Patent Publication Number: US-11046554-B2

Title: Stairlifts

Description:
REFERENCE TO RELATED APPLICATIONS 
     This application is a U.S. national stage application of PCT/GB2016/053242, filed Oct. 19, 2016, which claims priority from Great Britain patent application No. 1518943.4, filed Oct. 27, 2015. The entire content of both of which is incorporated herein by reference. 
     FIELD OF THE INVENTION 
     This invention relates to stairlifts and, in particular, to aspects of a chair incorporated in a stairlift assembly 
     BACKGROUND OF THE INVENTION 
     A stairlift assembly comprises a rail mounted on a staircase; a carriage mounted on the rail for movement up and down the rail; and a chair mounted on the carriage, the chair supporting a passenger as the carriage moves along the rail. The chair typically includes a seat base, a seat back, a pair of armrests, and a footrest. Given that the footrest comprises that part of the chair closest to the treads of the staircase, it is common practice to mount safety edges on the footrest. These safety edges comprise one or more displaceable pads or flaps mounted on or adjacent to the leading and trailing edges of the footrest (as the carriage moves up and down the rail) and are wired into the electrical drive circuit of the stairlift. If, in the course of a journey, a safety edge comes into contact with an obstruction on the staircase, the safety edge will be displaced, will open a switch in the drive circuit, and thus cause the carriage to stop. 
     One or more further safety edges may be provided on the underside of the footrest to cut power to the stairlift drive motor in the event a the footrest encounters an obstruction vertically below the footrest. 
     In order to leave the foot-contacting surface of the footrest unimpeded, the safety pads are typically mounted on the underside of the footrest and it is generally convenient to incorporate the safety edges and cut-out switches in a sub-structure mounted to the underside of the footrest. However, whatever the case may be, a gap will be present in the footrest assembly, between the foot-contacting surface and the safety pads or sub-structure, to allow the safety mechanisms to function. 
     The traditional footrest assembly described above is not particularly pleasing from an aesthetic viewpoint and the gap allows the intrusion of unwanted dirt, moisture and even unwanted objects that could interfere with the operation of the safety edges. These risks are significantly greater in outdoor stairlift installations. 
     It is an object of this invention to go at least some way in addressing the limitations of existing stairlift footrest assemblies as described above; or which will at least provide a novel and useful choice. 
     SUMMARY OF THE INVENTION 
     In one aspect the invention provides a footrest for a stairlift chair, said footrest having an upper surface configured to support the feet of a user, and spaced lateral edges; said footrest further including at least one safety pad with an edge adjacent to one of said lateral edges and being characterised in that flexible covering is provided which extends along said lateral edges and overlies said at least one safety pad. 
     Preferably the flexible covering extending along both lateral edges is included in a single component. 
     Preferably said lateral edges are included in a footrest periphery, said single component overlying said periphery. 
     Preferably said single component defines an underside of said footrest. 
     Preferably that part of said single component defining the underside of said footrest, is re-enforced. 
     Preferably said single component overlies edge parts of said upper surface. 
     Preferably said single component defines on said upper surface a mounting aperture to receive a finishing footrest surface component. 
     Preferably said single component is a plastics or rubber moulding. More preferably said footrest is formed from ethylene propylene diene terpolymer (EDPM). 
     In a second aspect the invention provides a stairlift chair including the footrest set forth above. 
     Many variations in the way the present invention can be performed will present themselves to those skilled in the art. The description which follows is intended as an illustration only of one means of performing the invention and the lack of description of variants or equivalents should not be regarded as limiting. Wherever possible, a description of a specific element should be deemed to include any and all equivalents thereof whether in existence now or in the future. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       One working embodiment of the invention will now be described with reference to the accompanying drawings in which: 
         FIG. 1 : shows a stairlift chair including a footrest according to the invention; 
         FIG. 2 : shows an isometric view, from above, of a footrest according to the invention; 
         FIG. 3 : shows an isometric exploded view of a number of components for forming a footrest according to the invention; 
         FIG. 4 : shows an end-sectional view through a footrest according to the invention; and 
         FIG. 5 : shows an enlarged sectional view of part of a footrest according to the invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring firstly to  FIG. 1 , a stairlift chair  5  is depicted comprising a seat base  6 , seat back  7 , a pair of spaced armrests  8  and a footrest  9 . Conventionally the footrest assembly  9  is mounted to the bottom of chair interface  10  by means of a hinge mechanism (not shown) such that the footrest may be folded up about hinge axis  11 , substantially against the interface  10 , when the stairlift is not in use. The footrest has spaced lateral edges  12 , a front edge  13  and a rear edge  14 , the combination of edges constituting a footrest periphery. 
     The invention is particularly concerned with the footrest  9  and thus the remainder of the chair, and its mounting on a stairlift rail (not shown), will not be described in further detail. 
     A stairlift is required, by regulation, to include some means of detecting an obstruction in the path of the stairlift, as it moves up and down the rail. Since the footrest is that part of the chair closest to the stairway, and thus an obstruction on the stairway, the requirement of the regulation is typically met by mounting a plurality of safety edges on the footrest, the safety edges being displaced in the event an obstruction is encountered, and opening one or more switches in the stairlift drive circuit to cut power to the drive motor. One arrangement of safety edges or pads is described in detail in our UK Patent No. 2 435 463, another being shown in  FIG. 4  herein. 
     As shown in  FIG. 2 , the footrest assembly comprises a main plate-like structure  15  which forms the structural basis of the footrest, and a sub-structure  16  mounted on the underside thereof, the substructure including one or more safety pads or edges  17  together with one or more cut-out switches operated upon displacement of the safety edges  17 . It will be seen that, on the lateral edges  12  of the footrest, the safety edges  17  project beyond the lateral edges  18  of the main footrest structure  15  and, upon coming into contact with an obstruction in the path of the footrest, will be displaced in the direction of arrow  19   a  in one direction, and arrow  19   b  when travelling in the opposite direction. 
     The precise form of the structure  15 , sub-structure  16  and safety edges  17  does not constitute part of the invention. What characterises the invention is the provision of flexible coverings  20  which extend along the lateral edges  12  of the footrest assembly  9  and, in so doing, cover any gaps between the safety edges  17 , and the structure  15  and sub-structure  16 . The flexible coverings  20  are sufficiently robust to withstand repeated movement of the safety edges  17  yet have sufficient flexibility not to detract from the function of the safety edges. The coverings  20  not only improve the aesthetics of the footrest assembly but also prevent the intrusion of objects and fluids into the sub-structure  16  which might interfere with the safety mechanisms incorporated into the sub-structure. 
     Referring now to  FIGS. 2 &amp; 3 , the coverings  20  are preferably included in a single component  25  that defines the periphery of the footrest assembly and thus overlies the lateral, front and rear edges of the main structure  15  but further, preferably defines the underside of the footrest and thus envelops the sub-structure  16 . 
     In the form shown the single component  25  is a moulded from a flexible natural or synthetic rubber material, one example of which is ethylene propylene diene terpolymer, more commonly referred to as EDPM. The component  25  has a top surface  26 , a bottom surface  27  and peripheral edge surface  28  which includes the flexible coverings  20 . A raised section  29  is provided along the rear edge to accommodate the hinge mounting between the footrest assembly  9  and the interface  10 . A slit  30  is provided centrally along the upper surface  26  to enable parts of the upper surface  26  to be folded back while the component is being fitted over the main structure  15  and the sub-structure  16 . 
     Referring to  FIGS. 3 &amp; 5 , in the embodiment shown the upper surface  26  of component  25  is only partly defined, leaving the central area open but including tabs or flaps  31  to enable the component  25  to be fixed about edge parts of the upper surface of main structure  15 . To this end the flaps include holes  32  to receive fasteners (not shown) for fastening the component to the main structure  15 , and also include larger apertures  33  to receive clips  35  projecting downwardly from a finishing footrest surface component, preferably in the form of tread plate  34 . The tread plate  34  is configured to overlie the tabs  31  and the open upper central section of component  25 . The tread plate can, if desired, be provided in a variety of colours and textures to meet the needs of different users. 
     Also shown in  FIGS. 3 &amp; 5  is a re-enforcement plate  36  which is fixed to the bottom surface  27  of the component  25 . To this end, the component  25  is preferably provided with a shallow cavity  37  on the underside thereof, the peripheral edge  38  defining the cavity having inwardly tapering edges to retain the plate  36  although retention of the plate can be supplemented, if necessary by the use of an adhesive between the plate  36  and the component  25 . 
     It will be appreciated that the provision of plate  36  contributes rigidity to the component  25 , particularly where the sub-structure  16  includes safety switches that are triggered in the event the foot rest bears down on an obstruction vertically below the footrest. However the plate can also contribute to the aesthetics of the stairlift as, when the stairlift is not in use and the footrest is folded up into the stowed position, the plate  36  will be exposed. Thus the plate  36  can, if desired, be provided in a variety of colours and/or textures to meet the demands of particular users.