Abstract:
The invention relates to a foldout stern-lowering means ( 1 ) which constitutes an integral part of the watercraft ( 38 ) and has at least three sectors (A, B, C) which can be walked on and optionally three further sectors (D, E, F) which can be walked on, with three different foldout modes: gangway, stairs and tender, with a safety means on the lifting means ( 18 ) in order always to return the stern-lowering means ( 1 ) into the starting position, and a safety means by means of an emergency lifting means ( 31 ) for people, and also to compensate for the additional weight of a stern-lowering means ( 1 ) by means of buoyancy means ( 39, 39 a) and to increase the comfort while underway and before anchoring, assisted by slosh plates ( 40 ).

Description:
TECHNICAL FIELD 
       [0001]    The invention relates to a foldout stern-lowering means for allowing people safe access to land and to water by means of steps, on the one hand, as well as for allowing a tender comfortable access to land and water by way of a ramp function according to the preamble of the first claim, on the other hand. 
       PRIOR ART 
       [0002]    Foldout lowering or otherwise adjustable staircases are known in the art, wherein technically optimally engineered staircases are found in the marine context, which are, moreover, usually extended by a motor, with the steps of the staircases being in most instances adjustable. The step adjustment therein is achieved by external push rods or chains. 
         [0003]    Lowerable platforms, especially for swimmers, divers and tender craft are known in the art, as disclosed in specifications DE196 02 331, U.S. Pat. No. 6,327,992 and U.S. Pat. No. 5,690,045. They allow for lowering persons or material comfortably into the water or take them onboard from the water. 
         [0004]    Also known are horizontal foldout stern components that serve as bathing platform or support for lifting and lowering tender boats. 
         [0005]    On yachts, even stairs that are extended from the belly of the watercraft or the swimming platform are known, as disclosed, for example, in specifications U.S. Pat. No. 6,789,648 B2, or components of the swimming platform that are lowered into the water in an arc and that have disposed thereon staircase elements, as disclosed in specification U.S. Pat. No. 7,121,226 B2, or means to lower tenders to water using the classic lowering means and additional tender supports with trailer, as disclosed in specification U.S. Pat. No. 7,293,521 B1. 
       DESCRIPTION OF THE INVENTION 
       [0006]    The object of the present invention seeks to provide a means on a watercraft that is simultaneously an integral component of the external contour of the watercraft while providing the user and a tender of the watercraft with safe and comfortable access to land and to water. 
         [0007]    Comfortable boarding and deboarding aids for persons and tenders are offered primarily for large yachts, where the weight and the complexity of handling such devices is an order of magnitude of subordinated importance, often being part of the lifting construction for tenders and/or garages. 
         [0008]    Due to the extra cost and weight, such comfort constructions are not available for smaller boats and yachts, because the stability of any such a construction may not be less therein than on large systems; plus, handling must be easier and safer by a multiple factor, as smaller yacht or boat owners must handle all tasks themselves and still keep an eye on safety, an aspect of even more critical importance in the leisure sector, since users here lack a handling routine. 
         [0009]    Furthermore, safe and comfortable access to and from the water is not only to be provided to people but also for tender boats and other technical equipment. At the same time, going on shore is to be rendered safe by utilizing the same means as a gangway. 
         [0010]    The invention takes advantage, on the one hand, of swimming platforms, which are in most instances already integrated in the boat design, as well as the highly placed back panels on the stern of yachts—increasingly also seen on medium sized boats—as part of the foldout stern-lowering means, which can be used on the inside—in the foldout state therefore constituting the visible side—as a gangway, when opened half-way, in that the inside of the swimming platform includes steps, the inside of the stern section is a walkway constituting, when being folded out further, a swimming platform with the highly place back panel of the stern becoming a staircase. Correspondingly, the foldout mechanism ensures that the staircase remains fixedly connected to the body of the boat, thus increasing the solidity of such a pivoting means. Any upward spraying of water on exteriorly positioned swinging arms is omitted; and in places without swinging arms, nothing can corrode and no weight is added, which is a further advantage of such a foldout version. The boat can also benefit, moreover, from an aesthetic point of view, because the construction can be incorporated in the overall design of such a watercraft. 
         [0011]    The foldout action is implemented by an electrical or hydraulic motor or operating cylinder, supported by one or a plurality of gas springs that also serve as emergency lifters. If there is an electrical failure in the onboard system, or a leak in the hydraulic lines, the folded out stern part can, nevertheless, still be raised and moved to the starting position, meaning as part of the back panel of the stern of a watercraft, using a breaking effect. 
         [0012]    The foldout operation includes three basic foldout modes, namely the gangway, stair and tender positions, with the latter acting as a ramp for lowering and retracting the tender or tender trailer, respectively. It is understood that any intermediate positions located there between can be reached and stopped at, a function that is particularly important for the gangway mode in order to be able to adjust the correct angle for going on land. 
         [0013]    If necessary, not only the stern hatch means must be folded back; in the event that a person goes overboard, time is of the essence and quick action is needed, either by means of the emergency switch that is installed below the swimming platform for folding out the stern lowering means, or by means of a pivotable staircase with holding bars attached thereto and a lock at the end of the lift, such that any person in the water is able to climb the stairs as well as lift his/herself out of the water by their own strength, thus simplifying coming back onboard considerably. The pivot process can be additionally supported by a spring. 
         [0014]    The additional weight in the stern of a watercraft may place a load on the trim of the craft. Buoyancy units are therefore fastened below the stern hatch means or the swimming platform, respectively, that correct the static trim, on the one hand, and improve the economy of the craft during travel, on the other hand, due to the hydrodynamics of the laterally attached buoyancy units that include, in addition, steps in the floor areas thereof; when anchored, the slosh plates, which can even connect the buoyancy units to each other, are able to thus reduce any rolling and pitching of the craft, when it is stationary while, nevertheless, not interfering with the current against the craft during travel. Moreover, the buoyancy bodies are height-adjustable and inflatable, thereby changing the volume conditions in the area of the stern of the watercraft, providing correspondingly the desired buoyancy. The additional weight of such stern-lowering means can be relayed to the stern of the watercraft such as, for example, by means of supports directly mounted on the lift motor housing. In addition, the swimming platform can be supported thereon, as well as the lateral buoyancy units. 
         [0015]    According to the invention, this is achieved by the characterizing features of the first claim. 
         [0016]    The core of the invention provides by means of a foldout stern-lowering means, which constitutes an integral part of the watercraft for embodying a simple and very comfortable staircase for persons or a ramp for a tender, and for said staircase having the capacity to be used, by way of additionally integrated stairs, as a gangway. Safety means on the mechanics and personal rescue devices improve the product quality, and the rigid or adjustable buoyancy units with slosh plates improve the comfort of the watercraft during anchoring as well as travel. 
         [0017]    Further advantageous embodiments of the invention can be derived from the dependent claims. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0018]    Embodiments of the invention will be illustrated in further detail based on the drawings below. Same elements in different figures are identified by identical reference signs. 
           [0019]    Shows are as follows: 
           [0020]      FIG. 1  shows a schematic, three-dimensional view of an offset stern-lowering means for a watercraft, with a back panel matched to the vehicle having a lifting element and a pivot bearing device fastened thereto; 
           [0021]      FIG. 2  shows a schematic, three-dimensional view of a folded out, offset stern-lowering means, with an integrated staircase having a staircase recessed therein as gangway means, with a foldout element having recessed steps therein and a foldout hand rail, as well as a rail element set; 
           [0022]      FIG. 3  shows a schematic, three-dimensional view of a folded out, offset stern-lowering means, with an integrated staircase having a staircase recessed therein as gangway means and a surface that can be walked on, as well as a foldable cover element and foldout hand rails; 
           [0023]      FIG. 4  shows a schematic side view of a lifting means that includes a lift motor with block on a connecting wheel, and a further connecting wheel with mounted gas spring, as well as a shaft which, by means of spring damping, can be connected to a lever element on which is mounted the offset stern-lowering means, and a connecting screw that that compresses the two connecting wheels against a spring, which can be released manually or by remote control; 
           [0024]      FIG. 5  shows a schematic side view of a emergency lifting means that is mounted on the swimming platform and that includes an emergency lift motor plus a spring with an auxiliary transmission for the manual lever and as a lock; 
           [0025]      FIG. 6  shows a schematic view of the stern of a watercraft with supports as well as rigid and adjustable buoyancy units and slosh plates. 
       
    
    
       [0026]    Only elements that are essential for an immediate understanding of the invention are presently shown. 
       WAYS TO EMBODY THE INVENTION 
       [0027]      FIG. 1  shows a schematic, three-dimensional view of an offset stern hatch means  1  for a watercraft having a back panel  2  matching the craft, a standing area  3 , and laterally mounted thereto lever element  4  and a pivot bearing device  5 . The stern hatch means  1  is an integral component of a stern on a watercraft that can be unfolded using a motor or manually, and that has the known quality surface on the standing area  3  such as, for example, a teak flooring or a plastic anti-slip liner, and the like. If possible, the stern hatch means  1  should be a light-weight component with the hollow spaces filled by a closed cell foam material. The pivot bearing device can be continuous in order to reinforce the entire construct; similarly, the lever element  4  can be a continuous frame around the stern hatch means  1  that helps to reinforce the component. The stern hatch means  1  has a form and utility that is equal to a swimming platform, due to the standing area  3 . 
         [0028]      FIG. 2  shows a schematic, three-dimensional view of a folded out, offset stern-lowering means  1  having an integrated staircase  6  with water run-off  6   a  and a recessed gangway staircase  7  as gangway means, with a foldout element  8  having recessed steps  9  therein and a foldout hand rail  10 , as well as runner element set  11  at the head standing area  12 . Folding out the stern hatch means  1  by 180°, if possible using a motor, the staying area in the stern of the watercraft is virtually doubled, on the one hand, due to the gangway staircase  7  that is covered up in this position by the foldout element  8 , which is provided with hinges  13 , and, on the other hand, by the head standing area  12 . Access to and from the water is provided via the generous staircase  6  that can be almost as wide as the width of the watercraft. Due to this generous staircase configuration, it is advantageous to be able to utilize a hand rail  10  that can be unfolded laterally and locked into place on the staircase  6  (not shown here); or with the same applying to a gangway staircase  7  as well. The foldout element  8 , which includes cutouts that can be used as steps, can be extended in the telescopic or foldable version beyond the end of the staircase  6 , thus allowing tall swimmers even more convenient access to the staircase  6 . 
         [0029]    If the stern hatch means  1  is unfolded, for example, only by 135°, this constitutes an access way by means of the gangway staircase  7  upon which it is now possible to utilize the foldout element  8  that is folded on the side of the staircase  6  and that can be used as horizontal gangway. In the telescopic version, the foldout element  8  can be a path which can be walked on beyond the stern hatch means  1 . The foldout element  8  can be raised via a wedge means, such that it is possible to gain easy land access even to higher terrain. 
         [0030]    The stern hatch means  1  can also be unfolded over 180° in order to let a tender to water or pull the same up again. This occurs by means of a runner craft that is advantageously routed inside the runners  11 . A runner craft of this kind thus always stays in the tack with the tender thereof, and it is possible to correspondingly trigger the same electronically, and it is unable to become detached from the track. 
         [0031]    Upon immersing the stern hatch means  1  complete with the integrated staircase  6  thereof in the water, it is extremely advantageous for well-placed water run-offs  6   a  to be present; otherwise the stern hatch means  1  with the staircase  6  thereof acts as an excavator bucket whereby much water is lifted, weighing heavily, and pouring over the stern of the watercraft when the stern hatch means  1  is folded together. Such water run-offs  6   a  can, on the one hand, be mounted directly on the side of the staircase  6  and, additionally, be hidden inside the stern hatch means  1  as elegant water run-off tubes, such that they direct the water away in a manner that is barely visible or audible, for example near the water line in the stern of the watercraft. 
         [0032]    Correspondingly, the stern hatch means  1  is multifunctional in the different positions—in the closed state, by way of standing area  3 , it has sector A which can be walked on; in the opened state, by way of head standing area  12 , it has sector B which can be walked on; by way of staircase  6 , it has sector C which can be walked on; by way of gangway staircase  7 , it has sector D which can be walked on; and by way of extendable foldout element  8 , it has a further walkable area. 
         [0033]      FIG. 3  shows a schematic, three-dimensional view of an unfolded, offset stern-lowering means  1  with integrated staircase  6 , with recessed gangway staircase  7  as gangway means, with a hatch element  14  having a spring  15  and a walking area  16  that has an extendable extension  17 , and a second, parallel foldout hand rail  10 , as well as runner element set  11  on the head standing area  12 . The function is identical as in  FIG. 3 , with the exception that the staircase  6  is not configured as being quite as wide in this case; instead, a part thereof is reserved for the walking area  16 , sector E which can be walked on and can simultaneously include an integrated extendable extension  17 , and which is walkable sector F. The walking area  16  and the extendable extension  17  can include high-value surface materials matching the craft, and the extendable extension  17  can also include steps  9 . The walking area  16  can also be varied in terms of the incline thereof relative to staircase  6  similarly to the stern hatch means  1 , such that a very precise adjustment of the desired height can be achieved for going on land. When the stern hatch means  1  is closed, it is possible for the hatch  14  to be connected to the craft or the swimming platform there below using a hook-and-loop means, or magnets or a ratchet-and-pawl mechanism, or a locking element that can be electrically actuated, or the like. When the stern hatch means  1  is folded up, for example, by 135°, the hatch element  14  adheres to the ground below and does not fold up as well, whereby the stern hatch means  1  automatically includes a gangway staircase  7  leading to walking area  16 . If the stern hatch means  1  is folded out further to 180°, the foldout angle is too great for the folding element  14 , it detaches from the ground below, and it is pulled shut by means of spring  15 , for example a gas tension spring, whereby the gangway staircase  7  is automatically covered, such that an even larger surface is achieved for the head standing area  12 , walkable sector B. 
         [0034]      FIG. 4  shows a schematic side view of a lifting means  18  that holds the stern hatch means  1  via the lifting element  4 , and a shaft  19  is mounted on the lifting element  4  with a rubber bearing  28  disposed there between, and the shaft  19  is connected to a connecting wheel  20 . By means of a slotted toothing  21 , or the like, the connecting wheel  20  is connected to a further connecting wheel  20   a  that also includes a slotted toothing  21 , whereby the connecting wheels  20 ,  20   a  are fixedly connected to each other by means of a compression spring  22  and mounting screw  23  disposed there between. A load band  24  is fastened to the connecting wheel  20  that engages with a gas spring  25  and on connecting wheel  20   a,  additionally having a block  26 , there is mounted a further load band  24 , which engages on the lift motor  27 . The two connecting wheels  20  and  20   a  can be separated from each other by means of a manual tool  29  or a remote control  30 . 
         [0035]    The lifting means  18  is a central factor in the implementation of a safe operation of the stern hatch means  1 , as, even in a light-weight construction, the large-surface stern hatch means on a yacht can still be a heavy part. The torques for the hatch movements can thus be considerable; the safety of such a movable part must take high priority, as well as security of function, even in the event of a failure of the electrical supply on the lift motor  27 , such that the stern hatch means  1  can be safely folded shut at any time and without great force expenditure. 
         [0036]    Therefore, the lifting means  18  is made of two drive mechanisms, namely the gas spring  25 , which is responsible for providing a correspondingly lifting power, and the lift motor  27 , which must also provide a corresponding lifting power, such that the gas spring  25  and lift motor  27  acting in conjunction virtually provide a double lifting power; meaning, respectively, the lift motor  27  and the associated transmission must only have half the force in order to generate a corresponding torque. A second corresponding control of the gas spring  25 , which is presently not shown, is tasked to act as a brake during the folding operation over the vertex point; similarly, the lift motor  27  is also able to execute a braking function. The lift motor  27  can be actuated hydraulically or electrically; it can be self-decelerating or be held in a desired position by means of an additionally installed block  26 , even in high waves or with corresponding loads acting on the stern hatch means  1  in the gangway position. The block  26  includes a lifter  26   a  and a toothed disk  26   b . If the lift motor  27  and the electrical block  26  fail, locking can be circumvented in order to detach the connecting wheel  20   a  from the connecting wheel  20 , which was locked unintentionally, in that the mounting screw  23  is loosened whereby the compression spring  22  axially presses the connecting wheel  20   a  to the outside, as indicated by arrow D, possibly together with lock  26 , such that the two connecting wheels  20 , 20   a  ultimately no longer touch, and the connecting wheel  20  can rotate freely, meaning powered by gas spring  25 . The connecting wheel  20  is connected to shaft  19  and gas spring  25 ; the stern hatch means  1  thus raises itself over the vertex point of the hatch motion and is decelerated by the same gas spring  25  or a second gas spring  25  or an oil damping or another braking means, and the stern hatch means  1  can thus be gently folded back into the original position thereof. The mounting screw  23  is loosened either manually using a hand tool  29  such as, for example, an Allen wrench or via a remote control  30  that is can be activated by means of a cordless screwdriver. The rubber bearing  28  between shaft  19  and lifting element  4  serves for cushioning should the stern hatch means  1  come in contact with the landing planks, when it is in the gangway position, thus absorbing the impact energy. Instead of a rubber bearing  28 , another means for limiting torque are conceivable as well. 
         [0037]      FIG. 5  shows a schematic side view of an emergency lifting means  31  that is mounted on the swimming platform  32  and includes an emergency lift motor  27   a  with auxiliary transmission  33 , thus actuating the step ladder  34  and, simultaneously, the hand rail  35  by a lock  36  mounted thereto. In order to not rely on the emergency lift motor  27   a,  the lever  37  is mounted on the emergency lifting means  31  in order swing out the step ladder  34  manually. For eventualities, an emergency switch  38  is provided under the swimming platform  32 , such that a person can operate the stern hatch means  1  from the water to bring the same in the foldout mode. 
         [0038]    Emergency ladders are obligatory for watercraft of certain sizes; if a person goes overboard, it is thus possible for such a person to come back on board using such an emergency ladder. It is often difficult to open such emergency means, and often there are no holding possibilities provided on the swimming platform  32  for a person to climb out of the water and come back onboard by his or her own power. Folding out the stern hatch means  1  can also take too long when a person in the water is frantically searching for rescue, although a water-proof emergency switch  38  is located below or on the swimming platform  32  by which the person who went overboard is able to activate the stern hatch means  1 , thereby unfolding the same. 
         [0039]    The emergency lifting means  31  mounted below the swimming platform  32  includes a swing-out step ladder  34 , powered by the emergency lift motor  27   a , provided with an auxiliary transmission  33 , that swings out, by a gear ratio step up, the hand rail  35  simultaneously with the former in the same direction, such that when the step ladder  34  has reached the desired position thereof, the hand rail  35  has also reached the desired position thereof. The lock  36  ensures that the hand rail  35  remains in the desired position, even when a person pulls on it while climbing up the same. This makes the climbing process much easier and thus also safer. The actuation of the switch—presently not shown—occurs in that the person in the water pulls on the step ladder, thus triggering the contact; and/or an auxiliary emergency switch is mounted on the stern of the watercraft and activated by a third party. If the emergency lift motor  27   a  also fails during the emergency, a lever  37  is attached to the same that has the same function as represented in  FIG. 4  regarding the mounting screw  23 , such that the step ladder  34  is detached from the emergency lift motor  27  and able to swing freely downward. The auxiliary transmission  33 , however, remains functional, meaning the hand rail  35  is also extended. Instead of as described in  FIG. 4 , the emergency lifting means  31  is not retracted but, upon release by the lever  37 , the step ladder  34  is automatically extended completely using the gas spring  25  or spiral spring, and the like, such that the emergency lifting means  31  is swung out and the step ladder  34  and hand rail  35  are automatically locked at the point of the stop, specifically without the person in the water having to do anything. 
         [0040]      FIG. 6  shows a schematic view of the stern of a watercraft  38  with a closed stern hatch means  1 , the lifting means  18 , the supports  42 , as well as the buoyancy units  39  and a height-adjustable buoyancy unit  39   a  as well as slosh plates  40 . Additional weights on the stern  38   a  of a watercraft  38  can cause trimming of the craft, meaning, respectively, the craft is permanently weighed heavier in the stern, lying unevenly in the water. The use of buoyancy units  39  in connection with the stern hatch means  1  makes sense because the buoyancy units  39  do more than compensate for extra weight in that they provide useful services in terms of hydrodynamics as well; especially with a stepwise floor, now shown here, they improve the driving properties of a watercraft  38  considerably. Moreover, they have a stabilizing effect, when the watercraft  38  is anchored. With a foldout stern hatch means  1  of this kind, the lever arm changes unfavorably to the rear during the folding-out operation. To compensate for this situation, optimum buoyancy is helpful, which only becomes active when the stern hatch means  1  is immersed in the water, as well as the light-weight construction of the stern hatch means  1  and an extendable or inflatable buoyancy unit  39   a,  which is located, for example, in the middle part on the stern  38   a  and enlarges the buoyancy volume in the water parallel to the amount that the watercraft  38  becomes weighted to the stern area due to the unfolding of the stern hatch means  1 . This can be monitored and corrected by means of position sensors and a controller, or a fixed algorithm that detects the foldout angle and provides in this regard each time a predetermined buoyancy volume in that the lowerable buoyancy unit  39   a  that is in as much as possible above the waterline in the resting state is now immersed below into the water, whereby additional volume is generated translating to buoyancy in the area of the stern  38   a,  whereby the shifted weight of the stern hatch means  1  is counteracted; or the buoyancy unit  39   a  is inflatable and a corresponding air volume is introduced in order to achieve additional buoyancy volume in this manner. During travel, the buoyancy body  39   a  is refolded or retracted. Lowering and retracting occurs vertically or in the shape of an arc using an operating cylinder  42 , or it is subject to a forcible control by means of a presently not shown linkage that is connected to the stern hatch means  1 . Furthermore, it is advantageous for the swimming platform  32  to be reinforced by mounting support elements  43  that act simultaneously with the lifting means  18 , such that, ultimately, the load acting in the area of the stern hatch means  1  can be additionally further distributed via the support elements  42  over the stern  38   a.  The support elements  42  therein can also include additional expedient supports on the inside of the watercraft  42 . 
         [0041]    Slosh plates  40  are mounted in the stern  38   a  or/and on the buoyancy units  39 ,  39   a  to improve any rolling but also pitching of the watercraft  38  still further; said slosh plates are configured as large-sized as possible and do not interfere with the current against the body of a watercraft  38 ; and the slosh plates  40  can be, due to the buoyancy units  39  located on both sides, stretched continuously from one side of a watercraft  38  to the other, whereby they are also correspondingly easy to install. The otherwise horizontally disposed slosh plates  40 , mounted over or next to the buoyancy units  39 , can be easily bent downwards in the travelling direction as well, such that the sea water following behind does not press the stern  38   a  of the watercraft  38  downward by the pressure thereof. Also, the slosh plates themselves  40  are able to generate static or/and dynamic buoyancy, and they can be manufactured of metal or plastic. 
         [0042]    It is understood that the scope of the invention is not limited to the shown and described embodiments. 
       LIST OF REFERENCE SIGNS 
       [0000]    
       
           1  Stern hatch means 
           2  Back panel 
           3  Standing area, sector A which can be walked on 
           4  Lifting element 
           5  Pivot bearing device 
           6  Staircase, sector C which can be walked on 
           6   a  Water run-off 
           7  Gangway staircase, sector D which can be walked on 
           8  Foldout element 
           9  Step 
           10  Hand rail 
           11  Runner element set 
           12  Head standing area, sector B which can be walked on 
           13  Hinge 
           14  Hatch element 
           15  Spring 
           16  Walking area, sector E which can be walked on 
           17  Extension, sector F which can be walked on 
           18  Lifting means 
           19  Shaft 
           20 ,  20   a  Connecting wheel 
           21  Slotted toothing 
           22  Compression spring 
           23  Mounting screw 
           24  Load band 
           25  Gas spring 
           26  Block 
           26   a  Lifter 
           26   b  Toothed disc 
           27 , Lift motor 
           27   a  Emergency lift motor 
           28  Rubber bearing 
           29  Hand tool 
           30  Remote control 
           31  Emergency lifting means 
           32  Swimming platform 
           33  Auxiliary transmission 
           34  Step ladder 
           35  Hand rail 
           36  Lock 
           37  Lever 
           38  Watercraft 
           38   a  Stern 
           39  Buoyancy unit 
           39   a  Adjustable buoyancy unit 
           40  Slosh plate 
           41  Emergency switch 
           42  Operating cylinder 
           43  Support elements 
         D Spring pressure direction