The present invention relates to an inflatable jumping pit comprising at least one inflatable structure having a set of substantially vertical poles substantially parallel to each other. Pits of this kind absorb kinetic energy of an object falling from height, and are therefore apt especially for high and pole jump events, as well as a safety fall pits.

In the international publication WO 2010/112953 the inventor of the present application disclosed a jumping pit, which comprises a flat elastic structure and a shield put thereon, where the elastic structure is an inflatable mattress provided on one side with evenly placed elastic inflatable poles attached with one side to the surface of the mattress. The poles are open from the side adjacent to the mattress and attached to the mattress along the edge of their bases so that volumes of the poles and volume of the mattress constitute the one whole. The mattress with the poles is covered from the outside, from the top and from the sides with the shield, the shape of which is aligned with the shape of the mattress and its poles and which is supported on the tops of the poles.

German utility model application DE202008014715 U1 discloses a similar air mattress provided with a number of tightly juxtaposed poles having interiors connected with the interiors of the mattress and provided with cross-sectional openings of a decreasing diameter, which differentiate load on each pole so that the surface tension of a whole mattress is reduced.

Although such jumping pits provide efficient absorbing energy of a fall from heights, a process of forming a large number of sealed connections between a base mattress and poles is labor-consuming and complicated taking into account the edges of the bottoms of the poles that need to be sewn in or otherwise air-tightly connected to the wall of a base mattress. Likeness of a lack of airtightness is also increased due to this large number of sealed connections between the poles and the mat.

Furthermore the pit disclosed in DE202008014715 U1 , while in use, needs to be continuously supplied with air by an air generator, wherein excessive air is discharged by discharge valve. The object of the present invention is to provide a jumping pit of a simple and economical construction that would be easy to fold for storage and transport occupying as less space as possible yet at the same time easy to unfold and which would feature high efficiency in absorbing energy of a fall from heights. Another object of the invention is to provide a jumping pit of a modular construction that would enable for constructing pits of various dimensions and shapes.

In order to accomplish the aforementioned and other objects, according to the present invention it is provided an inflatable jumping pit as defined in the outset the inflatable structure of which further comprises a set of substantially horizontal pipes, wherein at least two adjacent pipes are separated by and connected to at least one pole, and at least one element of the inflatable structure is provided with at least one valve for inflating and/or deflating the structure.

Preferably diameter of the pipes is smaller than the heights of the poles.

!n a jumping unit according to the invention the bottom surfaces of the pipes and the poles are preferably coplanar and the inflatable structure is covered with a shield at the top.

Alternatively the top surfaces of the pipes and the poles are coplanar. In such a case a shield may not be necessary.

Furthermore at least one pipe and at least one pole of the structure may be advantageously connected by means of adhesives, welds, seams, straps with buckles and/or Velcro fasteners.

According to the present invention it is advantageous if at least one pipe and at least one pole of the structure are connected by means of at least one connector fixed to these elements of the structure by adhesives, welds and/or seams. In such embodiments said connector is preferably a releasable connector and/or is provided with a through opening or valve.

The inflatable structure of a pit according to the invention may be preferably divided into a number of separately inflatable subspaces. Therefore the pit as a whole may still perform its energy absorbing function even in a case of puncture or loss of airtightness of one subspace, since the other subspaces shall still retain their pressure.

The jumping unit of the invention may comprise more than one segment comprising a separate inflatable structure and/or a shield.

The pipes and the poles of the inflatable structure may have a cylindrical shape, preferably of substantially the same cross-sectional diameter.

Furthermore the pipes and the poles are preferably made of a composite fabric material comprising a strong textile layer coated on both sides by polymeric, in particular elastomeric, continuous films.

The construction of the inflatable structure according to the present invention features high efficiency in absorbing energy of a fall from heights and provides secure deceleration of jumpers falling from heights without any need to be continuously supplied with air. The pit according to the present invention features low surface tension and thus lacks any bouncing characteristics fulfilling high safety requirements established for sports jumping pits. Furthermore the pit has a relatively low height and segments thereof may be easily adjoined together forming jumping pits of larger areas and different sizes.

The exemplary embodiments of the present invention are presented below in connection with the attached drawings on which:

Fig. 1 schematically illustrates an embodiment of a jumping pit according to the present invention in a perspective view and partial cross-section;

Fig. 2 shows another embodiment of a jumping pit according to the present invention in a vertical cross-section;

Fig. 3 shows a horizontal cross-section of a jumping pit shown in Fig. 2; and

Fig. 4 illustrates an operation of a jumping pit according to the present invention; and,

Fig. 5 schematically illustrates another embodiment of a jumping pit according to the present invention in a vertical cross-section. As shown in Fig. 1 , a jumping pit 1 according to the first embodiment of the present invention comprises an inflatable structure 2 covered with a deformable shield 3. The part of the pit 1 covered with the shield 3 is shown in an operational mode ready to use. The inflatable structure 2 comprises five substantially horizontal cylindrical pipes 21 and twenty eight vertical cylindrical poles 22, respectively parallel to each other. In this embodiment both pipes 21 and poles 22 have cylindrical shape of substantially the same cross-sectional diameter d that amounts about 230 mm.

Both pipes 21 and poles 22 are made of an air impermeable fabric such as composite, air impermeable fabric comprising a strong textile layer coated at one or at both sides by polymeric, in particular elastomeric, continuous films, or fabric reinforced with a plastic foil of high mechanical strength, in particular resistant to rupture and perforation, for example of polyester, polyamide or aramid fabric coated with a layer of polyurethane resin, epichlorohydrin, nitrile, natural rubber, butyl, polychloroprene, chlorosulfonated polyethylene, styrene/butadiene copolymer, or ethylene propylene diene monomer rubber or vinyl fabric. An exemplary fabric that may be used according to the present invention is a composite fabric P - 43 manufactured by LUBAWA SA, Poland (http://www.lubawa.com.pl).

Each pipe 21 and each pole 22 constitutes a separate, individually inflated element and to this end in this embodiment each pipe 21 and each pole 22 is provided with a check valve 23 for inflating thereof using a compressor or compressed air cylinder so that it will retain the internal pressure once inflated. Valves 23 also serve for discharging inflated air. Exemplary valves that may be used for this purpose are one way valves manufactured by Scoprega S.p.a. Italy (http://www.scoprega.it). In this embodiment, adjacent pipes 21 and poles 22 are connected by means of appropriate dismountable fasteners such as straps integrated with walls of the structure and the shield and braced with each other by means of cam buckles or dismountable Velcro fasteners (not shown in the figure), wherein each element is connected with others only after it has been inflated to form a complete inflated structure 2. The elements forming the structure 2 are connected in such a manner that bottom surfaces/edges of the pipes 21 and the poles 22 are substantially coplanar. The outermost pipes 21 may be provided with appropriate handles (not shown in the figure) facilitating carrying a structure, especially in inflated state.

The shield 3 has a layered construction and is made of polyurethane or latex foam sheet 31 covered with a layer of elastic coated fabric 32 of high resistance to rupture and mechanical perforation such as vinyl fabric. The shield 3 is connected to the structure 2 by means of appropriate dismountable fasteners such as straps integrated with walls of the structure and the shield and braced with each other by means of cam buckles or dismountable Velcro fasteners (not shown in the figure).

Figs. 2 and 3 show another embodiment of a pit 1a according to the present invention, forming an integral cuboidal segment. Segments 1a of this kind may be assembled next to each other in order to form a pit having larger dimensions. The shield 3 of the pit 1a is substantially the same as in the pit 1 of Fig. 1 but in this embodiment the inflatable structure 2a of the pit 1a has two additional pipes 21a disposed over the external pipes 21 that define substantially cuboidal shape of the structure 2a.

In this embodiment, the pipes 21 and poles 22 of the inflatable structure 2a are fluidly connected with each other by means of plastic flat connectors 24 glued to the walls of adjoining elements and provided with openings enabling for an unrestricted flow of air between these elements. Many appropriate connectors are known from the prior art therefore a construction of connectors 24 is not presented and described in details. Exemplary connector of this type is fastener produced by Scoprega S.p.a. Italy, and made in reinforced nylon that allows rapid mounting and dismounting, reducing the manpower necessary to assemble the inflatable structure according to the present invention. Such fasteners may be provided with one-way valves enabling for creating any arbitrary path of air through the inflatable structure. The inflatable structure 2a is provided with only one feeding check valve 23 and a safety pressure valve 25 to avoid overinflating the structure 2a above the predefined pressure value. The safety valve 25 serves also as a discharge valve.

While the structure 2a is being inflated, air flows through the feeding check valve 23 into the central pipe 21 and therefrom it is successively distributed through connectors 24 to the remaining elements 21 and 22 of the structure 2a as shown in fig. 2 by dashed line arrows. Similarly, while the structure 2a is being deflated, air flows out through connectors 24 and the opened discharge valve 25.

The height H of each pole 22 is larger than diameter d (or height) of the pipes 21 whereas the diameter d of pole 22 is the same as the diameter of pipes 21. In this embodiment the height H is slightly more than about two times larger than diameter d. The dimensions of the jumping pit 1a are as follows: the height H amounts 500 mm, the length L amounts 3000 mm, the width W amounts 2070 cm.

For a skilled technician it shall be obvious that in alternative embodiments the internal inflatable structure 2 according to the present invention may be divided into a set of separated subspaces in any facultative way. For example an inflatable structure may be formed from individual subunits comprising one pipe 21 and at least one or a number of poles 22 connected with this pipe via pneumatic connectors. Exemplary subunits of this kind might be the ones indicated in Fig. 1 by numerical reference 26, wherein adjacent subunits 26 would be connected with each other via Velcro or other type of releasable connectors.

Furthermore any facultative arrangement of pneumatic connectors may be used to inflate/deflate and/or stabilize a position of individual elements of the structure 2. To this end connectors may be furthermore provided with appropriate valving arrangements such as for example non-return (check) valves, providing sectioning of the internal space of a structure 2 into subspaces in such a manner that on one hand free air flow between subspaces is provided during inflating a structure and on the other hand an uncontrolled return-flow is blocked, so that in a case of puncture or loss of airtightness of one subspace the other subspaces would retain their pressure. Exemplary implementation of this idea in case of the embodiment 1a of Figs. 2 and 3 might involve providing pneumatic connectors 24 with non-return valves with a direction of flow oriented from the main inflation valve 23.

Though, cylindrical shapes of pipes and poles are preferred, for a skilled technician other shapes of the elements of the structure may also be contemplated such as for example prisms, cuboids or cones. According to the present invention the same height H of all poles is not required. For example in case of a complex jumping pit composed of a number of segments according to the present invention, such as the one shown in Figs. 2 and 3, heights of poles may be decreased in external segments of a pit.

An operation of a jumping pit according to the present invention shall be described with reference to Fig. 4 on which an oval element 4 symbolizes an object, e.g. a body of a jumper that has fallen in the area of a pole 22a of a pit, wherein dashed lines represent a jumping pit in an initial ready to use state. The pole 22a has been compressed by the jumper body 4 resulting in an outflow of an air therefrom mainly into the adjoining pipes 21 and to a lesser degree into the next elements of the pit inflatable structure. The pole 22a has also been buckled toward the centre point of a jumper fall. Furthermore, the shield 3 covering the inflatable structure increased an area of absorption of impact energy by providing that the fall impact resulted also in buckling neighbouring poles 22b and 22c toward the pole 22a. The energy of the fall has been dissipated mainly by deformation of the inflatable structure of the pit and also by flow of an air between particular pipes and poles of the pit surrounding impact area. These two mechanisms of fall energy absorption of the pits according to the present invention provide high efficiency in absorbing energy of fall of bodies having both vertical and horizontal velocity components.

Fig. 5 shows yet another embodiment of the pit 1c in which the top surfaces of the pipes 21 d and the poles 22d of the inflatable structure are coplanar so that a protective shield is not required.

The above embodiments of the present invention are merely exemplary. The figures are not necessarily to scale, and some features may be exaggerated or minimized. These and other factors however should not be considered as limiting the spirit of the invention, the intended scope of protection of which is indicated in appended claims.