion 9, in the end of the link 4. The curvature radius of the main protrusion 9 is preferably equal to the curvature radius of the main recess 8 of the adjacent coupling link 4. In each coupling link 4 two rotation openings 10 are inserted, in which the rotation opening 10 in each end is aligned in longitudinal and height direction with the rotation opening 10 of the adjacent coupling link 4. The transversal sides of the two coupling links 4 at their overlapping areas are arranged surface to surface. By guiding a suitable fixing device, herein called main fixing device 1 1, inside the two mutually aligned rotation openings 10, the desired foldable coupling between the coupling links 4 is obtained. In all of the figures bolts are used as main fixing devices 11. However, also other elongated fixing devices may be used.

To increase the stability of the ramp 1 in unfolded and possibly folded state, a secondary recess 12 with accompanying secondary protrusion 13 are inserted in each coupling link 4. A secondary recess 12 is shown by arrow in figure 3 and further illustrated in figure 4. In figure 4 two circular frames are inserted showing in details those parts of the coupling link 4 in which secondary recess and/or secondary protrusion 13 are inserted. For each secondary recess 12 in a coupling link preferably at least one corresponding secondary protrusion 13 exist located in the opposite end of the adjacent coupling link 4, and position in such a way so that the secondary protrusion 13 may slip in to the secondary recess 12 at desired folding degree(s) of the ramp 1. Furthermore, it is considered advantageous that there are provided at least two secondary recesses 12 in each coupling link 4 having corresponding at least two secondary protrusions 13 in the adjacent coupling link 4.

The different coupling links 4 are fastened / coupled to their respective transport surfaces 3 by using the above mentioned structure of cavities 7 in the transverse sides of the transport surfaces 3. By adjusting the structure design of each of the transversal sides of the coupling link 4 facing inwards to their respective transversal sides of the transport surface 3 a steady adaption may be achieved, and consequently a steady coupling between the coupling links 4 and the transport surfaces 3. Examples of such a coupling are shown in figures 2-4, and further illustrated in figure 7.

To further strengthen said couplings also secondary fixing devices 14 such as screws are preferably used. In the embodiment according to the invention the two outermost cavities 7 in the transport surface 3 are manufactured / designed with recipients 15 for said secondary fixing devices 14. One of these recipients 15 are shown in figure 3 in the shape of a clip formed channel, preferably manufactured with threads (see also figure 7). All the figures show the location of suitable holes 16 for secondary fixing devices 14 on their respective coupling links 4.

Figure 5 shows in perspective the ramp 1 in figure 3, seen from underneath. A rod, herein called stabilizing rod 17, underneath the transport surface 3 is shown extending from one coupling link 4 to the other coupling link 4 accompanying the same transport surface 3. Such a stabilizing rod 17 results in a further stabilization of each coupling part 2, and gives the opportunity to fasten the ramp 1 onto different objects in connection with for example storage or transport of the ramp 1. Figure 6 illustrates in perspective an exploded view of one coupling part 2 in accordance with the invention, comprising two coupling links 4 arranged on each side of the transport surface 3 of the coupling part 2, and shows suggested locations of the preferably two rotation openings 10 in each coupling link 4, in addition to at least one main fixing device 11 and at least one secondary fixing device 12 of each rotation opening 10.

In addition, a stopping mechanism is shown in figure 6, herein called second stopping mechanism 18, in the shape of a clip and connected to an end of the main fixing device / the bold 11. The purpose of this second stopping mechanism 18 is to prevent that the main fixing device(s) 1 1 unintentionally is/are released from the rotation openings 10.

Figure 7 shows schematically a sectional drawing of four assembled and unfolded coupling links 4 and transport surfaces 3, in which exemplary structural designs of the transversal sides of the transport surfaces 3 and the coupling links 4 are shown with the purpose of obtaining the desired tight fit (middle arrow). In addition, positions are shown for the main fixing devices 11 (right arrow) and stopping mechanism 19 between two coupling links 4 (left arrow). The stopping mechanism, preventing further folding when the ramp 1 is in a completely unfolded state, is achieved due to the specific design of the interface between a coupling link 4 and its adjacent coupling link

4 at the upper part of the coupling links 4. By folding / rotation in the allowed direction of the ramp, the interface, i.e. the outer surfaces in the longitudinal direction between the two coupling links 4, splits apart in the upper halves of the links 4, and the lower halves of the two links 4 are partly sliding against each other (see also figure 4).

At the end of the coupling link 4 shown in figure 7 the end piece 5 for easy entrance to or exit from the ramp 1 is shown. For coupling of the end piece 5 to its coupling part 2 one of the main fixing devices 11 is herein used, possibly together with the second stopping mechanism(s) 18.

The transversal sides of the coupling links 4 facing inwards to the transversal sides of the transport surface 3 have preferably, and shown in figure 7, several recesses to reduce the weight of each coupling link 4, which also maintain the necessary strength. The upper recess of the link, herein called third recess 20, may also be used to mount extra equipments such as holders for security devices. An example of such security device is railing.

Claims

180488-TR

P a t e n t c l a i m s

' 5 1. Foldable ramp (1) for relocation of material between a first level of height and a second, elevated level of height, said ramp (1) being assembled by two or more coupling parts (2), wherein each coupling part (2) comprises a close to rectangular transport surface (3) and two coupling links (4) oriented parallel or close to parallel with said close to rectangular transport surface (3), each coupling link (4) comprises at io least one rotation opening (10) for coupling of each coupling link (4) to at least one adjacent coupling link (4) by insertion of at least one main fixing device (1 1) through two mutually aligned rotation openings ( 10), characterized in that the close to rectangular transport surface (3) of each coupling part (2) is comprises two layers that are closed in longitudinal and height direction, and two sides that are completely or partly open in the transversal direction, coupling links (4) in each coupling part (2) overlap with the adjacent coupling link(s) (4) when connected, wherein the overlap in height direction extends from the upper, outer surface

20 (21) of the coupling link (4), or close to the upper, outer surface (21) of the coupling link (4), to the lower, outer surface (22) of the coupling link (4), or close to the lower, outer surface (22) of the coupling link (4), when the ramp (1) is completely unfolded, and each of the coupling links (4) is designed with at least one main recess (8) in

2₅ one end of the coupling link (4) and at least one main protrusion (9) in the opposite end of the coupling link (4), and where the at least one main recess (8) and the at least one main protrusion (9) are designed in such a way that the two sides in the transversal direction of the coupling link (4) are aligned or close to aligned with the corresponding two transversal sides of the adjacent coupling link(s) (4).

30

2. Foldable ramp (1) according to claim 1, characterized in that at least one end of the at least one main fixing device (8) of each coupling link (4) is designed as a recessed quarter circle or close to quarter circle, and 3₅ at least one main protrusion (9) in the opposite end in the longitudinal direction of the coupling link is designed with curvature having a curvature radius that is equal to or close to equal to the curvature radius of the recessed quarter circle of the main recess (8) of the adjacent coupling link (4).

3. Foldable ramp (1) according to one of the preceding claims, characterized in that each coupling link (4) has an end that comprises at least two curvature designed, parallel arranged, main protrusions (9) with identical or close to identical curvature radii, wherein each of the at least two main protrusions (9) have at least one rotation opening (10) with identical positions in height and longitudinal direction.

4. Foldable ramp (1) according to one of the preceding claims, characterized in that each coupling link (4) has at least one stopping mechanism (19) integrated in the at least one main recess (8), wherein the at least one stopping mechanism (19) prevents folding of the ramp (1) in one of the two folding directions when the ramp (1) is completely unfolded.

5. Foldable ramp (1) according to one of the preceding claims, characterized in that the at least one main protrusion (9) in each coupling link (4) has at least one secondary protrusion (13) located at one of the transversal side of the link (4), and the at least one main recess (8) in the at least one adjacent coupling link (4) has at least one secondary recess (12) located on the transversal side, opposite of said transversal side of the coupling link (4) having said secondary protrusion (13), wherein the at least one secondary recess (12) is arranged in the same position as the at least one secondary protrusion (13) when the ramp (1) is completely unfolded and/or arranged in the same position when the ramp (1) is completely or partly folded.

6. Foldable ramp (1) according to one of the preceding claim, characterized in that each of the transversal sides of the coupling links (4) facing inwards to their respective close to rectangular transport surfaces (2) is designed so that the coupling links (4) are connectable to the adjacent transversal sides of the transport surfaces (3) by displacement.

7. Foldable ramp (1) according to claim 6, characterized in that at least one additional coupling is added between each coupling link (4) and the adjacent, close to rectangular transport surface (3) by application of at least one secondary fixing device (14) such as at least one screw.

8. Foldable ramp (1) according to one of the preceding claims, characterized in that the at least one end of the at least one main fixing device (11) is supplied with a second stopping mechanism (18) preventing the at least one main fixing device (11) to be released unintentionally from the at least two mutually aligned rotation openings (10).

9. Foldable ramp (1) according to one of the preceding claims, characterized in that 5 some or all of the coupling links (4) are adapted for mounting of additional parts such as stabilization rods (17)

10. Foldable ramp (1) according to one of the preceding claims, characterized in that each coupling link (4) is manufactured by a composite material containing fiber glass.

10

11. Foldable ramp (1) according to one of the preceding claims, characterized in that each coupling link (4) has at least one third recess (20) located in the upper part of the coupling link (4) rendering possible easy connection of at least one security device such as railing.

I ₅

12. Foldable ramp (1) according to one of the preceding claims, characterized in that the material that is relocated by use of the ramp (1) comprises objects equipped with wheels. 0

13. Method for assembly of a foldable ramp (1) for relocation of material between a first level of height and a second, elevated level of height, characterized by the following steps:

- assembly of one coupling part (2) comprising a rectangular or close to rectangular transport surface (3) and two coupling links (4) by 5 - adjusting the position of each coupling link (4) such that the structure design in one of the transversal side of each coupling link (4) has the same or close to the same position in height and longitudinal direction as the corresponding and coincident structure design of the adjacent transversal side of the transport surface (3),

- displace each of the two coupling links (4) towards each of the transversal

30 sides of the transport surface (3) so that the structure design of the transport surface (3) interconnects with the structure design of the coupling links (4),

- interconnecting two or more coupling parts (2) by adjusting their relative positions such that at least one rotation opening (10) inserted in each coupling link (4) is located in identical position in longitudinal and height direction as the at least one opposite

3₅ located rotation opening (10) of the adjacent coupling link (4), and inserting at least one main fixing device (11) in the at least two mutually aligned rotation openings (10) belonging to the two adjacent coupling links (4) to be connected.

14. Method according to claim 13, characterized by

- mounting at least one second stopping mechanism (18) in or around at least one of the two ends of the at least one main fixing device (11) to prevent that the at least one main fixing device (11) is released unintentionally from the at least two aligned rotation openings (10).