Patent Publication Number: US-2011073409-A1

Title: Support platform for workers dealing with maintenance and construction of means of transport

Description:
The present invention relates to a support platform for workers dealing with maintenance and construction of a means of transport, like a craft, a railway car, a locomotive, an aeroplane, a lorry or the like. 
     Without becoming lost in generalities, in the rest of the present description we shall refer to the ship building field, even if the teachings of the present invention are also applicable to the construction/repair of other means of transport like railway cars, locomotives, aeroplanes, etc. 
     It is known how means of transport, for example water craft, need frequent ordinary and extraordinary maintenance operations to be performed. For this purpose in shipyards repair basins are prepared where the craft in need of repair is placed whenever interventions of a certain intensity have to be carried out, i.e. requiring the help of special infrastructures or a specialised workforce. 
     Of particular importance is the restoration/replacement of the external components of the plating or of parts of the propulsor apparatus like propeller shafts and propellers, rudders, etc. This is firstly because such components are subject to greater wear, and therefore require more frequent and numerous repairs. Secondly, it is because these components are generally more critical from the point of view of safety of travel of the craft. Finally, it is because they create greater logistic difficulties, due both to the need to work a certain height from the ground and the need to use complex and bulky machinery/instruments. 
     Normally, in shipyards scaffolding is used that is made through assembly of metallic tubes. Otherwise lifting electric walkways for construction use are used that almost always need to be fixed to the wall. The use of such apparatuses in shipyards has proven to be particularly dangerous because the specialised worker very often has to perform complex tasks (cutting, welding, surfacing, etc.) that can be the cause of falls with even mortal outcomes. 
     In the ship building field there is therefore a great need to have equipment able to facilitate the task of workers, allowing them to work with the greatest ease and in maximum safety on all external parts of the hull of the craft. 
     Therefore, the main purpose of the present invention is to fully satisfy the aforementioned requirement, in particular providing a platform that, through an original combination of its components, is capable of substantially improving the quality of the maintenance work on the outside of the craft, increasing the productivity of the repair work and at the same time increasing safety. 
     According to the present invention a support platform is thus made for workers dealing with maintenance of a means of transport, in accordance with the attached claims. 
    
    
     
       The present invention will now be described with reference to the attached drawings, which illustrate some non-limiting example embodiments thereof, in which: 
         FIG. 1  is a plan view of a platform subject of the present invention brought up alongside a bow of a water craft; 
         FIG. 2  is a plan view of the platform of  FIG. 1 , this time brought up alongside a stern of a water craft; 
         FIGS. 3A ,  3 B,  3 C are side views, in different configurations, of at least one pair of platforms subject of the invention brought up alongside the two sides of a water craft; 
         FIGS. 4A ,  4 B,  4 C are views (front, plan and side, respectively) of a first embodiment of a platform according to the invention with a walkway in completely lowered position; 
         FIGS. 5A ,  5 B,  5 C are views (front, plan and side, respectively) of the first embodiment of  FIGS. 4A ,  4 B,  4 C with the walkway in completely raised position; 
         FIGS. 6A ,  6 B,  6 C are views (front, plan and side, respectively) of the first embodiment of  FIGS. 4A ,  4 B,  4 C and  FIGS. 5A ,  5 B,  5 C with the walkway in completely raised position and with short planes, which constitute such a walkway, in completely extended position; 
         FIGS. 7A ,  7 B,  7 C are views (front, plan and side, respectively) of a second embodiment of a platform according to the invention with a walkway in completely raised position and with short planes, which constitute such a walkway, in completely extended position; 
         FIG. 8A  illustrates a side view of a pack of short planes, which form a walkway, piled on top of one another; 
         FIG. 8B  shows a front view of the pack of short planes of  FIG. 8A ; 
         FIGS. 9A ,  9 B show views (side and front, respectively) of a pack of short planes in a completely extended configuration; 
         FIG. 10  illustrates an exploded view of a pair of short planes; 
         FIG. 11  shows the situation in which the top short plane stays still, whereas the other short planes are located in extended position piled one on top of the other; 
         FIG. 12  illustrates the condition in which the top short plane stays still, whereas two short planes are located in extended position; moreover, it should be noted that the pack of the remaining piled up short planes stays below the second short plane in extended position; and 
         FIG. 13  shows the situation in which the top short plane stays still, whereas two short planes are located in extended position; moreover, it should be noted that the pack of the remaining piled up short planes is below the third short plane in extended position. 
     
    
    
     In the attached figures reference numeral  100  wholly indicates a support platform for workers dealing with maintenance of a means of transport, in particular of a water craft (NT). 
     In particular, in  FIG. 1  the platform  100  is shown brought up to the side of the bow (PR) of the craft (NT), whereas in  FIG. 2  the same platform  100  has been illustrated brought up to the side of the stern (PP) of the same water craft (NT). 
     As can be seen from the comparison between  FIGS. 1 and 2 , a walkway (PDN) in the two conditions takes up different configurations to “copy”, so to say, the profile of the side up to which it has been brought. 
     Moreover, in the repair of hulls of water crafts, it must be kept in mind that such hulls have extremely complex shapes, designed according to the most widely varying technical requirements. In fact,  FIGS. 1 and 2  show the level curve (CL) to which an outer edge (BE) of the walkway (PDN) must be adapted each time, according to the height from the ground of the walkway (PDN) itself. 
     With reference to  FIGS. 3A to 6C , the platform  100  according to the present invention comprises a base carriage  1 , mobile on wheels (not shown) distributed on a pair of axles (not illustrated), one of which is motorised. Preferably, like in the illustrated example, the wheels move on rails (not shown) formed adjacent, and parallel, to the position occupied by the water craft under repair, for example a shipyard basin. 
     Alternatively, the carriage  1  can be supported by tyres (not illustrated). Moreover, the two front sides of the carriage  1 , i.e. those corresponding to the fronts in the direction of travel, are provided with end stop devices (not illustrated), with anti-collision safety function. 
     In order to increase the stability of the platform  100  at least one pair of feet (PD) is provided that are extended when needed. 
     Two uprights  2  project up from the sides  1 A of the carriage  1 , from which uprights  2  a bracket structure  3  extends horizontally, above the carriage  1 . The bracket structure  3  is slidably supported by the uprights  2 , so as to be able to be raised and lowered as desired under the action of a system fed by an oil-hydraulic, pneumatic, electric or mechanical circuit by rack and pinion, worm screws, chains and cables, not represented in detail but in any case with obvious configuration for a man skilled in the art. 
     The bracket structure  3  in turn supports the said walkway (PDN), intended to support the workers dealing with maintenance and for this purpose it is equipped with perimeter railings  4  ( FIG. 4A ) to prevent them from accidentally falling. 
     The walkway (PDN), in accordance with the bracket structure  3 , can have a greater or lesser width than the carriage  1 . 
     As shall be seen more clearly hereafter, the walkway (PDN) comprises a plurality of short planes (from  9 A to  9 G) stacked on top of one another that can translate horizontally, separately from one another, and in a direction normal to a direction of advance movement (according to a double-pointed arrow (F)) of the carriage  1 . 
     As shall be seen more clearly hereafter, the short planes  9 A- 9 G are moved horizontally to “copy” as much as possible the profile of the hull. 
     The short planes  9 A- 9 G are provided with a pneumatic sensitive edge (made on the outside from rubber or another material) that prevents violent collision against the surface of the water craft, the aeroplane, the rail vehicle or other, and that can be connected to the control system in order to shut down the system. 
     As we shall see, the moving of the short planes  9 A- 9 G, through suitable actuator means, also provides the oil-hydraulic, mechanical or electric circuit with the various systems quoted above. 
     The workers working on the walkway (PDN) need means for supplying the tools/instruments commonly used for repair/maintenance. For this purpose, the platform  100  according to the invention is connected to circuits for supplying resources like, typically, oxygen, combustible gas, oil, compressed air, water and electricity, and the latter can also be intended to feed the propulsion of the platform  100  and its parts. 
     As can be clearly seen in particular in  FIG. 4A , the connection is made, in a known way, through catenaries  5  for containing the cables/pipes. 
     The platform  100  also comprises at least one retractable stair (SC) and at least one control station (CC) for controlling the raising/lowering of the bracket structure  3 , and therefore of the walkway (PDN). 
     It should also be noted that the control station (CC), provided with a suitable network of sensors that, according to what is per se obvious to the man skilled in the art, manages the programmed logic of the movements of the platform  100 . 
     Regarding this, it must be noted that, in order to avoid the possibility of damages to the water craft (NT), the management system of the control station (CC) prevents the actuation of the bracket structure  3  when the walkway (PDN) is in the extended position. 
     One or more operating points (OP) are provided on the bracket structure  3 , which are fed through electrical mains and/or hydraulic circuits, etc. To enable the workers to work at the same time at different points of the walkway (PDN) on the same side of the water craft (NT). 
     It should also be noted how the movement of the carriage  1  and the raising of the bracket structure  3  (and therefore of the walkway (PDN)) allows the workers to work with maximum ease and safety at any height and in any longitudinal location with respect to the side of the water craft (NT). 
     The positioning of the bracket structure  3  at the desired height necessarily takes place with the short planes  9 A- 9 G of the walkway (PDN) in withdrawn position ( FIGS. 4B ,  5 B), to avoid any risk of collision with the side of the water craft (NT). 
     When the bracket structure has reached the desired height it is possible to extend one or more short planes  9 A- 9 G towards the side of the water craft (NT) ( FIG. 6B ) to configure its outer edge (BE) to the profile of the hull that, as stated previously, in general changes according to the height and according to the specific location on the side. 
     In order to ensure that the edge (BE) gets as close as possible to the profile of the hull it has proven very useful to use substantially triangular or trapezoidal appendices (AP 1 ), (AP 2 ) ( FIG. 6B ), each of which is pivoted in a respective hinge (CR 1 ), (CR 2 ) fixedly connected to the last short plane (for example  9 C in the embodiment shown in  FIG. 6A ). 
     The appendices (AP 1 ), (AP 2 ) are also provided with a pneumatic sensitive edge that prevents violent collision against the surface of the means of transport (NT) and that is electrically connected to the command station (CC) in order to shut down the system. 
     The worker, after having extended all of the short planes  9 A- 9 G that follow the profile of the hull of the water craft (NT) (with the system that shall be described in greater detail hereafter), in order to fill possible empty spaces remaining between the last extended short plane  9 A- 9 G and the profile of the hull itself, mechanically or manually rotates at least one appendix (AP 1 ), (AP 2 ) around its hinge (CRN 1 ), (CRN 2 ) by an angle such as to follow the curved profile of the hull as closely as possible. After this operation the worker fixes (with known means that are not shown) the position of the appendices (AP 1 ), (AP 2 ) involved. 
     It should also be noted that both the outer edges of the short planes  9 A- 9 G, and those of the appendices (AP 1 ), (AP 2 ) are rectilinear, whereas the profiles of the hulls generally have a curvilinear extension. Therefore, there cannot be perfect “copying” of the outer edge (BE) on the actual profile of the side of the hull, but the approximation is still acceptable and safe for the users of the platform  100 . 
     With reference to  FIGS. 7A-7C , a second embodiment of the walkway (PDN)* has been shown. Such a walkway (PDN)* comprises a short plane  9 A* that extends practically for the entire length of the bracket structure  3 , and a series of short planes  9 B*,  9 B**,  9 C* that have an extension in length of about half (as illustrated in  FIG. 7B ), or in any reduction ratio with respect to the short plane  9 A*. As usual, a short plane  90 * is provided with an appendix (AP 1 )* pivoted to a hinge (CRN 1 )*, whereas a short plane  9 B** is provided with an appendix (AP 2 )* pivoted to a hinge (CRN 2 )*. 
     In the second embodiment shown in  FIGS. 7A-7C  the system for moving the short planes  9 B*,  9 B**,  9 C* is more complex and expensive than that for the short planes  9 B,  9 C of the first embodiment illustrated previously with reference to  FIGS. 6A-6C , but the second solution ( FIGS. 7A-7C ) is more “flexible” in the sense that the outer edge (BE) of the short planes  9 B*,  9 B**,  9 C* (possibly in concert with the appendices (AP 1 )*, (AP 2 )*) more closely approximates the profile of the hull. 
     As shown in the rest position of  FIGS. 8A ,  8 B, the walkway (PDN) comprises a plurality of short planes  9 A- 9 G stacked on top of one another. 
     Of course, in the rest configuration of  FIG. 8A  only the short plane  9 A can actually be used by the workers on the platform. Therefore, in this case, the surface of the walkway (PDN) coincides with a walkable surface  10 A of the short plane  9 A. The remaining short planes  9 B- 9 G are covered by the short plane  9 A and thus, in the configuration of  FIG. 8A , cannot be walked upon by the workers working on the platform  100 . 
     As shown in greater detail in  FIGS. 9A ,  9 B,  10 , each walkable short plane  9 B- 9 G comprises a relative bearing structure (SP) on which a respective walkable surface  10 B,  10 B,  10 C, etc. is fixed. 
     In turn, each bearing structure (SP) comprises a beam  11  of the HE type (UNI — 5397-64), commonly known as “double T beam” where the two horizontal flanges  11 A and  11   b  respectively have a height practically equal to that of the vertical central web  110  ( FIG. 8B ). Such a bearing structure can be made, as an alternative to the double T beam, also with profiles of another type and shape suitable for the intended purpose. 
     A vertical plate  12  that is the ideal downward continuation of the vertical central web  11 C of the beam  11  ( FIG. 10 ) is fixed onto the lower horizontal flange  11 B of the beam  11  (for example by welding). The vertical plate  12  has a shorter length than that of the beam  11 . Moreover, as shown again in  FIG. 10 , an edge  12 * of the plate  12  is flush with an edge  11 * of the beam  11 . Both of the edges  12 * and  11 * face towards the means of transport under repair. 
     As shown in  FIG. 8B , the bearing structures (SP 1 ), (SP 2 ) of the two short planes  9 C,  9 D are vertically staggered so that the beam  11  of the bearing structure (SP 2 ) of the short plane  9 D faces the plate  12  relative to the bearing structure (SP 1 ) of the short plane  9 C. Moreover, between the vertical web  11 C of the bearing structure (SP 2 ) and the vertical plate  12  of the bearing structure (SP 1 ) a double T-shaped intermediate beam  13  is inserted. 
     The intermediate beam  13 , in turn, comprises two horizontal flanges  13 A,  13 B separated by a vertical web  13 C. The intermediate beam  13  can also be formed from a commercial preformed profile or welded and worked. 
     Moreover, as shown in  FIG. 10 , between a face  12 ** of the plate  12  of the bearing structure (SP 1 ) and a first face  13   c * of the web  13   c  of the intermediate beam  13  there is a pair of wheels (WL 1 ), (WL 2 ), each having its own rotation axle (AXL 1 ), (AXL 2 ) fixed with respect to the plate  12 . 
     Similarly, between a second face  13 C** of the web  13   c  of the intermediate beam  13  there is a pair of wheels (WL 3 ), (WL 4 ) each having its own rotation axle (AXL 3 ), (AXL 4 ) fixed with respect to the web  11   c  of the beam  11  belonging to the bearing structure (SP 2 ). Moreover, the wheels (WL 1 )-(WL 4 ), in the described system, have the function of shouldering and resisting the lateral thrusts. 
     The operation of the translation mechanism of the short planes  9 B- 9 G is the following:
         if, for example, an actuator (not shown) pushes the short plane  9 D horizontally (and therefore pushes its relative bearing structure SP 2 ), the relative beam  11  and the relative plate  12  move horizontally, rolling with the wheels (WL 3 ) and (WL 4 ) on the guide consisting of the face  13   c ** of the intermediate beam  13  and the side inner parts of the flanges  13 A,  13 B;   the movement of the beam  11  and of the plate  12  of the bearing structure SP 2  continues until a wheel (WL 4 )* ( FIG. 10 ) (which is located at the plate  12  of the bearing structure SP 2 ) goes into abutment against an end stop provided on the track made on the face  13 C** belonging to a bearing structure (SP 3 );   therefore, by continuing to push on the short plane  9 D the intermediate beam  13 , which is located between the bearing structure (SP 2 ) of the short plane  9 D and the bearing structure (SP 3 ) of the short plane  9 E, also starts to be pulled horizontally;   the horizontal pulling of the intermediate beam  13 * translates into a horizontal pulling of the short plane  9 E and also of all of the other short planes  9 F,  9 G due to the concatenation that exists with the other bearing structures (for example SP 4 ), which, however, are located below the surface  10 D and therefore cannot be walked upon; in any case, as shown in  FIG. 13 , the total walkable surface of the walkway (PDN) is given by the sum of the usable portions of the walkable surfaces  10 A,  10 B,  10 C,  10 D;   by acting now with another actuator (not shown) on the short plane  9 E, a portion of the walkable surface  10 E will project and thus in this way it shall be possible to extend the total walkable surface facing towards the means of transport (water craft, rail wagon, locomotive, aeroplane and the like) to be repaired or constructed; the underlying short planes  9 F and  9 G shall be pulled with the same mechanism seen previously; of course, their surfaces cannot be walked upon ( FIG. 13 ).       

     Although in  FIGS. 8A ,  8 B,  9 A,  9 B,  11 ,  12 ,  13  short planes  9 B- 9 G have been shown that each descend with respect to the previous one, it is possible to consider different solutions, like those illustrated with reference to  FIGS. 3A ,  3 B,  3 C,  6 C,  7 C, in which each short plane  9 B- 9 G is in raised position with respect to the previous one. This is obtained, obviously, by taking the short plane  9 G as the first short plane, instead of the short plane  9 A (as shown, on the other hand, in  FIGS. 8A ,  8 B,  9 A,  9 B,  11 ,  12 ,  13 ). 
     It can easily be understood how the platform according to the invention fully achieves the predetermined purpose, in practice by providing a mobile production area, easy to configure to satisfy any specific positioning requirement of the workers with respect to the means of transport to be repaired or constructed. Moreover, it is able to provide the workers themselves with the resources needed for the most widely varying types of intervention, even the most qualified ones. All of this with the maximum safety. The quality and productivity of the maintenance or construction work are in this way substantially increased.