Inflatable surfboard having a drive unit

Abstract

The invention relates to an inflatable surfboard with an inflatable hull component with two lateral arms (7a, 7b) which form a receptacle, and drive unit (6) which forms an outer contour which fits into the receptacle in a positively locking manner, and at least one fastening means (23, 23a, 23b, 24a, 24b, 26a, 26b, 27, 27a, 27b, 28, 61a, 61b) at the stern end of the surfboard (1), wherein the at least one fastening means (23, 23a, 23b, 24a, 24b, 26a, 26b, 27, 27a, 27b, 28, 61a, 61b) is inelastic.

Claims

1. An Inflatable surfboard comprising: an inflatable hull component (4) with two lateral arms (7a, 7b) which form a receptacle, wherein the inflatable hull component (4) has an upper surface defining a deck (13) of the inflatable surfboard; and a drive unit (6) which forms an outer contour which fits into the receptacle in a positively locking manner, and at least one fastening means (23, 23a, 23b, 24a, 24b, 26a, 26b, 27, 27a, 27b, 28, 61a, 61b) at a stern end of the surfboard (1), characterised in that the at least one fastening means (23, 23a, 23b, 24a, 24b, 26a, 26b, 27, 27a, 27b, 28, 61a, 61b) is inelastic and is designed as at least one belt (23, 23a, 23b, 24a, 24b, 26a, 26b, 27, 27a, 27b, 28) which is fastened to the two lateral arms (7a, 7b) and runs along the drive unit (6) at the stern end and is tensioned by means of a lever mechanism (24a, 26a, 24b, 26b) and the lever mechanism (24a, 26a, 24b, 26b) is configured as a toggle lever (30a, 30b) or a ratchet (31a, 31b) and in that the deck (13) has a single narrow U-shaped gap (22) with the hull component which forms a contact line between the drive unit (6) and the hull component (4).

2. Inflatable surfboard according to claim 1, characterised in that the at least one fastening means comprises two belt sections (23a, 23b, 27a, 27b) which in each case run from one of the two arms (7a, 7b) to the drive unit (6).

3. Inflatable surfboard according to claim 1, characterised in that the at least one fastening means (23, 23a, 23b, 24a, 24b, 26a, 26b, 27, 27a, 27b, 28, 61a, 61b) comprises two fastening means (23, 23a, 23b, 24a, 24b, 26a, 26b, 27, 27a, 27b) which are provided and in each case designed as a belt, which in each case runs from one side of the arms (7a, 7b) or runs from a stern end of the arms (7a, 7b) to the stern end of the drive unit (6) and releasably connects the stern end of the arms (7a, 7b) and the stern end of the drive unit (6) to one another.

4. Inflatable surfboard according to claim 1, characterised in that the at least one belt comprises a belt section (23, 23a, 24a, 26a, 27, 27a) and a corresponding belt section (23b, 24b, 26b, 27b), wherein the belt section is fastened by means of the ratchet or the toggle lever to a counterpart of the corresponding belt section (23b, 24b, 26b, 27b).

Description

(1) The invention is described with reference to five embodiments with 13 drawings. In the drawings:

(2) FIG. 1 shows a lateral sectional view of a surfboard according to the invention,

(3) FIG. 2a shows a rear view of a first embodiment of a fastening mechanism with two closed fastening belts at the stern end,

(4) FIG. 2b shows a rear view of the first embodiment with two open fastening belts at the stern end,

(5) FIG. 2c shows a rear view of the first embodiment with two open fastening belts at the stern end with the drive unit removed,

(6) FIG. 2d shows a rear view of a lever mechanism configured as a toggle lever.

(7) FIG. 2e shows a rear view of a lever mechanism configured as a ratchet.

(8) FIG. 2f shows a perspective view of the toggle.

(9) FIG. 3a shows a rear view of a second embodiment of a fastening mechanism with two closed fastening belts at the stern end,

(10) FIG. 3b shows a rear view of the second embodiment with two open fastening belts at the stern end,

(11) FIG. 3c shows a rear view of the second embodiment with two open fastening belts at the stern end with the drive unit removed,

(12) FIG. 3d shows a perspective view of the ratchet.

(13) FIG. 4a shows a rear view of a third embodiment of a fastening mechanism with a closed fastening belt at the stern end,

(14) FIG. 4b shows a rear view of the third embodiment of the open belt at the stern end,

(15) FIG. 4c shows a rear view of the third embodiment of the open belt at the stern end with the drive unit removed,

(16) FIG. 5a shows a rear view of a fourth embodiment of a fastening mechanism with a belt at the stern end,

(17) FIG. 5b shows a rear view of the fourth embodiment of a fastening mechanism with a belt at the stern end with the drive unit removed,

(18) FIG. 6 shows a rear view of a fifth embodiment of a fastening means at the stern end.

(19) FIG. 1 shows a surfboard 1 according to the invention. In principle, a surfboard is to be understood as a device on which the surfer 1 stands, kneels or sits and which floats on water and ideally has sufficient buoyancy to support the surfer. Where appropriate, the buoyancy can be chosen to be only so great that, together with the forward propulsion of a drive, it is sufficient to support the surfer.

(20) The surfboard 1 comprises a bow 2 and a stern 3. The surfboard 1 is designed substantially in two parts and comprises an inflatable hull component 4 which completely forms the bow region and central region of the surfboard, as well as a drive unit 6 in the stern portion of the surfboard 1 which is laterally flanked, maybe even at least partially enclosed, along its long sides by inflatable arms 7a, 7b of the hull component 4.

(21) The drive unit 6 comprises a jet drive 8. The jet drive 8 is only illustrated schematically here. The jet drive 8 comprises a water inlet 9 in an underwater surface 5 of the drive unit 6 and a water channel 11 with a water outlet 12 arranged on a rear end face 10 of the stern. The water outlet 12 is designed as a nozzle, which is not pivotable or is rotatable about an axis of rotation arranged vertically with respect to a deck 13. A rotor 14 is arranged in the water channel 11, and this rotor draws water into the water channel 11 and sprays it out of the nozzle contrary to a direction of travel, thereby providing propulsion for the surfer with the surfboard. A rotor 14 is understood here as a propeller and impeller.

(22) In a hull of the surfboard 1 a motor 16 for the rotor 14 is arranged in the drive unit, and drives the rotor 14 by means of a drive train 20, and also arranged there is a controller 21 for the motor 16, by which an output of the motor 16 can be controlled. Thus in particular the speed of the surfboard 1 can be controlled.

(23) The hull component 4 is preferably made from a drop stitch material. The drop stitch material is produced by the drop stitch method, wherein two or more synthetic fabric webs, preferably denier polyester fabric webs are laid one above the other. The two or more synthetic fabric webs are connected to one another by a plurality, i.e. thousands, of polyester threads. In this case the two fabric webs are kept spaced apart from one another, so that the space between the fabric webs which is filled with polyester threads can be filled with compressed air. The polyester threads are sewn to the two fabric webs on both sides, for example with the aid of a drop stitch sewing machine. The two fabric webs which are sewn to one another form the support structure which gives the hull component its mechanical strength in the inflated state.

(24) The two fabric webs which are connected to one another are cut to the required shape. The upper and lower fabric webs are preferably coated with PVC layers, preferably with three layers, and are pressed and glued layer by layer. The faces are glued, overlapping, to the seam strip and are pressed, so that the airtight hull component 4 is produced. The drop stitch method makes it possible to produce the inflatable hull component 4 with outstanding mechanical strength properties, which can withstand not only tensile loads but also compressive loads and shearing loads.

(25) The drop stitch outer skin of the inflatable hull component 4 is airtight and in the inflated state is exceptionally resistant to deformation, so that a surfer can stand and surf on the hull component 4 whilst retaining the external shape of the inflated hull component 4. The inflatable hull component 4 is filled with air under high pressure. The filling can take place by means of an air pump or a compressor. The compressor can be supplied for example with electrical energy by the battery 17 incorporated in the surfboard.

(26) The hull component 4 made from the drop stitch material is preferably low-noise, because the noise generated by the breaking of waves, but also by the drive, is damped by the hull. The hull component 4 is preferably subject to little vibration during operation, because vibrations are reduced by the drop stitch material. Since the hull component 4 is slightly deformable, impacts and waves etc. are advantageously absorbed. Furthermore, by comparison with conventional surfboards it is advantageous that the softer hull causes fewer injuries, for example if the surfboard 1 collides with the surfer in the event of the surfer falling off.

(27) The inflatable hull component 4 has a stern recess 20 which is illustrated for example in FIGS. 2a and 2c. The recess 20 is substantially U-shaped and has a lateral wall which is convex, i.e. curved into the recess 20.

(28) The drive unit 6 fits into the recess 20 in a positively locking manner. It has a concave wall which is correspondingly shaped towards the interior in a U shape and partially runs around the drive unit 6. The positively locking engagement of the convex wall in the concave wall prevents the drive unit 6 from sliding out upwards and downwards, i.e. in the direction of the deck 13 or in the direction of the underwater surface 5. In terms of height the drive unit 6 is dimensioned such that together with the surfboard 1 it advantageously forms a common deck 13. A deck 13 of the surfboard 1 is formed in one plane with a deck 13 of the drive unit 6. The entire deck 13 only has one narrow U-shaped gap 22 which forms the contact line between the drive unit 6 and the hull component 4.

(29) In cross-section perpendicular to a longitudinal direction L, the two lateral arms 7a, 7b of the inflatable hull component 4 are curved outwards approximately in a circular shape, at least along the entire periphery.

(30) In order to prevent the drive unit 6 from sliding out towards the stern end during the operation, various fastening means are provided. Although a force acts laterally on the drive unit 6 by the inflation of the hull component 4 and the two arms 7a, 7b, the force is not usually sufficient in order to produce sufficient friction to anchor the drive unit 6 in the hull component 4 even during operation.

(31) FIGS. 2a, 2b, 2c show a fastening means in the form of two belt sections 23a, 23b, which are in each case guided inwards from the exterior along the stern end surface 10 of the surfboard 1.

(32) Each of the two belt sections 23a, 23b is fastened at the side or at the stern end of a respective inflatable arm 7a, 7b. The fastening means may be a glued connection or a sewn connection or a combination of both or another connection. The belt sections 23a, 23b have ends 24a, 24b facing inwards to the recess. The ends 24a, 24b interact with lever closures 26a, 26b which are illustrated in a closed state in FIG. 2. The lever closures 26a, 26b are arranged spaced apart from both sides of the nozzle of the jet drive 8. The lever closures can be configured in particular as toggle lever closures or as ratchets.

(33) In FIGS. 2a, 3a, 4a the lever movements of the lever closures 26a, 26b, as well as the directions of movement of the ends 24a, 24b resulting from the movement of the lever closures 26a, 27a to and fro, are shown by double arrows or by arrows.

(34) FIG. 2b shows the lever closures 26a, 26b in an open state. In this state the lever closures are turned outwards in the direction of the arms 7a, 7b and free the ends 24a, 24b of the two belt sections 23a, 23b. During closure the ends 24a, 24b are inserted into the lever closures 26a, 26b, and by the action of force the lever closure is pivoted several times successively upwards and towards the nozzle and progressively tightens the respective belt section 23a, 23b.

(35) The belt sections 23a, 23b are not elastic. The elasticity necessary for closure is provided by the elasticity of the incompletely inflated arms 7a, 7b which, so long as they are not completely inflated, are configured to be significantly elastically variable in diameter.

(36) FIG. 2c illustrates the state in which the drive unit 6 is removed from the recess 20 of the inflatable hull component 4. The drive unit 6 can be exchanged or, for transport, can be kept separate from the then deflated hull component 4. FIG. 2d shows a back view of a lever mechanism configured as a pair of toggle levers (30a, 30b), wherein the toggle levers are located on a rear end of the drive unit (6) which allows a user to secure the two lateral arms (7a, 7b) against the drive unit (6) tightly. In addition, FIG. 2e shows a back view of another lever mechanism configured as a ratchet (31a, 31b), wherein the ratchet is located on a rea end of the drive unit (6). The ratchet can be tensioned to tightly secure the drive unit (6) to the two lateral arms (7a, 7b) of the surfboard (1). FIG. 2f illustrates the lever mechanism configured as the toggle lever 30b.

(37) In FIGS. 3a to 3c the closure according to the first embodiment is illustrated in a converse arrangement. The belt sections 23a, 23b are preferably permanently fastened, preferably adhered, sewn, riveted, screwed or otherwise fastened to the drive unit 6, they are arranged on both sides spaced apart from the nozzle in a horizontal plane with, again, in each case one of the ends 24a, 24b which in each case face outwards to the inflatable arms 7a, 7b. In each case a corresponding belt section 27a, 27b is fastened to the respective inflatable arms 7a, 7b by one of the lever closures 26a, 26b permanently fastened to the respective belt section.

(38) In FIG. 3a the two lever closures 26a, 26b are lowered and the belt sections 23a, 23b are gripped and thus secure the drive unit 6 in the recess 20 of the inflatable surfboard 1. In FIG. 3b the two lever closures 26a, 26b are opened, and the ends 24a, 24b of the two belts 23a, 23b hang down loosely from the stern end of the surfboard 1. Likewise the two lever closures 26a, 26b hang down loosely on the belt sections 23a, 23b.

(39) FIG. 3c shows the surfboard 1 in a dismantled state corresponding the second embodiment. FIG. 3d illustrates the lever mechanism configured as a ratchet having at least one fastening means 23b, 24b.

(40) FIGS. 4a to 4c show a third embodiment of the fastening means at the stern end. In this embodiment no part of the fastening means is arranged on the drive unit 6. Instead, a belt is gripped along the stern end surface of the surfboard 1. The belt consists of two belt sections 23, 27, and again an end 24 is formed at one end of one belt section 23 and the lever closure 26 is formed at one end of the corresponding belt section 27. The belt sections 23, 27 are fastened at the sides or on the stern end surface 10 of the two arms 7a, 7b, for example by a glued connection or a sewn connection. Turning of the lever closure 26 produces sufficient tension to pull the two inflatable arms 7a, 7b together, so that on the one hand a greater lateral force acts on the drive unit 6 and in addition the drive unit 6 can be prevented from sliding out at the stern end by the transversely extending belt. FIG. 4b illustrates the belt in an open state, and in FIG. 4c the drive unit 6 is removed from the hull component 4.

(41) FIGS. 5a and 5b show a fourth embodiment which constitutes a modification of the third embodiment shown in FIGS. 4a to 4b.

(42) In the fourth embodiment in FIGS. 5a and 5b a belt 28 is formed in one piece. It is guided from one arm to the other arm 7a, 7b along the stern end surface 10 thereof. There the two ends of the belt 23 are in turn firmly connected to the side or the stern end surface of the two arms 7a, 7b, that is to say sewn or glued or both or otherwise fastened. The surfboard 1 is constructed by first spreading out the deflated hull component 4 and optionally incompletely filling it with air, then the drive unit 6 is introduced into the recess 20 of the deflated or partially inflated hull component 4 and only then the belt 28 is laid along the stern end surface 10 of the drive unit 6. In this case, however, the belt 28 is not laid over the nozzle of the jet drive 8. Next the hull component 4 is inflated at high pressure. The length of the belt 28 is chosen to be so short that it is tensioned during inflation of the hull component 4 and an additional pressure can be generated laterally on the drive unit 6. In FIG. 5b the drive unit 6 is removed from the hull component 4.

(43) FIG. 6 shows a fifth embodiment, which is likewise the subject of this invention. In this case the stern fastening means is formed as a bend 61a, 61b in the lateral inflatable arms 7a, 7b. Each of the lateral inflatable arms 7a, 7b is hook-shaped or L-shaped and engages behind the drive unit 6 at the stern end, at least in some sections, by means of the bend 61a, 61b.

(44) In this case the nozzle remains free. A fastening means running completely along the entire stern end surface 10 is not provided. However, it has been shown that the bends 61a, 61b of the lateral arms 7a, 7b, with the hooks facing inwards to the surfboard 4, are sufficient when inflated at high pressure to prevent the drive unit 6 from sliding out at the stern end. In cross-section the drive unit 6 and the lateral arms 7a, 7b and also the embodiments according to FIG. 2 are designed in such a way that the arms 7a, 7b have a curvature directed towards the recess 20 and the drive unit 6 has an inwardly curved lateral wall, so that here too a substantially positively engaged connection is produced, which completely reliably prevents sliding out in the direction of the deck 13 or towards the underwater surface 5. In order to remove the drive unit 6 from the inflatable hull component 4, first of all at least some air must be released from the hull component 4.

LIST OF REFERENCE NUMERALS

(45) 1 surfboard 2 nose 3 tail 4 hull component 5 underwater surface 6 drive unit 7a arm 7b arm 8 jet drive 9 water inlet 10 end face at the stern end 11 water channel 12 water outlet 13 deck 14 rotor 16 motor 17 battery 20 recess 22 gap 23 belt 23a belt 23b belt 24a end 24b end 26a lever closure 26b lever closure 27 belt section 27a belt section 27b belt section 28 belt 61a bend 61b bend L longitudinal direction