Abstract:
Offshore wind power installations usually require a landing stage or landing pier so that craft, in particular ships, can guarantee supply and transportation services. In the case of small offshore installations, these are usually simple jetties with possible ways of making boats fast. In the case of larger offshore installations at which larger supply ships land, the landing installations are of a more expensive and complicated structure and have for example supply intermediate storage facilities such as fuel tanks and loading equipment such as cranes.

Description:
TECHNICAL FIELD 
     The present invention concerns a landing stage, in particular for offshore wind power installations. 
     BACKGROUND OF THE INVENTION 
     Offshore wind power installations usually require a landing stage or landing pier so that craft, in particular ships, can guarantee supply and transportation services. In the case of small offshore installations, these are usually simple jetties with possible ways of making boats fast. In the case of larger offshore installations at which larger supply ships land, the landing installations are of a more expensive and complicated structure and have for example supply intermediate storage facilities such as fuel tanks and loading equipment such as cranes. 
     Helicopters, because of their lower service load capacity, are usually employed for the rapid transportation of personnel. 
     If, because of high wind speeds and a heavy sea, it is difficult for ships to land, to the point of being impossible, then helicopters temporarily represent the only supply and transportation option. Many offshore installations which do not have any landing area for helicopters, under such weather conditions, can then be supplied with a helicopter only in such a way that the helicopter which has flown to the installation remains in the air and supply or inspection is effected for example by means of a cable winch on the helicopter. Maneuvers of that kind are difficult and dangerous. 
     Offshore wind parks comprising a plurality of individual wind power installations which are disposed in the sea but also other, for example small, individual offshore installations, by virtue of their construction, afford scarcely any possible way of providing a landing area for helicopters on them. In addition, in the case of wind power installations, the danger to the helicopter as it flies towards the installation, due to the rotating rotor blades of the wind power installation, represents an addition serious problem. 
     The separate arrangement of the mooring location or berth for ships on the foundation legs and of the landing area for the helicopter at a higher position on the drilling rig, as is known from offshore drilling rigs, is essentially out of the question, because of the rotor being arranged at that location in the case of wind power installations, and, under the constricted situation in terms of space on offshore installations, because of separately required logistics and the respective space required for same, results in a disadvantageous waste of building space. 
     SUMMARY OF THE INVENTION 
     The object of the present invention is to provide a landing stage for ships and for helicopters, which while being of a simple structure can be used on offshore and shore installations. 
     That object is attained by a landing stage having the features set forth in claim  1 . Advantageous configurations of the invention are set out in the appendant claims. 
     In accordance with the invention a landing stage has a mooring location or berth for ships and a landing area for helicopters. The landing stage is disposed in particular on offshore wind power installations, but also on installations which are erected on a bank or shore. In accordance with the invention in that case there is a common route link from the mooring location and the landing area to the installation. In that way, in accordance with the invention, logistical devices can be set up in such a way that they can be used jointly for the mooring location and the landing area. These are for example buildings in which landed people can (initially) seek protection, materials which have been landed or which are ready for collection can be held in intermediate store, but also fuel stores which are arranged together as well as navigational aids which can include signal navigation lights, radio direction-finding transmitters, but also pilot rooms with radar surveillance. Because in particular offshore installations of any kind are substantially basically highly restricted in terms of their space aspects, a concentration in accordance with the invention of logistically relevant locations (transport interface for ships and helicopters from the installation to the outside world) is extremely advantageous. The common landing stage, preferably with the jointly usable logistical devices, advantageously concentrates in accordance with the invention transport from the landing stage by way of the common route link to the installation where then further distribution from the common route link can be effected in any desired manner in a logistically simply plannable fashion. 
     The landing stage according to the invention is preferably mounted to an offshore wind power installation whose generator is driven by a rotor which rotates at the tip (pod) of a pylon about a horizontal axis. In that case the landing area for helicopters, in order to guarantee safe take-offs and landings, is remote from the pylon preferably by at least a third of the length of a rotor blade. 
     Preferably the landing stage according to the invention has independent foundations in the sea, that is to say the mooring location and the landing area are supported on a foundation on the seabed or supported floatingly on the surface of the water, more specifically individually or separately from each other and in then any combination of the kind of support. 
     Preferably the landing stage is disposed laterally of the installation at the prevailing lee side of the installation. In that way the landing stage is advantageously disposed in the region of the installation which is sheltered from the wind, so that both wind and also sea swell break against the installation and only act with an alleviated force on the landing stage. 
     In accordance with the invention, that effect is further enhanced if the landing stage is preferably mounted rotatably about the offshore installation and is thus always oriented into the lee side of the installation by the afflux flow of wind. Particularly suitable for this embodiment of the invention is the floating foundation for the landing stage, which for example can be in the form of a pontoon of large area, which can be connected by way of a bridge for example to the base region of an offshore wind power installation and then is supported there for example by means of a ring sleeve or a rotor member on the periphery of the base. When applied to wind power installations, that design configuration has an additional substantial advantage: the greatly projecting rotating rotor blades of the generator propeller represent a major danger to a helicopter flying towards the installation. If now however in accordance with the invention the landing stage is oriented by the wind into the lee side of the wind power installation, the air space above the landing stage is at any event outside the rotational range of the generator propeller for the latter is in accordance with its function oriented transversely with respect to the lee side against the wind—in other words: in relation to the wind direction, the plane of rotary movement of the generator propeller is then perpendicularly markedly upstream of the air space above the landing stage and does not cut through the air space. Furthermore, the helicopter can advantageously come in to land on the landing area against the wind without being impeded by the installation. 
     The embodiment of the landing stage according to the invention with the floating foundation also has the advantage that in respect of its height it follows the movement of the tides, which is of substantial advantage for the mooring location of the ships. 
     The landing stage according to the invention is preferably a structure made up of any combination of steel framework, plates, concrete and/or wood with suitable corrosion protection in relation to sea water and other environmental influences. 
    
    
     BRIEF DESCRIPTION OF THE FIGURES 
     Preferred embodiments of the invention are described hereinafter with reference to the accompanying drawings in which: 
     FIG. 1 shows a side view of a first embodiment of the present invention, and 
     FIG. 2 shows a side view of a second embodiment of the present invention. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     In the two Figures, identical components or components which correspond to each other in any way are denoted by the same references. With reference to FIGS. 1 and 2, shown therein is an offshore wind power installation  2  with a rotor  4  with a substantially horizontal axis of rotation. The rotor  4  is connected or coupled to a generator (not shown) in a pod  6 . The pod  6  (or the illustrated machine housing) can be oriented about a vertical axis  8  with respect to the current wind direction  9  by a transmission arrangement (not shown) which is also arranged in the pod. 
     The pod  6  with the rotor  4  is mounted on the tip of a pylon  10  rotatably about the axis  8 . 
     The pylon  10  of the wind power installation  2  is fixedly erected in the sea  12  as shown in FIG. 1 by means of a foundation  14   a  of concrete and as shown in FIG. 2 by means of lateral struts  14   b  on the seabed  16 . 
     The wind power installations  2  shown in both FIG.  1  and also FIG. 2 each have a landing stage  20   a ,  20   b . The landing stage  20   a  shown in FIG. 2 is in the form of a steel framework structure with a concrete platform  22  and is secured fixedly to the pylon  10  of the wind power installation  2  laterally of the installation  2  and is fixedly supported by way of a steel lattice pillar  24  itself in the sea  12  on the seabed  16 . 
     The horizontal concrete platform  22  at the top side forms a landing area  25  for a helicopter  26 . In particular at the edge  28  of the platform  22 , which is most remote from the pylon  10 , the platform  22  together with the pillar  24  which projects perpendicularly downwardly from that edge  28  to the seabed  16  forms a mooring location or berth in the form of a pier for ships  30 . 
     Both the landing area  25  for helicopters  26  and also the mooring location  28  for ships  30  are connected by way of the platform  22  which is fixed to the pylon  10  by a common route link  32  between on the one hand the landing area and the mooring location  28  and on the other hand the pylon  10  of the wind power installation  2 . Thus, personnel and equipment which are transloaded by means of the helicopter  26  or the ship  30  on the landing stage  20 , by way of the common route link  32 , follow a common path through a door  34  into the pylon  10  where for example by means of an elevator (not shown) they can be conveyed in the pylon  10  to the pod  6  at the tip thereof, if for example repair or maintenance operations have to be carried out there. 
     The landing stage  20   a , in relation to a prevailing wind direction at the location of the wind power installation  2 , is disposed at the lee side thereof and is securely fixed there, as described. In that way, the force of wind and sea swell both against the landing area  25  and also against the mooring location  28  is broken by the pylon when wind is blowing from the prevailing direction. 
     Safe take-offs and landings of helicopters  26  on the landing area  25  are guaranteed by a sufficiently large vertical distance between the landing area  25  and the diameter described by the tips of the rotor blades  4 . 
     Referring now to FIG. 1 the wind power installation  2  has a landing stage  20   b  which differs from the landing stage  20   a  in FIG. 2 by the features described hereinafter. 
     The landing stage  20   b  shown in FIG. 1 is a steel plate/steel framework structure whose concrete platform  22  is supported on a pontoon  36 . Disposed in the interior of the pontoon  36  are storage spaces (not shown). The platform  22  whose top side, as already described with reference to FIG. 2, forms the landing area  25  for helicopters  26  and whose lateral edges form the mooring location  28  for ships  30 , is therefore not fixedly anchored in the sea on the seabed  16  but floats on the surface of the sea  12 . As a result, there is always an identical vertical spacing between the platform  22  and the surface of the sea  12 , which is of substantial advantage in particular for loading and unloading ships  30 . 
     The platform  22  with the landing area  25  and the mooring location  28  on the floating platform  36  is connected to the pylon  10  of the wind power installation  2  by way of a bridge  32 . The bridge  32  thus forms the common route link from the landing area  25  and the mooring location  28  to the pylon  10  of the wind power installation  2 . The bridge  32  is supported both on the pontoon  36  and also the pylon  10  firstly pivotably about a respective horizontal axis. Those mounting locations  38  ensure that the floating pontoon  36  is freely enabled to perform vertical movement by virtue of the movement of tides in the sea  12 . 
     The landing stage  20   b  shown in FIG. 1 is also connected by way of the bridge  32  rotatably about the vertical axis  8  of the pylon  10  of the wind power installation  2 . In that way the landing stage  20   b , connected to the pylon  10  by way of the bridge  32 , can float freely at a given spacing around the pylon  10 . In that situation it is oriented by the wind direction  9  at the time. That provides firstly that the landing stage  20   b  is always at the lee side of the wind power installation  2  that is to say not only with the prevailing wind direction but with any current wind direction—and is thus always protected by the pylon  10  from the influences of wind and swell. So that the pontoon  36  can float as smoothly as possible on the sea, structural measures are known, for example the pontoon  36  should be as heavy and as of large surface area as possible. A second advantage of the landing stage  20   b  being oriented by the wind  10  to assume a position in the lee of the wind power installation  2  concerns flight safety when helicopters  26  are taking off from and landing on the landing stage  20   b : by virtue of the fact that the propeller  4  of the wind power installation  2  is always oriented in the wind direction  9 , the airspace above the landing stage  20   b , as shown in FIG. 1, which is oriented towards the lee side, does not in any case have the rotor blades  4  of the wind power installation  2  passing therethrough. The helicopter  26  can thus take off and land vertically without hindrance and can fly to the landing stage  20   b  against the wind without being impeded by the wind power installation  2 . 
     The described rotatable support for the landing stage  20   b  about the pylon  10  is afforded by an annular ‘balcony’  40  which is rotatable in the form of a sleeve about a region at the lower end of the pylon  10 . The balcony  40  is fixed on the pylon  10  in the vertical direction so that the door  34  in the pylon  10  is at any event always accessible from the balcony  40 . 
     It is possible to see on the landing stage  20   b  buildings  42  which can be used jointly from the landing area  25  and the mooring location  28  and navigational aids  44 . 
     From the foregoing it will be appreciated that, although specific embodiments of the invention have been described herein for purposes of illustration, various modifications may be made without deviating from the spirit and scope of the invention. Accordingly, the invention is not limited except as by the appended claims.