Abstract:
Lifting device ( 1 ) for disabled people in wheelchairs and children&#39;s pushchairs, comprising a supporting frame ( 2 ), permanently applied to a motor vehicle or a fixed installation, and a sliding foldaway platform ( 3 ) moving between a retracted position and an extracted position, with respect to said supporting frame ( 2 ). The platform ( 3 ) can also move in said extracted position, between a lowered position and a raised position, by means of an articulated parallelogram linkage system ( 17 ). The movements of the platform ( 3 ) are achieved by means of electrical actuators ( 9, 20 ).

Description:
BACKGROUND OF THE INVENTION 
     This invention relates in general to equipment for facilitating the access of disabled people and children&#39;s pushchairs aboard motor vehicles, i.e. public transport vehicles, or more simply to fixed installations, such as public buildings, museums and similar. 
     Specifically, this invention relates to a lifting device for disabled people in wheelchairs, intended to be permanently applied to a vehicle or to a fixed installation, to overcome the difference in level between a lower station and an upper station, for accessing said vehicle or said fixed installation. 
     SUMMARY OF THE INVENTION 
     The purpose of this invention is to provide a lifting device of this type which can be fully folded away, i.e. which is included in the volume of the vehicle, or of the fixed installation, to which it is applied, until its use is required. 
     An additional purpose of this invention is to provide a particularly functional foldaway lifting device, which conformation is relatively simple and cost-effective, and which does not employ fluid actuators. 
     According to this invention, this purpose is obtained essentially thanks to the fact that the lifting device comprises: 
     a supporting frame embedded within a housing provided under said upper station of the vehicle or fixed installation, 
     a sliding foldaway platform, moving between a retracted position and an extracted position, with respect to said supporting frame, and also moving, in said extracted position, between a lowered condition, in which it rests on said lower station, and a raised condition, in which it is substantially arranged on the level of said upper station, 
     articulated parallelogram linkage means between said platform and said frame, and 
     electrical actuator control means for moving said platform between said retracted position and said extracted position and, by means of said articulated parallelogram linkage means, between said lowered condition and said raised condition. 
     According to a preferred embodiment of this invention, said platform is conveniently equipped with a front board, moving between an erected position and a folded position, in which is acts as a front slide for accessing said lower station. Furthermore, the platform can be equipped with a rear extractable extension, sliding over the platform between a retracted position and an extracted position, in which it acts as a rear slide for connecting to the upper station. Electrical actuator means for controlling the movements of said front board and said sliding extension are provided. 
     The lifting device according to this invention can be advantageously equipped with a remote control device, or magnetic card, or similar, operatively associated to the respective control device for allowing also remote activation by the user. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     This invention will be better explained by the following detailed descriptions with reference to the accompanying figure as non-limiting example, wherein: 
     FIG. 1 is a perspective schematic view shows an example of application of the lifting device according to this invention on a bus, where the lifting device is shown in an inoperative, retracted position, 
     FIG. 2 is a perspective view on a larger scale of the lifting device in the retracted position of FIG. 1, 
     FIG. 3 is a similar view to FIG. 1 with the lifting device in extracted position, 
     FIG. 4 is a similar view to that of FIG. 2 showing the lifting device in the extracted position of FIG. 3, 
     FIG. 5 is a similar view to FIG. 1 with the lifting device in lowered position, 
     FIG. 6 is a similar view to FIG. 2 showing the lifting device in the lower condition of FIG. 5, 
     FIG. 7 is a similar view to FIG. 1 showing the lifting device in lifted position with the rear extension in extracted position, 
     FIG. 8 is a similar view to FIG. 2 showing the lifting device in the lifting condition in FIG. 7, 
     FIG. 9 is a perspective partial view on an exploded, larger scale of a detail of the platform of the lifting device, and 
     FIGS. 10 and 11 are perspective and scaled down views of two variants of the lifting device according to this invention. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The example of embodiment of the invention illustrated in the drawings refers to the application of the lifting device according to this invention on a public transport vehicle, for example a bus. It must be emphasised that the following description, expressly referred to said example of embodiment, is essentially identically applicable in the case of the application of the lifting device according to this invention to other types of vehicles, and also to fixed installations. 
     In the drawings, F refers to the floor of a bus accessible from the outside across a door D and a set of steps of which the intermediate step, located on a lower level with respect to the floor F, is indicated with S. 
     This step S presents a hollow shape and is normally closed (FIGS. 1 and 2) by the front extremity of a lifting device according to this invention, generally indicated with numeral  1 , permanently applied and folded away inside the cavity of the step S. 
     With more detailed reference to FIG. 2, the lifting device  1  essentially comprises a stationary supporting frame  2  and a mobile platform, as explained below, with respect to the supporting frame  2 . 
     The supporting frame  2  is generally U-shaped with a rear side  4  and to lateral sides  5  reciprocally connected by two transversal profiles  6 , which define two essentially C-shaped longitudinal sliding guides  7 . As better appears in FIGS. 4,  6  and  8 , a first electrical geared motor  8 , operating a worm screw system  9 , extending along one of the lateral sides  5  and which function will be explained in the following description, is fastened to the rear side  4  of the supporting frame  2 . 
     The mobile platform  3  includes two longitudinal sides  10 , consisting of contoured profiles shown in detail in FIG. 9, interconnected by a horizontal base  11  over which a structural plate  12  can be arranged, for example consisting of an embossed aluminium panel. The shape of the sides  10  is complementary to that of the guides  7  in which they slide. An enlargement  13  is arranged on a side  10  near the front side of the platform  2 . 
     This front side consists of a board  14 , which is articulated to the lower parts of the sides  10  of the platform  3  so to rock between an erected position, shown in FIGS. 1-4 and  7 ,  8 , and a folded position, shown in FIGS. 5 and 6, in which it extends essentially along the extension of the base  11 , acting as a front board  14 . A second electrical geared motor  15 , housed inside the enlargement  13 , in the way shown in FIG. 9, and a worm screw system  16  are provided to turn the front board  14  between the erected position and the folded position. 
     The lateral sides of the platform  3  are connected by means of an articulated parallelogram linkage system formed by two pairs of articulated longitudinal arms  17  and a mobile unit, generally indicated with numeral  18 , which also slides with the platform  3  along the sides  5  of the supporting frame  2 . This mobile unit  18  essentially comprises a crossbar  19 , operatively connected to the worm screw system  9 , operated by the motor  8 , which is connected to a third electrical geared motor  20  arranged essentially in central position. This geared motor operates two screw jacks  21 , arranged to multiply the torque of the motor  20 , meshing with the respective worm screws  22 , connected to a pair of respective connecting rods, or rocker arms,  23  fitted on the extremity of a transversal torsion bar  24 . Said transversal torsion bar  24  synchronises the movement of the two connecting rods  23  for controlling the two articulated parallelogram arms  17  so to obtain the downwards rotation to the position illustrated in FIGS. 5 and 6 and the upwards rotation to the position illustrated in FIGS. 7 and 8 from the horizontal configuration shown in FIGS. 1 to  4 . A lowered position of the platform  3  corresponds to the downwards rotation related to the supporting frame  2 , while the upwards rotation corresponds to a raised condition of said platform  3 . 
     The rear side of the platform  3  consists of a board  25  mobile between a closed position, shown in FIGS. 2-6, in which it extends transversally with respect to the FIGS. 7 and 8. This rear board  25  is actually formed by two pairs of articulated elements  26 ,  27 , the first of which pivots on the rear extremities of the lateral sides  10  and the second of which pivots on an extension  28  of the base  11  of the platform  3 . This extension  28  slides telescopically with respect to the base  11  between a retracted position, shown in FIGS. 2 to  6 , and an extracted position, shown in FIGS. 7 and 8, in which it acts as a rear slide for the platform  3 , according to the method illustrated below. 
     The movement of the sliding extension  28  between the retracted and extended positions is also controlled by an electrical geared motor, not illustrated in the drawings, similar to the geared motor  15  described above related to the worm screw system. 
     It must be emphasised that both the base  11  and the extension  28  may be made of multiple elements forming the respective extensible and retractable telescopic structures instead of each being made of a single element. An arrangement of this sort (schematically illustrated in FIG. 10 according to the base  11  of the platform  3 ) considerably reduces the volume of the lifting device  1 . 
     The electrical actuators described above are connected to a control unit, not illustrated in the drawings because known by experts of the sector, for controlling the operation according to a sequential phased cycle. For controlling this cycle, the lifting device  1  according to the invention is conveniently equipped with a remote control unit, for example of the type indicated by numeral  29  in the drawings. This unit may consist of an equivalent remote control device, also of the type employing a magnetic card (as schematically shown in FIG.  11 ), radio-frequency or infrared remote control, or similar. 
     The control logic of the lifting device  1  according to this invention can acknowledge the presence of the disabled person aboard. The system arranges and operates the devices normally provided aboard vehicles for safely fastening the wheelchair, which may also fold away to avoid hindrance and obstacles to passengers when no disabled person is aboard. 
     The operation of the lifting device is described below. 
     Normally, i.e. when its use is not required, the lifting device  1  is completely folded away inside the step S. 
     When a disabled person in a wheelchair requires use, by means of the remote control  29  or similar control device, firstly the geared motor  8  is activated which, via the worm screw unit  9 , makes unit  18 —and, consequently, the platform  3 —slide with respect to the supporting frame  2  from the retracted position of FIGS. 1 and 2 to the extracted position of FIGS. 3 and 4. In this way, the platform  3  is folds out from inside the frame  2  and, consequently, from the step S, with the arms  17  of the articulated parallelogram systems horizontal, the front board  14  erect and the rear board  25  closed. 
     From this position, the operation of the geared motor  20  causes the downwards rotation of the arms  17  in the articulated parallelogram system, by means of the connecting rods  23  and the torsion bar  24 , to rest the platform  2  on the ground, indicated with reference G, i.e. on the disabled person&#39;s level. Having reached this position (FIGS.  5  and  6 ), the geared motor  15  controls, via the worm screw system  16 , the rotation of the front board  14  from the raised position to the lowered position shown in FIGS. 5 and 6, so to form a slide or ramp allowing comfortable access of the wheelchair on the platform  3 . 
     Consequently, the front board  14  is returned to the lifted position, and the geared motor  20  is operated again to the control the upwards rotation of the arms  17  of the articulated parallelogram system, so to arrange the platform  3  in the raised position shown in FIGS. 7 and 8. In this position, the platform  3  is arranged essentially on the level of the floor F of the bus, or on a slightly higher level. To allow the passage of the wheelchair from the platform  3  to the floor F, the extension  28  is moved from the retracted position to the extracted position, illustrated in FIGS. 7 and 8, in which it acts as a rear slide connecting the platform  3  and the floor F. By effect of this movement, the articulated elements  26 ,  27  of the rear board  25  are distended, arranging essentially longitudinally, as also shown in FIGS. 7 and 8, so to allow the passage of the wheelchair, doubling as lateral guiding boards. 
     Finally, the platform  3  is returned, after the extension  28  returns to the starting position, to the retracted condition inside the supporting frame  2  and, consequently, the step S. 
     Obviously, the disabled person will be lowered to the ground level by reversing the sequence of operation described above. 
     It appears obvious that the lifting device according to this invention is extremely practical, functional and relatively simple from the construction point of view, considering that no hydraulic actuators and respective service devices are implemented. 
     Naturally, numerous changes can be implemented to the construction and forms of embodiment of the invention herein envisaged, all comprised within the context of the concept characterising this invention, as defined by the following claims. 
     As mentioned above, the lifting device according to this invention can be applied in an equally advantageous way to any type of public transport vehicle, in addition to fixed installations, such as museums, public buildings, etc.