A METHOD AND APPARATUS FOR RAISING A LOAD ONTO A TOWER

Abstract: Apparatus for raising a generator (2) onto a top platform (4) of a tower (5) comprises a jib (10) having jib members (20, 21) which are separably secured together. The jib (10) is raised by a hoist towards the top of the tower (5), and a piston rod (12) of a ram (14) pivotally engages a bore (16) in the tower (5) so that the jib (10) is pivotal from a first orientation with the jib (10) horizontal to a second orientation with the jib (10) extending vertically upwardly. A pair of winch ropes (55) around pulleys (56, 57) on the jib (10) are attached to the generator (2) for raising the generator (2) to the jib (10) when the jib (10) is in the horizontal first orientation. The jib (10) is then pivoted in the direction of the arrow A into the second orientation by secondary winch ropes (65) and the generator (2) is then lowered onto the platform (4) where it is secured thereto. On securing of the generator (2) to the platform (4) the jib (10) is disengaged from the tower (5) and lowers to the ground.

Description: "A method and apparatus for raising a load onto a tower" The present invention relates to a method and apparatus for raising a load onto a tower, and in particular, though not limited to a method and apparatus for raising a wind-powered generator with its propeller attached from the ground onto a top platform of the tower. Such wind-powered generators, in general, comprise a relatively tall tower structure, typically, of 30M to 70M in height, and in many cases even higher. The tower structures, in general, are of circular or other cross-section, and are formed in situ of reinforced concrete, or may be of steel of a lattice type construction, and in which case, would be assembled on site. On construction of the tower structure, the wind-powered generator is raised from the ground onto a top platform of the tower, and subsequently the propeller is secured to the generator. Such generators, in general, are referred to as nacelles, and are relatively large structures comprising a housing in which the generator is housed, as well as a gearbox, a yawing system and other control equipment and apparatus, such as control gear and the like. Such nacelles can weigh up to 40,000Kgs or more. Thus, in order to raise the nacelle from the ground onto the tower platform relatively heavy-duty and tall cranes are required, typically, a tower crane. In general, this requires transporting a tower crane onto the site. In general, wind powered generators are located in remote locations, generally, in wind farms where a plurality of wind powered generators are located. In general, there are two main reasons as to why wind farms are to be found in remote locations. Firstly, it is desirable that wind farms be located away from centres of population, since the generators tend to create quite a high noise level. The second reason, and in general, the more important reason as to why wind farms are to be found in remote locations is that in general, wind conditions for wind farms tend to be optimum in such locations, for example, high up on mountains, in coastal areas which are exposed to relatively strong prevailing winds and the like. Access to such remote locations, in general, is restricted, in that roads may be narrow and of poor quality, and in certain cases, may be non-existent. Where such wind farms are located on a mountain or in open bogland or a moor, the land, in general, is unsuitable for supporting heavy wheeled vehicles, such as, for example, heavy mobile cranes, heavy trucks with a low-loader attached for transporting a heavy-duty crane for raising the nacelle onto the top of the tower. Accordingly, it is only with extreme difficulty, and at relatively high cost that it is possible to provide the appropriate type of lifting equipment on such sites for lifting a nacelle onto a tower. There is therefore a need for a method and apparatus for raising a nacelle, and indeed, any other load onto the top of a relatively high tower which avoids the need for transporting a relatively heavy-duty crane onto the site. The present invention is directed towards providing such a method and apparatus. According to the invention there is provided a method for raising a load onto a tower, the method comprising the steps of pivotally connecting a jib to the tower about a main pivot axis with the jib extending substantially outwardly therefrom in a first orientation, a main winch rope being operably carried on the jib at a first location for raising the load, attaching the main winch rope to the load, operating the main winch rope for raising the load, pivoting the jib with the load raised thereon to a second orientation for locating the load adjacent the tower, and operating the main winch rope while the jib is in the second orientation for positioning the load onto the tower at a desired location. In one embodiment of the invention the method further comprises the step of securing the load to the tower at the desired location. Preferably, the jib is an elongated jib, and in the first orientation the jib extends sidewardly outwardly of the tower from the main pivot axis. Advantageously, the jib extends substantially horizontally when in the first orientation. Preferably, the first location at which the main winch rope is attached to the jib is located at a position spaced apart along the jib from the main pivot axis so that the main winch rope extends downwardly from the first location, substantially parallel to the tower and spaced apart therefrom for raising the load from a position on the ground which is spaced apart from the tower. Advantageously, the first location is located substantially adjacent a free end of the jib. In one embodiment of the invention the jib extends in a generally upward direction from the main pivot axis in the second orientation for locating the load above the desired location, and the main winch rope is operated for lowering the load onto the tower while the jib is in the second orientation. Advantageously, the jib extends substantially vertically above the tower from the main pivot axis in the second orientation with the load suspended from the jib above an upper platform adjacent the top of the tower, and the main winch rope is operated for lowering the load onto the upper platform while the jib is in the second orientation. Ideally, the first location is located along the jib at a distance from the main pivot axis sufficient that when the jib is in the second orientation and the load is raised, the load is suspended spaced apart from and above the desired location. In another embodiment of the invention the jib is pivotally connected to the tower towards the top thereof, and preferably, the jib is pivotally connected to the tower at a location spaced apart downwardly from the top thereof. In another embodiment of the invention a secondary winch rope is engagable with the jib at a first secondary location, for pivoting the jib from the first orientation to the second orientation, the method comprising the additional step of operating the secondary winch rope for pivoting the jib from the first orientation to the second orientation. Preferably, the first secondary location is spaced apart from the main pivot axis for inducing a turning moment in the jib for pivoting the jib from the first to the second orientation on operation of the secondary winch rope. Advantageously, the first secondary location is spaced apart from the main pivot axis on an opposite end of the jib to the end on which the first location is located, the main pivot axis being located intermediate the first location and the first secondary location. In another embodiment of the invention the secondary winch rope is engagable with the jib at a second secondary location, the second secondary location being spaced apart from the main pivot axis and being positioned so that as the jib is pivoting into the second orientation, operation of the secondary winch rope continues to induce a turning moment in the jib for pivoting the jib into the second orientation and for retaining the jib in the second orientation. Ideally the main pivot axis extends substantially horizontally. In one embodiment of the invention the jib comprises a connecting means for connecting the jib to the tower. Preferably, the connecting means is releasably connectable to the tower. Advantageously, the method further comprises the step of forming a receiving means in the tower for receiving the connecting means. In one embodiment of the invention the connecting means comprises a main shaft, and the receiving means is provided by a shaft receiving bore which extends transversely relative to the tower, and which is engagable by the main shaft. Preferably, the main shaft pivotally engages the shaft receiving bore in the tower. In another embodiment of the invention the method further comprises the step of operating the connecting means for engaging the receiving means in the tower. In another embodiment of the invention the method comprises the additional step of hoisting the jib onto the tower prior to connecting the jib to the tower. Preferably, the method comprises the step of attaching a hoisting rope to the tower for hoisting the jib from the ground onto the tower, and operating the hoisting rope for hoisting the jib onto the tower. Advantageously, the hoisting rope is attached to the tower at a location above the location at which the jib is to be pivotally connected to the tower. In a further embodiment of the invention the method comprises the additional step of removing the jib from the tower when the load has been positioned on the tower. In one embodiment of the invention the load is a component which is to be located at the desired location on the tower. In another embodiment of the invention the component is a wind powered generator. In a further embodiment of the invention the component is a nacelle. In an alternative embodiment of the invention the load is a portion of the tower which is to be raised and secured to an already erected portion of the tower for progressively erecting the tower, and the method further comprises the step of securing the just positioned portion of the tower to the erected portion of the tower, and preferably, the method comprises the steps of sequentially raising a plurality of portions of the tower and as each portion of the tower is secured to the already erected portion of the tower, connecting the jib to the just secured portion of the tower for raising the next portion of the tower. Additionally, the invention provides apparatus for raising a load onto a tower, the apparatus comprising a jib having a connecting means for connecting the jib to the tower for pivoting the jib relative to the tower about a main pivot axis from a first orientation with the jib extending outwardly of the tower to a second orientation, a main winch rope being operably carried on the jib at a first location for raising the load, and a means for pivoting the jib about the main pivot axis from the first orientation to the second orientation for locating the raised load adjacent the tower so that by operating the main winch rope while the jib is in the second orientation the load is positioned on the tower at a desired location. Preferably, the jib is an elongated jib, and the connecting means connects the jib to the tower with the jib extending sidewardly outwardly of the tower from the main pivot axis in the first orientation. Advantageously, the connecting means connects the jib to the tower so that the jib extends substantially horizontally in the first orientation. In one embodiment of the invention the connecting means connects the jib to the tower so that in the second orientation the jib extends substantially upwardly of the tower from the main pivot axis. Preferably, the jib extends substantially vertically upwardly from the main pivot axis when in the second orientation. In one embodiment of the invention the first location is positioned along the jib spaced apart from the main pivot axis so that the main winch rope extends downwardly from the first location substantially parallel to the tower and spaced apart therefrom for raising the load from a position on the ground which is spaced apart from the tower. In another embodiment of the invention the first location is located substantially adjacent the free end of the jib. Ideally, the first location is located along the jib at a distance from the main pivot axis sufficient that when the jib is in the second orientation, the raised load is suspended spaced apart from and above the desired location. In one embodiment of the invention the means for pivoting the jib from the first orientation to the second orientation comprises a secondary winch rope, the secondary winch rope being operably engagable with the jib at a first secondary location. Preferably, the first secondary location is spaced apart from the main pivot axis so that the secondary winch rope induces a turning moment in the jib for pivoting the jib from the first orientation to the second orientation. Preferably, the jib extends on opposite sides of the main pivot axis, the first location being located on one side of the main pivot axis, and the first secondary location being located on the other side of the main pivot axis. In one embodiment of the invention the first secondary location is spaced apart from the main pivot axis on an opposite end of the jib to the end on which the first location is located, the main pivot axis being located intermediate the first location and the first secondary location. In another embodiment of the invention the secondary winch rope is operably engagable with the jib at a second secondary location, the second secondary location being spaced apart from the main pivot axis and being positioned so that as the jib approaches the second orientation, the secondary winch rope continues to induce a turning moment in the jib for pivoting the jib into the second orientation, and for retaining the jib in the second orientation. Preferably, an anchoring means is provided at the second secondary location for anchoring the secondary winch rope to the jib. In another embodiment of the invention a hauling member extends substantially perpendicularly upwardly from the jib when the jib is in the first location, and the second secondary location is located on the hauling member. Preferably, the secondary winch rope is haulable downwardly when the jib is pivotally connected to the tower for pivoting the jib from the first orientation to the second orientation. Advantageously, the secondary winch rope extends from the second secondary location and passes over the first secondary location and extends downwardly from the jib from the first secondary location. Ideally, a hauling means is provided for winching the secondary winch rope for pivoting the jib from the first orientation to the second orientation. In one embodiment of the invention a secondary winch rope engaging pulley is located at the first secondary location for engaging the secondary winch rope. In one embodiment of the invention a first locating means is provided on the jib, the first locating means being engagable with the tower for locating the jib in the first orientation. Preferably, the weight of the jib is distributed so that when the jib is in the first orientation the weight of the jib and the first locating means cooperate for retaining the jib in the first orientation. In another embodiment of the invention a second locating means is provided on the jib, the second locating means being engagable with the tower for locating the jib in the second orientation. In a further embodiment of the invention a third locating means is provided on the jib, the third locating means being engagable with the tower for locating the jib in the second orientation. Preferably, a retaining means is provided on the jib, the retaining means being engagable with the tower and cooperating with one of the second or third locating means for retaining the jib in the second orientation. Advantageously, the retaining means is releasably engagable with one of the second or third locating means when the jib is in the second orientation. In one embodiment of the invention a winching means is provided for winching the main winch rope for raising the load. In another embodiment of the invention a means for operating the connecting means for connecting the jib to the tower is provided. Preferably, the means for operating the connecting means is remotely operable. In a further embodiment of the invention the connecting means comprises an elongated main shaft for engaging a receiving means in the tower. Preferably, the main shaft pivotally engages the receiving means. Advantageously, the main shaft is moveable relative to the jib from a first position disengaged from the receiving means to a second position engaging the receiving means. Ideally, an operating means is provided for moving the main shaft of the connecting means between the first and second positions. Preferably, the operating means for moving the main shaft of the connecting means comprises a ram. Preferably, the main shaft is formed by a piston rod of the ram. In one embodiment of the invention the main shaft engages the receiving means which is provided by a bore extending transversely substantially horizontally in the tower. Preferably, the connecting means is releasably connectable with the tower. Ideally, the main winch rope is operably engagable with the jib so that when the jib is in the second orientation, the main winch rope cooperates with the jib for urging the jib out of the second orientation. Preferably, the main winch rope operably engages the jib so that by tensioning the main winch rope when the jib is in the second orientation the main winch rope induces a turning moment in the jib for urging the jib out of the second orientation. In one embodiment of the invention the weight of the jib is dispersed over the jib so that on the jib being urged out of the second orientation by the main winch rope the weight of the jib acts to urge the jib into the first orientation. In another embodiment of the invention the jib comprises a pair of spaced apart jib members connected together for accommodating the tower therebetween, each jib member having a first location and a first secondary location. Preferably, the connecting means is mounted on one of the jib members and is engagable with the other of the jib members. Advantageously, one hauling member extends from each jib member. Preferably, the jib members are moveable towards and away from each other for accommodating varying cross-sections of the tower, and an urging means for moving the jib members towards and away from each other is provided. Advantageously, each locating means extends between the respective jib members. In one embodiment of the invention the urging means for moving the jib members towards and away from each other is remotely operable. In a still further embodiment of the invention a hoisting means is provided for hoisting the jib onto the tower. Preferably, the hoisting means is attached to the tower at a location above the location at which the jib is to be connected. In one embodiment of the invention the apparatus is adapted for raising a component from the ground onto a top platform of the tower. In another embodiment of the invention the component is a wind powered generator. In a further embodiment of the invention the apparatus is for raising a portion of the tower onto an already erected portion of the tower. Additionally, the invention provides a tower comprising the apparatus according to the invention, the apparatus being pivotally connected to the tower by the connecting means. The advantages of the invention are many. Needless to say, the main advantage of the invention is that the apparatus and method enable a load, for example, a nacelle to be raised from the ground onto the top of the tower without the need for relatively heavy and expensive lifting apparatus. It will be readily apparent that the jib of the apparatus can be relatively lightweight, and thus, can be transported onto relatively remote sites without any great difficulty. Indeed, where roads are of poor quality, and in particular where roads to the remote location are narrow it is still possible to transport the apparatus. In extreme cases, the apparatus may be of sufficiently lightweight and small size to be delivered on site by helicopter. Another advantage of the method and apparatus according to the invention is that as well as being suitable for raising a nacelle onto a tower, the method and apparatus are likewise suitable for lowering a nacelle from a tower, for example, for the purpose of carrying out maintenance work. It is envisaged that the apparatus may be retained on site on a wind farm and could be attached to the respective towers of the site as a nacelle falls due for servicing or maintenance for the purpose of lowering the nacelle from the tower onto the ground for enabling the appropriate servicing or maintenance to be carried out on the nacelle, and in turn for raising the nacelle back onto the tower, or a replacement nacelle as the case may be. In which case, it is envisaged that the hoisting means would be left in position permanently on the tower. A further advantage of the method and apparatus is that the method and apparatus may be used for progressively constructing a tower from preformed or precast portions, and as each new portion is raised, positioned and secured to the already erected portion of the tower, the apparatus is moved upwardly on the tower, and connected to the just erected portion, for the purpose of raising the next portion of the tower onto the just erected portion of the tower, or for raising a component to be mounted on the tower. A further advantage of the invention is obtained when the jib is provided by a pair of spaced apart jib members, and in particular, when the jib members are moveable towards and away from each other. This allows the jib members to be moved towards each other as the jib is being raised up the tower, in cases where the lower portion of the tower is of larger cross section than the upper portion, and also, where the tower tapers upwardly from a larger lower cross-section to a narrower upper cross-section. By providing the jib members in a form in which they are separable from each other, a particularly important advantage is obtained, in that the two jib members may be assembled to each other on the ground with the respective jib members extending on opposite sides of the tower. Additionally, the method and apparatus when used for raising a nacelle onto a top platform of a tower has the advantage that initially, the nacelle without the propeller attached thereto may be raised by the apparatus from the ground to a height which is convenient for facilitating attachment of the propeller to the nacelle without risk or danger of the propeller being damaged by hitting the ground. The nacelle with the propeller attached thereto is then raised the remaining distance to the jib, so that when the jib is pivoted from the first orientation to the second orientation the nacelle is located above the platform of the tower onto which it is to be secured. This, thus avoids the need for having to secure the propeller to the nacelle after it has been secured to the tower. A further advantage of the method and apparatus according to the invention is that the method and apparatus may be used for disassembling a tower in portions sequentially, commencing with the top most portion of the tower, and as each portion of the tower is lowered to the ground, the apparatus is then lowered further down the tower for transferring the next upper most portion to the ground. The invention will be more clearly understood from the following description of a preferred embodiment thereof which is given by way of example only with reference to the accompanying drawings, in which: Fig. 1 is a perspective view of apparatus according to the invention in use for raising a load onto a tower, Fig. 2 is a perspective view of the apparatus of Fig. 1, Fig. 3 is a plan view of the apparatus of Fig. 1, Fig. 4 is a perspective view of a detail of the apparatus of Fig. 1, Fig. 5 is a side elevational view of a portion of the detail of Fig. 4, Fig. 6 is a enlarged perspective view of a top portion of the tower of Fig. 1, Fig. 7 is a side elevational view of the apparatus of Fig. 1 in use on the tower, Fig. 8 is a side elevational view of the apparatus of Fig. 1 also in use on the tower but illustrated in a different orientation, Fig. 9 is a perspective view of the apparatus of Fig. 1 mounted on the tower and in the orientation illustrated in Fig. 8, Fig. 10 is a perspective view of the apparatus of Fig. 1 mounted on the tower, and in the orientation of Fig. 7, Fig. 11 is an exploded perspective view of a further detail of the apparatus of Fig. 1, and Figs. 12(a) to 12(d) are side elevational views of the apparatus of Fig. 1 in various positions and orientations on the tower. Referring to the drawings there is illustrated apparatus according to the invention indicated generally by the reference numeral 1 for carrying out a method also according to the invention for raising a load, in this embodiment of the invention a nacelle wind-powered generator 2 which is illustrated in block representation from the ground 3 onto a top platform 4 of a tower 5. Such wind-powered generators 2 will be well known to those skilled in the art, and in general, they are referred to as nacelles. It is intended that the apparatus 1 will lift the wind- powered generator 2 onto the platform 4 with the propeller (not shown) of the generator 2 in place. The tower 5 is of circular transverse cross-section of reinforced concrete which is cast in situ, and extends upwardly with a gradual taper from the ground 3 to a position 6 intermediate the bottom 7 and top 8 of the tower 5. The portion of the tower 5 between the intermediate position 6 and the top 8 is of substantially constant cross-section. Such towers 5 will be well known to those skilled in the art, and typically, are constructed in a remotely located wind farm which comprises a plurality of similar towers, on the top of each of which is located a wind powered generator. The apparatus 1 comprises a jib 10 for releasably and pivotally connecting to the tower 5 adjacent the top 8 thereof by a connecting means, which in this embodiment of the invention is provided by a main shaft formed by a piston rod 12 of a ram 14 which is mounted on the jib 10. The piston rod 12 pivotally engages a receiving means in the tower 5, namely, a sleeve 15 of a suitable bearing material which is located in a horizontal bore 16, which extends transversely through the tower 5. The piston rod 12 thus defines a main pivot axis 9 about which the jib 10 is pivotal relative to the tower 5. The bore 16 is located in the tower 5 towards the top 8 but is spaced apart downwardly therefrom. The jib 10 when pivotally connected to the tower 5, is pivotal in the direction of the arrow A from a first orientation with the jib 10 extending sidewardly outwardly of the tower 5 and substantially horizontally as illustrated in Figs. 1 and 7 for raising the generator 2 from the ground to a position spaced apart from the tower 5, but towards the top 8 thereof, to a second orientation with the jib 10 extending substantially vertically upwardly of the tower 5 as illustrated in Figs. 8 and 9 for facilitating positioning and locating the generator 2 on the platform 4. The operation of the apparatus 1 for raising the generator 2 from the ground, in turn and positioning the generator 2 on the platform 4 will be described in detail below. The jib 10 comprises a pair of spaced apart jib members 20 and 21 of steel which are releasably secured together by first, second and third locating brackets 22, 23 and 24, respectively, and are moveable apart and towards each other for accommodating the varying diameter of the tower 5 as the jib 10 is being raised and lowered on the tower 5. A pair of hauling members 25 and 26 of steel are rigidly secured to and extend perpendicularly from the jib members 20 and 21, respectively, intermediate the ends thereof for facilitating pivoting of the jib 10 from the first orientation to the second orientation as will be described below. The first locating bracket 22 is rigidly connected at 27 to the hauling member 25, and is of arcuate shape for engaging the tower 5 to act as a first locating means for locating and stabilising the jib 10 in the first orientation, see Figs. 1 and 7. The weight of the jib 10 is distributed so that when the jib 10 is in the first orientation the weight of the jib induces a turning moment which urges the jib into the first orientation, and thus, the locating bracket 22 cooperates with the weight distribution in the jib 10 for retaining and locating the jib 10 in the first orientation. An end 28 of the first locating bracket 22 rigidly carries a threaded rod 29 which extends through a bore (not shown) in the hauling member 26 and is rotatable and slidable therein for accommodating relative movement between the hauling members 25 and 26 as the jib members 20 and 21 are moved relative to each other. An urging means comprising a powered nut 32 which is rotatably mounted in a housing 33 on the hauling member 26 engages corresponding threads 34 on the threaded rod 29, so that rotation of the powered nut 32 urges the hauling members 25 and 26, and in turn, the jib members 20 and 21 towards and away from each other, see in particular Figs. 2 and 5, and also Fig. 4. An electrically powered motor 35, which is carried on a mounting bracket 36 mounted on the hauling member 26, rotates the powered nut 32 for urging the hauling members 25 and 26 and the jib members 20 and 21 towards and away from each other. A gear 37 rigidly mounted on the end of a drive shaft 38 of the motor 35 engages corresponding gear teeth 39 on the periphery of the powered nut 32 for driving the powered nut 32. The second locating bracket 23 is similar to the first locating bracket 22, and similar components are identified by the same reference numerals. The second locating bracket 23 is also of arcuate shape and engages the tower 5 to act as a part of a second locating means for locating and stabilising the jib 10 in the second orientation as can be seen in Figs. 8 and 9. The second locating bracket 23 is rigidly connected to the jib member 20 at 40. An end 28 of the second locating bracket 23 carries a threaded rod 29 which extends through a bore (not shown) in the jib member 21. A powered nut 32 rotatably mounted on the jib member 21 engages the threaded rod 29. An electrically powered drive motor 35 which is mounted on the jib member 21 by a mounting bracket 41 drives the powered nut 32 of the second locating bracket 23 in synchronisation with the powered nuts 32 of the first locating bracket 22 for urging the jib members 20 and 21 towards and away from each other. The third locating bracket 24 is also similar to the first and second locating brackets 22 and 23, and similar components are identified by the same reference numerals. The second locating bracket 24 is similarly of arcuate shape and engages the tower 5 to act as a part of the second locating means for locating and stabilising the jib 10 in the second orientation as can be seen in Figs. 8 and 9. The third locating bracket 24 is rigidly connected to the jib member 20 at 45. An end 28 of the third locating bracket 23 carries a threaded rod 29 which extends through a bore (not shown) in the jib member 21. A powered nut 32 rotatably mounted on the jib member 21 engages the threaded rod 29. An electrically powered motor 35 which is mounted on the jib member 21 by a mounting bracket 42 drives the powered nut 32 of the third locating bracket 24 in synchronisation with the powered nuts 32 of the first and second locating brackets 22 and 23 for urging the jib members 20 and 21 towards and away from each other. An arcuate retaining bracket 46 retains the third locating bracket 24 in engagement with the tower 5 when the jib 10 is in the second orientation. The retaining bracket 46 is pivotally connected to the third locating bracket 24 at 48, and is pivotal from an open position illustrated in Fig. 4 for facilitating engagement of the third locating bracket 24 with the tower 5, to a closed position illustrated in, for example, Figs. 1 and 2, for retaining the jib 10 in the second orientation. A means for pivoting the retaining bracket 46 between the open and closed positions which may be provided by an hydraulic ram or an electrically powered motor, neither of which are illustrated is mounted on the jib member 20. The hydraulic ram or electrically powered motor (not shown) for pivoting the retaining bracket 46 between the open and closed position, is also arranged for retaining the retaining bracket 46 in the closed position. Additionally, a securing clasp 49 which is mounted on the end 28 of the third locating bracket 24 is operable by an hydraulic ram (not shown) for releasably securing the retaining bracket 46 in the closed position. The ram 14 which acts as an operating means for operating the connecting means, which in this case is provided by the piston rod 12 for engaging and disengaging the piston rod 12 with the sleeve 15 is mounted on the jib member 21. The piston rod 12 of the ram 14 is of sufficient length and stroke to span the distance between the jib members 20 and 21 so that when the piston rod 12 is extended fully from the ram 14, the piston rod 12 passes through the sleeve 15 in the tower 25, and releasably engages a bore 52 in the jib member 20. In this way the two jib members 20 and 21 are supported on the piston rod 12, and the jib 10 pivotally engages the sleeve 15 for pivoting of the jib 10 between the first and second orientations. A bore 53 in the jib member 21 corresponding to the bore 52 accommodates the piston rod 12 through the jib member 21. By disengaging the jib member 20 from the piston rod 12 and the three threaded rods 29 from the corresponding powered nuts 32, the jib members 20 and 21 can be separated for facilitating location thereof on the ground on respective opposite sides of the tower 5. This facilitates assembly of the jib members 20 and 21 on the ground with the tower 5 extending between the jib members 20 and 21 prior to raising the jib 10 up the tower 5, as will be described below. A pair of main winch ropes 55 for raising the generator 2 when the jib 10 is in the first orientation are passed over pulleys 56 and 57 which are rotatably carried on the jib members 20 and 21. Brackets 52 secured to the respective jib members 20 and 21 carry shafts 58 with the jib members 20 and 21 at first locations adjacent the free ends of the jib members 20 and 21. The pulleys 56 are rotatably carried on the shafts 58, and the main winch rope 55 depends downwardly from the pulleys 58 parallel to and spaced apart from the tower 5 for attaching to the generator 2 on the ground. The pulleys 57 are rotatably carried on hollow shafts 60 which are secured to the jib members 20 and 21 adjacent the bores 52 and 53, respectively, and bores 61 through the hollow shafts 60 are aligned and co-axial with the bores 52 and 53 in the jib members 20 and 21, respectively, for accommodating the piston rod 12 of the ram 14 therethrough. The main winch ropes 55 are wound onto a winding means, namely, a winch drum 62 which is secured to the ground 3 adjacent the base of the tower 5 for winching the main winch ropes 55. A first drive means comprising a drive motor (not shown) drives the winch drum 62 for winching the winch ropes 55. A means for pivoting the jib 10 from the first orientation to the second orientation comprises a pair of secondary winch ropes 65 which extend over pulleys 68 which are rotatably carried at respective first secondary locations on shafts 69 which extend from the jib members 20 and 21 at the free ends of the jib members 20 and 21 opposite to the free ends at which the pulleys 56 are located. The secondary winch ropes 65 are anchored by anchoring means, namely, anchoring brackets 66 to the hauling members 25 and 26 at second secondary locations. The secondary winch ropes 65 are wound onto a hauling means, namely, a hauling drum 67 which is mounted on the ground 3 adjacent the base of the tower 5. A second drive means, namely, a motor (not shown) is also mounted on the ground 3 for driving the hauling drum 67 for winching the secondary winch ropes 65 for in turn pivoting the jib 10 from the first orientation to the second orientation. Stay wires 76 extending between brackets 77 on the jib members 20 and 21 and the hauling members 25 and 26 strengthen the jib 10 . Although not illustrated, control circuitry is provided on the apparatus 1 for operating the motors 35 for powering the powered nuts 32 simultaneously, and control circuitry and valving, neither of which are illustrated are also provided for operating the ram 14 and the retaining bracket 46 of the third locating bracket 24. Such control circuitry will be well know to those skilled in the art. Suitable electric power cables and hydraulic supplies are provided to the apparatus 1 from the control circuits and valving for operating the jib 10 when it is pivotally mounted on the tower 5. Such cables and hydraulic hosing in general, are suspended from the apparatus 1 and hang down along the outside of the tower 5. Alternatively, the motors 35 may be operated by remote control radio signals through suitable control apparatus, and if desired instead of a ram operating the piston rod 12 for pivotally engaging the sleeve 15, a rod operated by an electrically powered motor and a power nut may be provided for engaging the sleeve 15. In which case, the entire apparatus 1 could be operated by remote control radio signals from the ground. A hoist 80 is mounted on the tower 5 for raising and lowering the apparatus 1 into position on the tower 5. The hoist 80 which is illustrated in particular in Fig. 12 comprises a horizontal beam 82 which extends transversely through the tower 5 parallel to and above the bore 16. Hoist pulleys 83 are rotatably carried on opposite ends of the beam 82 on each side of the tower 5, and a pair of hoist ropes 84 around the hoist pulleys 83 are wound onto a hoist drum 85 located at the lower end of the tower 5. The hoist ropes 84, in use, are attached to connecting brackets 86 on the respective jib members 20 and 21 between the piston rod 12 and the pulleys 56, but relatively closely to the piston rod 12 so that as the jib 10 is being raised, the jib 10 tilts at an angle of approximately 20° to the horizontal, with the end of the jib 10 carrying the pulleys 56 being above the end of the jib 10 which carries the pulleys 68 due to the weight distribution in the jib 10. In use, the apparatus 1 is located at the base of the tower 5 on the ground 3 with the piston rod 12 retracted into the ram 14. The jib members 20 and 21 are located on opposite sides of the tower 5 corresponding to the opposite ends of the bore 16, and the tower extends between the first and third locating brackets 22 and 24, respectively. The threaded rods 29 are engaged in the powered nuts 32, and the powered nuts 32 are rotated a few turns for engaging the powered nuts 32 onto the threaded rods 29. The main winch ropes 55 from the winch drum 62 are passed around the pulleys 56 and 57. The secondary winch ropes 65 from the hauling drum 67 are passed over the pulleys 68 and anchored to the anchor brackets 66. The jib 10 is thus assembled and ready for hoisting up the tower 5, see Fig. 12(a). The free ends of the hoist ropes 84 which depend from the hoist pulleys 83 are secured to the connecting brackets 86 on the corresponding jib members 20 and 21. The hoist drum 85 is operated for winching in the hoist ropes 84, for in turn, hoisting the apparatus 1 upwardly on the tower 5. The generator 2 at this stage should be supported on an appropriate stand above the ground with its propeller in place and connected to the generator 2, and when the jib 10 has been raised a sufficient distance off the ground, the winch ropes 55 are lowered from the pulleys 56 by operating the winch drum 62 for paying out the winch ropes 55, and the free ends of the winch ropes 55 are secured to the generator 2. The hoist drum 85 is further operated for hoisting the jib 10 up the remaining distance of the tower 5. As the jib 10 is being hoisted up the tower 5, the winch drum 62 and hauling drum 67 are operated for paying out the winch ropes 55 and 65 for enabling hoisting of the jib 10 without raising the generator 2 and for maintaining the jib 10 at an angle of approximately 20° during hoisting of the jib 10. The reason the generator 2 is attached to the winch ropes 55 is to provide tension in the winch ropes 55 as the jib 10 is being raised up the tower 5 for preventing disengagement of the winch ropes 55 from the pulleys 56 and 57. During hoisting of the jib 10 up the tower 5 the jib 10 inclines at an angle of approximately 20° with the end of the jib 10 carrying the pulleys 56 higher than the end of the jib 10 which carries the pulleys 68. When the jib 10 has been raised to a position adjacent the bore 16, the powered nuts 32 are operated for urging the jib members 20 and 21 towards each other so that the jib members 20 and 21 are adjacent the tower 5. The jib members 20 and 21 are aligned with the tower 5 so that the piston rod 12 is aligned with the sleeve 15 in the tower 5. When alignment has been achieved, the ram 14 is operated for extending the piston rod 12 into and through the sleeve 15 for engaging the bore 52 in the jib member 20. The jib 10 is now pivotally connected to the tower 5 and the hoist ropes 84 are slackened and may if desired be disconnected from the jib members 20 and 21. As the hoist ropes 84 are slackened, the jib 10 pivots in the direction of the arrow B under its own weight into the first orientation until the first locating bracket 22 engages the tower 5. The weight distribution of the jib 10 cooperates with the locating bracket 22 for locating and retaining the jib 10 in the first orientation. The winch drum 62 is operated for winching in the main winch ropes 55 for raising the generator 2 until the generator 2 is adjacent the jib 10, see Fig. 12(c). In this position the generator 2 is well spaced apart from the tower 5, and the hauling drum 67 is operated for winching in the secondary winch ropes 65 for pivoting the jib 10 in the direction of the arrow A about the main axis 9 from the first orientation to the second orientation, see Fig. 12(d). In the second orientation the generator 2 is positioned directly above the platform 4 of the tower 5, and is spaced apart above the platform 4. As the jib 10 pivots into the second orientation the second and third locating brackets 23 and 24, respectively, engage the tower 5 below and above the sleeve 15, respectively. While the jib 10 is being pivoted from the first to the second orientation, the retaining bracket 24 is in the open position. When the jib 10 has pivoted fully into the second orientation, the retaining bracket 46 is closed to engage the third locating bracket 24 and to engage the tower 5, thereby, securely retaining the jib 10 in the second orientation. When the jib 10 is secured in the second orientation, the winch drum 62 is operated for paying out the main winch ropes 55 for lowering the generator onto the platform 4. As the generator 2 is being lowered onto the platform 4, bolt engaging holes (not shown) in the generator 2 are aligned with corresponding bolts 78 on the platform 4 for securing the generator 2 to the platform 4, and the generator 2 is lowered onto the platform 4 with the bolts 78 engaging the bolt receiving holes in the generator 2. Nuts (not shown) are then entered onto the bolts 78 and tightened for securing the generator 2 to the platform 4. With the generator 2 secured to the platform 4, the retaining bracket 46 is pivoted into the opened position for disengaging the tower 5, and before the main winch ropes 55 are disconnected from the generator 2, the winch drum 62 is operated for winding in the main winch ropes 55 for tensioning the main winch ropes 55. The action of tensioning the main winch ropes 55, causes the main winch ropes 55 to bear on the pulleys 68 as illustrated in Figs. 8 and 12(d) for inducing a turning moment in the jib 10 for pivoting the jib 10 about the main pivot axis 9 in the direction of the arrow B out of the second orientation. Once the jib 10 has pivoted slightly out of the second orientation, the weight distribution of the jib 10 is such that the jib 10 continues to pivot in the direction of the arrow B under its own weight into the first orientation. While the jib 10 is pivoting from the second orientation to the first orientation, the hauling drum 67 is operated for paying out the secondary winch ropes 65 for facilitating pivoting of the jib 10 into the first position. Once the jib 10 commences to pivot towards the first orientation under its own weight, the winch drum 62 is operated for paying out the main winch ropes 55, likewise, for facilitating pivoting of the jib 10 in the direction of the arrow B into the first orientation. When the jib is in the first orientation, the main winch ropes 55 are disconnected from the generator 2, and the jib 10 is then ready for disconnection from the tower 5 and lowering thereof. If the hoist ropes 84 had been disconnected from the jib 10, they are again secured to the connecting brackets 86 on the jib members 20 and 21, and the ram 14 is operated for retracting the piston rod 12 for disengaging the sleeve 15. The power nuts 32 are operated for urging the jib members 20 and 21 apart. The hoist drum 85 is then operated for paying out the hoist ropes 84 for lowering the jib 10. As the jib 10 is being lowered and as the cross-sectional area of the tower 5 increases the powered nuts 32 are operated for urging the jib members 20 and 21 further apart. When on the ground, the jib members 20 and 21 are disconnected from each other by disengaging the threaded rods 29 from the powered nuts 32, and the jib members may then be removed. It is envisaged that the method and apparatus according to the invention may be used for raising any load or component onto a tower of any kind. It is also envisaged that the method and apparatus according to the invention may be used in the erection of a tower, where the tower is progressively erected using preformed sections. In such cases, the method and apparatus would be used for sequentially raising the portions of the tower onto already erected portions of the tower. As each portion of the tower is raised onto the already erected portion or portions of the tower, the just raised portion of the tower would be secured to the already erected portion of the tower. Additionally as the portions of the tower are sequentially secured to the already erected portion of the tower, the jib of the apparatus would be pivotally connected to the just secured portion of the tower for raising the next portion of the tower. It is envisaged that hoist pulleys would be provided on each portion of the tower, and hoist ropes would be provided around the hoist pulleys which would then be secured to the jib for raising the jib from its current position to its next upper position, on the just secured portion. Needless to say, an appropriate receiving means would be provided in each portion of the tower for receiving the connecting means of the jib. The receiving means may be a bore and sleeve as in the case of the case of the tower just described for receiving a shaft such as a piston rod, or alternatively, the receiving means may be stubb shafts which would extend on respective opposite sides of the tower for engaging corresponding bearings in the jib members. It will of course be appreciated that the method and apparatus may also be used for raising components of a tower which would be assembled to already assembled components of the tower for subsequent assembly of the just raised components to those already assembled, and as the tower is being progressively assembled, the jib of the apparatus would be progressively moved upwardly along the tower. While powered nuts and corresponding threaded rods have been described for urging the jib members towards and away from each other, any other suitable urging means may be provided. It will also be appreciated that any other suitable locating means besides locating brackets for locating the jib in the first and second orientations on the tower may be provided. It is also envisaged that the locating brackets may be split halfway between their respective ends, and the means for urging the jib members together may be connected to the locating bracket where they are split. For example, the threaded rod may be mounted on one half of each locating bracket, and the powered nut may be located on the other half of each locating bracket. The respective halves of the locating brackets could be rigidly connected to the respective jib members. The advantage of providing the locating bracket in two halves, one half being secured to one of the jib members, and the other half being secured to the other half of the jib member is that it would provide a more symmetrical arrangement of the jib. It is also envisaged that if the locating brackets were to be provided in two halves, the retaining bracket would also be provided in two halves, each half being pivotally connected to the corresponding half of the locating bracket, and the respective halves of the retaining bracket would be pivotal from an open to a closed position. While the winch rope has been described as giving a mechanical advantage of one to one, it is envisaged that the winch rope may be provided in a block and tackle arrangement to give a higher mechanical advantage. This would be particularly advantageous in the case of relatively heavy loads, such as, for example, relatively heavy wind powered generators, or relatively heavy sections of a tower which is being progressively constructed by the apparatus according to the invention. Although not illustrated, the free end of the piston rod may be tapered for facilitating alignment and engagement of the piston rod with the sleeve in the tower. Although not illustrated, relative adjustment between the first, second and third locating brackets and the jib members and the hauling members may be provided for providing for fine adjustment of the jib, both in the first and second orientations, and in particular, in the second orientation so that the generator is correctly aligned with the platform of the tower when the jib is in the second orientation. While the method and apparatus has been described for lifting a generator onto the top of a tower, the apparatus may be used for lifting any load onto any tower or building, and indeed, it will be appreciated that the method and apparatus may also be used for lifting a load onto a tower or building at any position thereon. It is not solely for lifting the load onto the top of the tower. For example, the method and apparatus may be used for lifting a load onto a platform or other support at a position intermediate the top and bottom of the tower. While the method and apparatus according to the invention has been described for lifting a wind-powered generator onto the top of a tower with the propeller assembled to the generator, the generator may be raised onto the top of the tower and the propeller assembled subsequently to the generator. It would of course be appreciated that any reference throughout the specification to a wind-powered generator or a generator is to be taken also as a reference to a nacelle. Additionally, while the method and apparatus has been described for raising a generator onto a tower, the apparatus and method may also be used for lowering the generator or a nacelle from the tower, and typically, to the ground. Needless to say, the apparatus and method may be used for raising and/or lowering any load to or from a tower or any other structure. The method and apparatus may also be used for raising or lowering components for use with the generator. It is also envisaged that the method and apparatus may be used for demolishing or disassembling a tower. While the tower has been described as being of concrete, the tower may be of any other suitable material or construction, for example, a lattice tower or the like. While the fixing arrangement for fixing the wind-powered generator to the top platform of the tower has been described as comprising nuts and bolts, any other suitable fixing arrangement may be used.

Claims: CLAIMS 1. A method for raising a load (2) onto a tower (5), characterised in that the method comprises the steps of pivotally connecting a jib (10) to the tower (5) about a main pivot axis (9) with the jib (10) extending substantially outwardly therefrom in a first orientation, a main winch rope (55) being operably carried on the jib (10) at a first location (56) for raising the load (2), attaching the main winch rope (55) to the load (2), operating the main winch rope (55) for raising the load (2), pivoting the jib (10) with the load (2) raised thereon to a second orientation for locating the load (2) adjacent the tower (5), and operating the main winch rope (55) while the jib (10) is in the second orientation for positioning the load (2) onto the tower (5) at a desired location (4). 2. A method as claimed in Claim 1 characterised in that the method further comprises the step of securing the load (2) to the tower (5) at the desired location. 3. A method as claimed in Claim 1 or 2 characterised in that the jib (10) is an elongated jib (10), and in the first orientation the jib (10) extends sidewardly outwardly of the tower (5) from the main pivot axis (9). 4. A method as claimed in any preceding claim characterised in that the jib (10) extends substantially horizontally when in the first orientation. 5. A method as claimed in any preceding claim characterised in that the first location (56) at which the main winch rope (55) is attached to the jib (10) is located at a position spaced apart along the jib (10) from the main pivot axis (9) so that the main winch rope (55) extends downwardly from the first location (56), substantially parallel to the tower (5) and spaced apart therefrom for raising the load (2) from a position on the ground (3) which is spaced apart from the tower (5). 6. A method as claimed in any preceding claim characterised in that the first location (56) is located substantially adjacent a free end of the jib (10) . 7. A method as claimed in any preceding claim characterised in that the jib (10) extends in a generally upward direction from the main pivot axis (9) in the second orientation for locating the load (2) above the desired location, and the main winch rope (55) is operated for lowering the load (2) onto the tower (5) while the jib (10) is in the second orientation. 8. A method as claimed in any preceding claim characterised in that the jib (10) extends substantially vertically above the tower (5) from the main pivot axis (9) in the second orientation with the load (2) suspended from the jib (10) above an upper platform (4) adjacent the top (8) of the tower (5), and the main winch rope (55) is operated for lowering the load (2) onto the upper platform (4) while the jib (10) is in the second orientation. 9. A method as claimed in any preceding claim characterised in that the first location (56) is located along the jib (10) at a distance from the main pivot axis (9) sufficient that when the jib (10) is in the second orientation and the load (2) is raised, the load (2) is suspended spaced apart from and above the desired location (4) . 10. A method as claimed in any preceding claim characterised in that the jib (10) is pivotally connected to the tower (5) towards the top (8) thereof. 11. A method as claimed in Claim 10 characterised in that the jib (10) is pivotally connected to the tower (5) at a location (16) spaced apart downwardly from the top (8) thereof. 12. A method as claimed in any preceding claim characterised in that a secondary winch rope (65) is engagable with the jib (10) at a first secondary location (68), for pivoting the jib (10) from the first orientation to the second orientation, the method comprising the additional step of operating the secondary winch rope (65) for pivoting the jib (10) from the first orientation to the second orientation. 13. A method as claimed in Claim 12 characterised in that the first secondary location (68) is spaced apart from the main pivot axis (9) for inducing a turning moment in the jib (10) for pivoting the jib (10) from the first to the second orientation on operation of the secondary winch rope (65). 14. A method as claimed in Claim 13 characterised in that the first secondary location (68) is spaced apart from the main pivot axis (9) on an opposite end of the jib (10) to the end on which the first location (56) is located, the main pivot axis (9) being located intermediate the first location (56) and the first secondary location (68). 15. A method as claimed in any of Claims 12 to 13 characterised in that the secondary winch rope (65) is engagable with the jib (10) at a second secondary location (66), the second secondary location (66) being spaced apart from the main pivot axis (9) and being positioned so that as the jib (10) is pivoting into the second orientation, operation of the secondary winch rope (65) continues to induce a turning moment in the jib (10) for pivoting the jib (10) into the second orientation and for retaining the jib (10) in the second orientation. 16. A method as claimed in any preceding claim characterised in that the main pivot axis (9) extends substantially horizontally. 17. A method as claimed in any preceding claim characterised in that the jib (10) comprises a connecting means (12,14) for connecting the jib (10) to the tower (5). 18. A method as claimed in Claim 17 characterised in that the connecting means (12,14) is releaseably connectable to the tower (5). 19. A method as claimed in Claim 17 or 18 characterised in that the method further comprises the step of forming a receiving means (15,16) in the tower (5) for receiving the connecting means (12,14). 20. A method as claimed in Claim 19 characterised in that the connecting means (12,14) comprises a main shaft (12), and the receiving means (15,16) is provided by a shaft receiving bore (16) which extends transversely relative to the tower (5), and which is engagable by the main shaft (12). 21. A method as claimed in Claim 20 characterised in that the main shaft (12) pivotally engages the shaft receiving bore (15,16) in the tower (5) . 22. A method as claimed in any of Claims 17 to 21 characterised in that the method further comprises the step of operating the connecting means (12,14) for engaging the receiving means (15,16) in the tower (5) . 23. A method as claimed in any preceding claim characterised in that the method comprises the aditional step of hoisting the jib (10) onto the tower (5) prior to connecting the jib (10) to the tower (5) . 24. A method as claimed in Claim 23 characterised in that the method comprises the step of attaching a hoisting rope (84) to the tower (5) for hoisting the jib (10) from the ground onto the tower (5), and operating the hoisting rope (84) for hoisting the jib (10) onto the tower (5) . 25. A method as claimed in Claim 24 characterised in that the hoisting rope (84) is attached to the tower (5) at a location (82) above the location (16) at which the jib (10) is to be pivotally connected to the tower (5) . 26. A method as claimed in any preceding claim characterised in that the method comprises the additional step of removing the jib (10) from the tower (5) when the load (2) has been positioned on the tower (5) . 27. A method as claimed in any preceding claim characterised in that the load (2) is a component (2) which is to be located at the desired location (4) on the tower (5). 28. A method as claimed in Claim 27 characterised in that the component (2) is a wind powered generator (2). 29. A method as claimed in Claim 27 or 28 characterised in that the component (2) is a nacelle (2). 30. A method as claimed in any of Claims 1 to 26 characterised in that the load (2) is a portion of the tower (5) which is to be raised and secured to an already erected portion of the tower (5) for progressively erecting the tower (5), and the method further comprises the step of securing the just positioned portion of the tower (5) to the erected portion of the tower (5). 31. A method as claimed in Claim 30 characterised in that the method comprises the steps of sequentially raising a plurality of portions of the tower (5) and as each portion of the tower (5) is secured to the already erected portion of the tower (5), connecting the jib (10) to the just secured portion of the tower (5) for raising the next portion of the tower (5). 32. Apparatus for raising a load (2) onto a tower (5) characterised in that the apparatus comprises a jib (10) having a connecting means (12,14) for connecting the jib (10) to the tower (5) for pivoting the jib (10) relative to the tower (5) about a main pivot axis (9) from a first orientation with the jib (10) extending outwardly of the tower (5) to a second orientation, a main winch rope (55) being operably carried on the jib (10) at a first location (56) for raising the load (2), and a means (65) for pivoting the jib (10) about the main pivot axis (9) from the first orientation to the second orientation for locating the raised load (2) adjacent the tower (5) so that by operating the main winch rope (55) while the jib (10) is in the second orientation the load (2) is positioned on the tower (5) at a desired location (4). 33. Apparatus as claimed in Claim 32 characterised in that the jib (10) is an elongated jib (10), and the connecting means (12,14) connects the jib (10) to the tower (5) with the jib (10) extending sidewardly outwardly of the tower (5) from the main pivot axis (9) in the first orientation. 34. Apparatus as claimed in Claim 32 or 33 characterised in that the connecting means (12,14) connects the jib (10) to the tower (5) so that the jib (10) extends substantially horizontally in the first orientation. 35. Apparatus as claimed in any of Claims 32 to 34 characterised in that the connecting means (12,14) connects the jib (10) to the tower (5) so that in the second orientation the jib (10) extends substantially upwardly of the tower (5) from the main pivot axis (9). 36. Apparatus as claimed in any of Claims 32 to 35 characterised in that the jib (10) extends substantially vertically upwardly from the main pivot axis (9) when in the second orientation. 37. Apparatus as claimed in any of Claims 32 to 36 characterised in that the first location (56) is positioned along the jib (10) spaced apart from the main pivot axis (9) so that the main winch rope (55) extends downwardly from the first location (56) substantially parallel to the tower (5) and spaced apart therefrom for raising the load (2) from a position on the ground (3) which is spaced apart from the tower (5). 38. Apparatus as claimed in any of Claims 32 to 37 characterised in that the first location (56) is located substantially adjacent the free end of the jib (10). 39. Apparatus as claimed in any of Claims 32 to 38 characterised in that the first location (56) is located along the jib (10) at a distance from the main pivot axis (9) sufficient that when the jib (10) is in the second orientation, the raised load (2) is suspended spaced apart from and above the desired location (4). 40. Apparatus as claimed in any of Claims 32 to 39 characterised in that the means (65) for pivoting the jib (10) from the first orientation to the second orientation comprises a secondary winch rope (65), the secondary winch rope (65) being operably engagable with the jib (10) at a first secondary location (68). 41. Apparatus as claimed in Claim 40 characterised in that the first secondary location (68) is spaced apart from the main pivot axis (9) so that the secondary winch rope (65) induces a turning moment in the jib (10) for pivoting the jib (10) from the first orientation to the second orientation. 42. Apparatus as claimed in Claim 41 characterised in that the jib (10) extends on opposite sides of the main pivot axis (9), the first location (56) being located on one side of the main pivot axis (9), and the first secondary location (68) being located on the other side of the main pivot axis (9). 43. Apparatus as claimed in Claim 40 to 42 characterised in that the first secondary location (68) is spaced apart from the main pivot axis (9) on an opposite end of the jib (10) to the end on which the first location (56) is located, the main pivot axis (9) being located intermediate the first location (56) and the first secondary location (68). 44. Apparatus as claimed in any of Claims 40 to 43 characterised in that the secondary winch rope (65) is operably engagable with the jib (10) at a second secondary location (66), the second secondary location (66) being spaced apart from the main pivot axis (9) and being positioned so that as the jib (10) approaches the second orientation, the secondary winch rope (65) continues to induce a turning moment in the jib (10) for pivoting the jib (10) into the second orientation, and for retaining the jib (10) in the second orientation. 45. Apparatus as claimed in Claim 44 characterised in that an anchoring means (66) is provided at the second secondary location (66) for anchoring the secondary winch rope (65) to the jib (10). 46. Apparatus as claimed in Claim 44 or 45 characterised in that a hauling member (25,26) extends substantially perpendicularly upwardly from the jib (10) when the jib (10) is in the first location, and the second secondary location (66) is located on the hauling member (25,26). 47. Apparatus as claimed in any of Claims 40 to 46 characterised in that the secondary winch rope (65) is haulable downwardly when the jib (10) is pivotally connected to the tower (5) for pivoting the jib (10) from the first orientation to the second orientation. 48. Apparatus as claimed in Claim 47 characterised in that the secondary winch rope (65) extends from the second secondary location (66) and passes over the first secondary location (68) and extends downwardly from the jib (10) from the first secondary location (68). 49. Apparatus as claimed in any of Claims 40 to 48 characterised in that a hauling means (67) is provided for winching the secondary winch rope (65) for pivoting the jib (10) from the first orientation to the second orientation. 50. Apparatus as claimed in any of Claims 40 to 49 characterised in that a secondary winch rope engaging pulley (68) is located at the first secondary location (68) for engaging the secondary winch rope (65). 51. Apparatus as claimed in any of Claims 32 to 50 characterised in that a first locating means (22) is provided on the jib (10), the first locating means (22) being engagable with the tower (5) for locating the jib (10) in the first orientation. 52. Apparatus as claimed in any of Claims 32 to 51 characterised in that the weight of the jib (10) is distributed so that when the jib (10) is in the first orientation the weight of the jib (10) and the first locating means (22) cooperate for retaining the jib (10) in the first orientation. 53. Apparatus as claimed in any of Claims 32 to 52 characterised in that a second locating means (23) is provided on the jib (10), the second locating means (23) being engagable with the tower (5) for locating the jib (10) in the second orientation. 54. Apparatus as claimed in any of Claims 32 to 53 characterised in that a third locating means (24) is provided on the jib (10), the third locating means (24) being engagable with the tower (5) for locating the jib (10) in the second orientation. 55. Apparatus as claimed in any of Claims 32 to 54 characterised in that a retaining means (46) is provided on the jib (10), the retaining means (46) being engagable with the tower (5) and cooperating with one of the second or third locating means (23,24) for retaining the jib (10) in the second orientation. 56. Apparatus as claimed in Claim 55 characterised in that the retaining means (46) is releasably engagable with one of the second or third locating means (23,24) when the jib (10) is in the second orientation. 57. Apparatus as claimed in any of Claims 32 to 56 characterised in that a winching means (62) is provided for winching the main winch rope (55) for raising the load (2). 58. Apparatus as claimed in any of Claims 32 to 57 characterised in that a means (14) for operating the connecting means (12) for connecting the jib (10) to the tower (5) is provided. 59. Apparatus as claimed in Claim 58 characterised in that the means (14) for operating the connecting means (12) is remotely operable. 60. Apparatus as claimed in Claim 58 or 59 characterised in that the connecting means (12,14) comprises an elongated main shaft (12) for engaging a receiving means (15,16) in the tower (5). 61. Apparatus as claimed in Claim 60 characterised in that the main shaft (12) pivotally engages the receiving means (15,16). 62. Apparatus as claimed in Claim 60 or 61 characterised in that the main shaft (12) is moveable relative to the jib (10) from a first position disengaged from the receiving means (15,16) to a second position engaging the receiving means (15,16). 63. Apparatus as claimed in any of Claims 60 to 62 characterised in that an operating means (14) is provided for moving the main shaft (12) of the connecting means (12,14) between the first and second positions. 64. Apparatus as claimed in any of Claims 60 to 63 characterised in that the operating means (14) for moving the main shaft (12) of the connecting means comprises a ram (14). 65. Apparatus as claimed in Claim 64 characterised in that the main shaft (12) is formed by a piston rod (12) of the ram (14). 66. Apparatus as claimed in any of Claims 60 to 65 characterised in that the main shaft (12) engages the receiving means (15,16) which is provided by a bore (16) extending transversely substantially horizontally in the tower (5). 67. Apparatus as claimed in any of Claims 58 to 66 characterised in that the connecting means (12,14) is releasably connectable with the tower (5) . 68. Apparatus as claimed in any of Claims 32 to 67 characterised in that the main winch rope (55) is operably engagable with the jib (10) so that when the jib (10) is in the second orientation, the main winch rope (55) cooperates with the jib (10) for urging the jib (10) out of the second orientation. 69. Apparatus as claimed in Claim 68 characterised in that the main winch rope (55) operably engages the jib (10) so that by tensioning the main winch rope (55) when the jib (10) is in the second orientation the main winch rope (55) induces a turning moment in the jib (10) for urging the jib (10) out of the second orientation. 70. Apparatus as claimed in Claim 68 or 69 characterised in that the weight of the jib (10) is dispersed over the jib (10) so that on the jib (10) being urged out of the second orientation by the main winch rope (55) the weight of the jib (10) acts to urge the jib (10) into the first orientation. 71. Apparatus as claimed in any of Claims 32 to 70 characterised in that the jib (10) comprises a pair of spaced apart jib members (20,21) connected together for accommodating the tower (5) therebetween, each jib member (20,21) having a first location (56) and a first secondary location (68). 72. Apparatus as claimed in Claim 71 characterised in that the connecting means (12,14) is mounted on one of the jib members (20,21) and is engagable with the other of the jib members (20,21). 73. Apparatus as claimed in Claim 71 or 72 characterised in that one hauling member (25,26) extends from each jib member (20,21). 74. Apparatus as claimed in any of Claims 71 to 73 characterised in that the jib members (20,21) are moveable towards and away from each other for accommodating varying cross-sections of the tower (5), and an urging means (32) for moving the jib members (20,21) towards and away from each other is provided. 75. Apparatus as claimed in Claim 74 characterised in that the urging means (32) for moving the jib members (20,21) towards and away from each other is remotely operable. 76. Apparatus as claimed in any of Claims 70 to 75 characterised in that each locating means (22,23,24) extends between the respective jib members (20,21). 77. Apparatus as claimed in any of Claims 32 to 76 characterised in that a hoisting means (84) is provided for hoisting the jib (10) onto the tower (5) . 78. Apparatus as claimed in Claim 77 characterised in that the hoisting means (84) is attached to the tower (5) at a location (82) above the location (16) at which the jib (10) is to be connected. 79. Apparatus as claimed in any of Claims 32 to 78 characterised in that the apparatus (1) is adapted for raising a component (2) from the ground onto a top platform (4) of the tower (5). 80. Apparatus as claimed in Claim 79 characterised in that the component (2) is a wind powered generator (2). 81. Apparatus as claimed in any of Claims 32 to 80 characterised in that the apparatus (1) is for raising a portion of the tower (5) onto an already erected portion of the tower (5). 82. A tower comprising the apparatus as claimed in any of Claims 32 to 81 the apparatus (1) being pivotally connected to the tower (5) by the connecting means (12,14).

Inventors: TYMON MICHAEL FINBAR, TYMON, MICHAEL, FINBAR
Applicants: TYMON CORP LIMITED, TYMON MICHAEL FINBAR, TYMON CORPORATION LIMITED, TYMON, MICHAEL, FINBAR
Application year: 1996
Main classification: B66C23
IPC codes: B66C23, F03D1