The invention relates to a kite and a wing rig with an inflatable support structure in accordance with the preamble of claim 1.
Conventional kites provided for kite surfing or kite land boarding are either designed as tube kites or as mats comprising chambers adapted to be filled by inflow. Tube kites have the great advantage in kite surfing that they float in the case of a fall and may thus be relaunched without major problems. In the case of the above-mentioned “mats” the pressure chambers may fill with water, so that only experienced users will succeed in relaunching.
The construction common with tube kites consists in that a support structure consisting of a front tube—in the following called leading edge—and struts positioned transversely thereto is formed of a robust Dacron® skin surrounding a bladder consisting of a thin, air-tight material which is protected from damage by the comparatively robust outer skin.
Such kites are, for instance, disclosed in U.S. 2006/0192055 A1 or DE 202 01 924 U1. In DE 10 2016 113 858 B4 by the applicant it is proposed to integrate the struts exchangeably in the support structure, so that, in the case of damage of a strut, for instance, in the case of a fall or in the case of excessive inflating, easy repair by exchanging of the struts is possible.
Depending on the field of use, tube kites have a varying number of struts. Light wind kites are, for minimizing their weight, designed with comparatively few struts, whereas race or freeride kites for which the profile is to be kept stable even at high driving speeds are designed with a plurality of struts. The light wind kite Mono® distributed by the applicant has merely one center strut, whereas the Freeridekite Rebel® is designed with five struts, i.e. one center strut, two quarter struts, and two tip struts.
The kites are offered with different sizes so as to enable an adaptation to various wind strengths. Attempts have been made to design the kite as light as possible, but with a sufficiently stiff support structure, so that the respective wind power can be transformed effectively to propulsion or uplift.
The basic setup of a generic wing rig is described in DE 10 2019 101 656.8.
Accordingly, it is an object of the invention to provide a light kite and a light wing rig with sufficient stability.
This object is solved by a kite and/or a wing rig with the features of claim 1.
Advantageous further developments of the invention are the subject matter of the subclaims.
The kite in accordance with the invention is designed as a tube kite with an inflatable support structure which comprises a leading edge (front tube) and at least one (transverse) strut attached thereto and which puts up a canopy. The wing rig is of corresponding construction. In accordance with the invention at least a partial region of the outer skin of a strut is manufactured of a different material, preferably a lighter material with a lower area weight, than the material of the outer skin of the leading edge or of other struts. This enables to design at least one strut with a reduced weight, so that, especially in the case of kites with a plurality of struts, the total weight of the kite can be reduced distinctly as compared to conventional solutions where the struts and the leading edge consist of the same, comparatively heavy material.
The term “material” means preferably the material of which the outer skin enclosing the bladder is manufactured—possibly provided reinforcements in the transition region to the leading edge or at the trailing edge-side ends of the struts as well as at front regions of the leading edge which are endangered in the case of an unintended fall of the kite shall preferably not be summarized by the term “material”.
In a particularly preferred embodiment the support structure comprises a plurality of struts whose material is, for optimizing the stiffness of the support structure, made of materials with different area weights. For improving the stability of the support structure it is, for instance, possible that a center strut is made of a material having an area weight higher than that of external struts.
In the case of a kite designed with five struts, for instance, the center strut and the two adjacent quarter struts may be manufactured of a comparatively heavy material, whereas the tip struts are manufactured of a particularly light material.
In one embodiment of the invention the center strut is manufactured of the same material as the leading edge.
In accordance with the invention it is particularly preferred if the heavier material which is, for instance, used in regions of the leading edge and for the center strut, has an area weight of more than 120 g/m2, preferably more than 130 g/m2, and the light material has an area weight of less than 100 g/m2, preferably less than 90 g/m2.
The heavier material may be the conventionally used Dacron®, the light material may be a material which is commonly used for the canopy or in sailing for spinnakers (spinnaker material).
Cloths on a polyester basis or the particularly light cloth Aluula® have turned out to be particularly suited materials.
The stiffness/elasticity of the strut can be optimized further if portions of the strut are made of the heavier material, so that, for instance, the strut toward the trailing edge is made of the lighter material—accordingly, the strut is, in the binding region to the leading edge, designed to be comparatively stable/stiff, whereas the trailing edge-side end portions are designed to be flexible and thus enable better navigating and a more dynamic handling.
In other words, the comparatively stiff material with a high area weight forms the leading edge-side portion of the strut, whereas the trailing edge-side portion is made of a softer, flexible material.
The applicant reserves the right to direct an own independent claim to a support structure in which, for the strut(s) or the leading edge, materials with different stiffness/flexibility are chosen for forming the outer skin, wherein the area weight may then take a back seat. It is to be understood that, when choosing the suitable materials, it may correspondingly be taken care that the lighter material is also appropriately designed to be more flexible and more elastic than the material with the higher area weight.
Correspondingly, the leading edge may also be formed of a material mixture consisting of a lighter material and a heavier material. Thus, it is, for instance, conceivable to design the leading edge toward the tips from a material with a lower area weight, whereas the middle region of the leading edge is made of a comparatively heavy, stiff material.
Due to the use of lighter materials for the struts/leading edge in accordance with the invention it is possible to design the support structure to be more flexible than in the case of conventional solutions, so that the flight characteristics are influenced positively. Thus, for instance, the turn-in behavior of the kite is improved by the higher flex and the acceleration in gusts/maneuvers is improved due to the low weight.
Preferred embodiments of the invention will be explained in detail in the following by means of a schematic drawing.
The only FIGURE shows a three-dimensional front view of a kite optimized for freeride use.
Such a kite 1 has a support structure 2 consisting of a front tube or leading edge 4 and five transverse struts formed transversely thereto, in the following called struts 6, which put up a canopy 8 together. The filling of the leading edge 4 is performed by means of a valve (not illustrated) formed at the leading edge 4 and also enabling the filling of the struts 6 via a one-pump-system. The FIGURE illustrates the model Rebel® where five struts 6 are used. In the middle region of the leading edge 4 (front tube) a center strut 10 is provided, adjacent thereto two quarter struts 12a, 12b are provided, and for the stiffening of tips 15, 16, tip struts 14a, 14b are provided in the region thereof. As illustrated in the FIGURE, the diameter of the leading edge 4 decreases toward the two tips 15, 16. Correspondingly, the struts 6 also taper away from the leading edge 4 toward the trailing edge 18 positioned aft in the direction of inflow.
As explained above, the outer skin of the leading edge 4 and of the struts 6 is made of a comparatively wear-resistant material and surrounds a bladder (not illustrated) which may be inflated via the initially-mentioned valve. This bladder merely contributes to the air tightness of the support structure 2 and is accordingly designed with a view to the pressure strength. In the case of conventional kites the struts 6 and the leading edge 4 are—apart from the necessary reinforcements—made of Dacron®. This material is, for instance, also used for the manufacturing of sails. Such Dacron® material has usually an area weight of more than 120 g/m2.
In accordance with the invention it is provided to design the outer skin of at least portions of at least one strut 6 from a material having a lower area weight. This “lighter” material is then made with an area weight of less than 100 g/m2, preferably less than 90 g/m2, for instance. In recent times, also materials have been available in the market which have, with a strength/stiffness and wear resistance comparable to Dacron®, an area weight of approx. 70 g/m2.
Such material is, for instance, offered under the trade mark Aluula®. It is particularly preferred if the material used for the strut 6 has an area weight between 90 g/m2 and 70 g/m2, whereas the material of the outer skin of the leading edge 4 and/or the other struts 6 has an area weight between 130 g/m2 and 160 g/m2.
In the case of a kite 1 with five struts 6, for instance, the center strut 10, the leading edge 4 and possibly also the two quarter struts 12a, 12b may be manufactured of
Dacron® with a comparatively high area weight, whereas the tip struts 14a, 14b are made of a lighter material, for instance, Aluula®.
Basically, it is also possible to manufacture the quarter struts 12a, 12b from a material whose area weight ranges between that of the center strut 10 and the trip struts 14a, 14b, so that the tip region is optimized with respect to flexibility. In other words, in the middle region of the kite 1 a comparatively stiff, heavy material is used, whereas the tip regions are manufactured of a light, soft, flexible material.
As indicated in the FIGURE, a leading edge-side region A of a strut 6, for instance, the center strut 10, may be manufactured of the same material as the leading edge 18. This region A of a comparatively heavy, stiff material (Dacron®), may, for instance, extend over 10 cm to 20 cm. In the region marked with B the material is then designed with a lower area weight, so that the trailing edge-side portions of the respective struts 6 may be formed flexibly from a soft material. This enables, for instance, to design the trailing edge-side portion of the strut 6, with a low weight, with a somewhat larger diameter than with conventional solutions for optimizing stiffness.
A corresponding concept may also be provided for the leading edge 4. Thus, for instance, the middle region M of the leading edge 4 may be manufactured of the heavier material, whereas tip-side regions R are then made of a lighter material.
It is to be understood that the zones indicated in the FIGURE may also be of different design. Basically, it is also possible to design more than two regions of a strut 6 or a plurality of struts 6 with different materials. The same also applies, of course, to the leading edge 4.
In the FIGURE reference number 22 designates the regions provided with a reinforcement. This reinforcement 22 may, for instance, also be made of a heavy Dacron® material. Basically it is, however, also possible to form at least tip-side reinforcements by the doubling of lighter materials, so that sufficient protection is guaranteed with low weight.
In the Table below some materials are mentioned which are used for forming the leading edge 4 and/or the struts 6. The designations used here are well-known to the person skilled in the art.
In the case of light wind kites with one single center strut 10, for instance, (see the model Mono®, for example), this one may correspondingly be designed of a lighter material than at least partial regions of the leading edge 4. Since such light wind kites are designed with a large face and accordingly the center strut 10 is comparatively long, it is convenient to make at least portions thereof of a very light material such as, for instance, the Aluula® material, wherein, in the binding region to the leading edge 4, a stiffer, heavier material such as, for instance, one of the Dacron® materials in accordance with the above Table may be used. In the case of such a light wind kite the trailing edge 20 may then be manufactured from Dacron® throughout, or else from the afore-described material mixture.
However, the invention is by no means restricted to the use of conventional Dacron®/spinnaker materials or cloths. Basically, laminates, films, or the like which are suited for use as an outer skin of kites may also be used.
Basically, wing rigs may also be designed in the afore-described manner.
The invention relates to a support structure of a kite or wing rig, wherein portions of at least one strut are made of a material different from that of a front tube/leading edge or of another strut.
List of Reference Numbers:
1 kite
2 support structure
4 leading edge
6 strut
8 canopy
10 center strut
12 quarter strut
14 tip strut
15 tip
16 tip
18 trailing edge
22 reinforcement
Number | Date | Country | Kind |
---|---|---|---|
10 2019 129 493.2 | Oct 2019 | DE | national |
Filing Document | Filing Date | Country | Kind |
---|---|---|---|
PCT/EP2020/069734 | 7/13/2020 | WO |