Patent Publication Number: US-2005133550-A1

Title: Supporting unit for an external spare wheel

Description:
The present invention relates to a supporting unit for an external spare wheel.  
      In general, as is illustrated schematically in the figure designated by “Prior Art”, supporting units of a known type are designed for supporting a spare wheel  2  underneath the floor panel  3  of a motor vehicle and comprise: 
          a box-section bracket anchored to the floor panel;     a bell  5 , which can be fitted to the spare wheel  2  and can be moved with respect to the bracket  4  away from and towards a recovery position, in which the bell  5  is set up against the bracket  4 ;     a cable  6  for transmitting motion, which passes through the bracket  4  and has one end  7  anchored to the bell  5 ; and     a clamping device  8  set between the bracket  4  and the bell  5  for blocking the bell  5  in its recovery position.        

      The fact that the supporting units of the type described above are set in a position in which they are exposed to atmospheric agents renders them particularly subject to malfunctioning and sticking of the bell above all when the spare wheel, the weight of which ensures a proper descent of the bell, is not present.  
      The purpose of the present invention is to provide a supporting unit for an external spare wheel which will be more resistant to atmospheric agents and will enable, at the same time, any sticking of the bell to be prevented.  
      According to the present invention, a supporting unit for an external spare wheel is provided, designed to support the spare wheel underneath the floor panel of a motor vehicle, said supporting unit comprising: 
          a box-section bracket anchored to the floor panel;     a bell, which can be fitted to the spare wheel and can be moved with respect to the bracket away from and towards a recovery position, in which the bell is set up against the bracket;     a cable for transmitting motion, which passes through the bracket and has one end anchored to the bell; and     clamping means set between the bracket and the bell for blocking the bell in its recovery position.        

      The supporting unit is characterized in that it comprises anti-sticking means associated to the box-section bracket, said means in turn comprising an elastic compression element set between the bell and the supporting bracket that can be activated upon de-activation of the clamping device, and a seal element associated to the bell for co-operating with the box-section bracket. 
    
    
      The invention will now be described with reference to the annexed drawings, which illustrate a non-limiting example of embodiment thereof, and in which:  
       FIG. 1  is a perspective view of a first preferred embodiment of the supporting unit for a spare wheel made according to the present invention;  
       FIG. 2  is a perspective view, with parts removed for reasons of clarity, of the supporting unit of  FIG. 1 ;  
       FIG. 3  is a side elevation of a second embodiment of the supporting unit for a spare wheel of  FIG. 1 ;  
       FIG. 4  is a perspective view of a third embodiment of the supporting unit for a spare wheel of  FIG. 1 ;  
       FIG. 5  is a side elevation, with parts represented in cross-sectional view and parts removed for reasons of clarity, of the supporting unit of  FIG. 4 ; and  
       FIG. 6  is a side elevation of a fourth preferred embodiment of the supporting unit for a spare wheel of  FIG. 1 . 
    
    
      With reference to  FIGS. 1 and 2 , and using the same reference numbers as the ones used for designating parts that are the same or similar already described in the introductory part of the description, the reference number  1  designates, as a whole, a supporting unit for an external spare wheel  2 .  
      The unit  1  is designed for supporting the spare wheel  2  underneath the floor panel  3  of a motor vehicle, and comprises: 
          a box-section bracket  4  anchored to the floor panel  3 ;     a bell  5 , which can be fitted to the spare wheel  2  and can be moved with respect to the bracket  4  away from and towards a recovery position, in which the bell  5  is set up against the bracket  4  to clamp the wheel  2  up against the floor panel  3 ;     a cable  6  for transmitting motion, which passes through the bracket  4  and has one end  7  fixed to the bell  5 ; and     a clamping device  8  set between the bracket  4  and the bell  5  for blocking the bell  5  in its recovery position.        

      The box-section bracket  4  comprises a substantially parallelepipedal anchoring base  11  and a vertical tubular body  12 , which is set transverse to the base  11  and extends from the base  11  on the opposite side of the floor panel  3  with respect to the base  11 . In particular, the base  11  is defined by two cup-like half-shells  13  assembled together and has a front hole  14  and a coupling socket  15 , which is fixed to a bottom wall  16  of the base  11  itself and has, through one bottom wall  17  thereof a respective through hole  18  for setting the base  11  in communication with the body  12 .  
      The body  12  is coupled on the socket  15  so that it extends along a vertical axis A from the wall  16  and has a bottom mouth portion  20  having a substantially conical shape flared out downwards. The body  12  is moreover provided with a through slit  21 , which is transverse to the axis A and is made through the body  12  itself at a certain distance from the mouth portion  20 .  
      The cable  6  for transmitting motion is inserted inside the base  11  through the hole  14  and comes out from the base  11  through the hole  18  to extend along the axis A within the body  12 .  
      The clamping device  8  comprises a snap-action arm  23  hinged on the outside of the bracket  4  in a position corresponding to the base  11  on the opposite side of the hole  14 , a further cable  24  for transmitting motion connected to the arm  23  for moving the arm  23  itself away from and towards the clamping position, and an actuating lever  25 , which is hinged to the tubular body  12  and is set between the cable  24  and the arm  23  for actuating the arm  23  itself.  
      The arm  23  is a flexible elastic arm that is designed to bend with respect to a fulcrum element  26  connected to the base  11  and is provided with a coupling end  27 , which is set inside the body  12  through the slit  21  and is kept inside the body  12  thanks to the flexibility of the arm  23  itself.  
      The lever  25  is a first-class lever and is bracketed in a rotatable way on the body  12  with an action arm  28 , which extends in the direction of the base  11  and is coupled to the cable  24 , and with a resistant arm  29 , which extends in the direction of the mouth portion  20  and is engaged with the arm  23 .  
      Finally, the clamping device  8  comprises a shaped bushing  30 , which is fixed to the end  7  of the cable  6  and is set between the cable  6  and the bell  5 . The bushing  30  is arranged in a slidable way inside the tubular body  12  and has a plurality of annular projections  31 , which are arranged in series with respect to the axis A and are designed to be intercepted by the coupling end  27 . Each projection  31  is delimited at the top by a respective conical surface  32  and is delimited at the bottom by a respective flat surface  33  transverse to the axis A so as to enable the end  27  to slide on the projection  31  during insertion of the bushing  30  into the body  12  and to be inserted between one projection  31  and the other, so clamping the bushing  30  itself axially.  
      The unit  1  further comprises an anti-sticking device  40 , which is associated to the bracket  4  to prevent any sort of sticking whether of the bell  5  or of the cable  6  due to causes extraneous to the unit itself, such as, for example, infiltration of debris inside the bracket  4  itself, and in order to guarantee movement of the bell  5  away from its own recovery position even in the case where the wheel  2  is not present.  
      The device  40  comprises a helical spring  41 , which is set along the axis A and is designed to be compressed between the bushing  30  and the wall  17  of the socket  15  in order to exert an elastic action of thrust on the bushing  20  itself. The device  40  further comprises two seal elements  42  and  43 , which are designed to isolate the bracket  4  from the outside world by means of a sealing action and of which the element  42  is associated to the bell  5 , whilst the element  43  is associated to the base  11 .  
      In particular, the element  42  is defined by a shaped bushing, which is set between the bell  5  and the bushing  30  and has two annular projections  44  shaped like a truncated cone, as well as a hemispherical body  45 , which are designed to interact with the mouth portion  20  so as to seal the body  12  with the bell  5  set in its recovery position.  
      The element  43 , instead, is set for closing the hole  14  and comprises a cylindrical plug  46  made of a rubbery material, and a flexible guide  47  again made of rubbery material, which is fixed to the plug  46 . Both the plug  46  and the guide  47  are traversed by the cable  6  and, whilst the guide  47  extends inside the base  11  from the plug  46  up to the hole  18 , the plug  46  also functions as clamping terminal for a sheath  6 ′ of the cable  6 .  
      In use, the unit  1  enables both clamping and support of the wheel  2  underneath the floor panel  3 , as well as release of the wheel  2  itself.  
      In order to enable movement of the cable  6  through the bracket  4 , it is initially necessary to release the bushing  30 . Consequently, it is necessary to act on the cable  24  in order to bend the arm  23  and disengage the end  27  from the projections  37 . At this point, the cable  6  is free, and it is possible to carry out descent of the bell  5  either as a result of the action of the weight of the wheel  2  or, in the absence of the wheel  2 , as a result of the elastic action of expansion of the spring  41  in so far as the weight of the bell  5  might not be sufficient either to overcome the sealing action of the element  42  on the mouth portion  20  or to overcome the initial resistance due to the friction between the components or else to possible debris that has accumulated on the outside the mouth portion  20 .  
      Instead, after the bell  5  has possibly been inserted through the wheel  2  and the cable  6  has been recovered by means of a recovering device (not illustrated) set on board the vehicle, the wheel  2  is drawn into the proximity of the vertical axis of the unit  1  and is also raised until the seal element  42  is completely inserted inside the tubular body  12  through the mouth portion  20  and the coupling end  27  is inserted between two projections  31 .  
      From the foregoing description, it is clear that the anti-sticking device  40  prevents both entry of debris inside the box-section bracket  4 , so enabling the cable  6  to be moved through an environment that is substantially free from obstacles, and dropping as a result of gravity of the bell  5 , notwithstanding the axis of the wheel  2 , the weight of which practically enables on every occasion to bring down the bell  5  from the recovery position.  
      In effect, the position of the unit  1  underneath the floor panel  3  not only exposes the unit  1  to every sort of contaminating agent but it also prevents regular maintenance thereof. As a result, in the absence of the device  40 , encrustations are formed inside the unit  1  such as to prevent proper moving of the cable  6 . In addition, said encrustations render practically impossible descent of the bell  5  in the absence of the wheel  2 , and consequently it is readily understandable how the greater internal cleanliness of the box-section bracket  4  and the elastic action of expansion of the spring  41 , once the end  27  has been disengaged from the projections  31 , always guarantee descent of the bell  5 .  
      The embodiment illustrated in  FIG. 3  relates to a unit  50  similar to the unit  1 , from which the unit  50  differs in that the base  11  and the body  12  are integrated together in an elongated body  51 , which is altogether similar to the body  12 , extends along the axis A, and is formed by two shells  52  connected together. In particular, the two shells  52  have respective peripheral edges  53  connected to one another with the aid of a plurality of rivets  54 .  
      The unit  50  moreover differs from the unit  1  in that the arm  23  is directly connected to the cable  24 , and the lever  25  is consequently not present. Furthermore, the coupling end  27  is mobile also inside a through slot  55  made through two edges  53 .  
      Operation of the unit  50  is similar to that of the unit  1  and consequently does not call for any further explanation.  
      The embodiment illustrated in  FIGS. 4 and 5  relates to a unit  60  similar to the unit  1 , from which the unit  60  differs, in the first place, in that it is not provided with the arm  32  and, in the second place, in that the clamping device  8  comprises a sleeve  61 , which is set outside the tubular body  12  around the slit  21  and comprises a radial tooth  62  set through the slit  21  itself and in contact with the bushing  30 .  
      The sleeve  61  further comprises a elastic supporting portion  63 , which is connected outwards to the arm  29  of the lever  25  and inwards to the tooth  62  in order to enable movement of the tooth  62  away from and towards the projections  31  of the bushing  30 .  
      The device  40  of the unit  60  further comprises, in addition to the lid  45 , also a further conical disk  64  made of rubbery material, which is mounted on the opposite side of the lid  45  with respect to the bell  5  and has an outer diameter larger than that of the mouth portion  20  so as to exclude further any possibility of entry of debris into the body  12 . The conical disk  64  may advantageously be applied also to the bell  5  of the unit  1 .  
      Also operation of the unit  60  is similar to that of the unit  1  and consequently does not call for any further explanation.  
      The embodiment illustrated in  FIG. 6  relates to a unit  70  similar to the unit  1 , from which the unit  70  differs, in the first place, in that the base  11  and the body  12  are integrated together in an elongated body  71 , which is altogether similar to the body  12 , and extends along the axis A. In addition, the arm  23  is not only hinged on the body  71  and directly connected to the cable  24  but is also set inside the body  71  itself.  
      Consequently, the body  71  is provided not only with the hole  14  for passage of the cable  6  and with the plug  46  set so as to provide hermetic closing of the hole  14  itself but also with a further hole  74  and a further plug  7 . 6 , which are axially arranged so that they are aligned with the hole  14  and the plug  16  themselves.  
      Also operation of the unit  70  is similar to that of the unit  1  and consequently does not call for any further explanation.  
      It is understood that the invention is not limited to the embodiments described and illustrated herein, which are to be considered merely as examples of embodiment of the supporting unit, it being instead possible for said supporting unit to undergo further modifications regarding shapes and arrangement of parts, and constructional and assembly details.