Abstract:
An assembly for holding a spare wheel of a motor vehicle includes a cradle, a cradle support, and a holding member. The cradle accommodates a spare wheel and is mounted pivotably between a closed position and an open position. The cradle support includes a link area fixed to the underside of the vehicle and a part forming a pivot for the cradle. The holding member of the cradle support or of the cradle includes an adjustment portion extending under the link area of the cradle support or of the cradle when the motor vehicle is in the driving position.

Description:
BACKGROUND 
     The invention relates to the field of motor vehicles, and more particularly to that of devices for accommodating a spare wheel below a motor vehicle. 
     A spare wheel of a vehicle is generally retained below the floor of the vehicle by means of a support, which itself is suspended below the body or chassis of the vehicle. A support of this type can be actuated such as to release the spare wheel when the latter must be used. Supports of this type are described for example in FR 2 922 669 and FR 2 723 715. 
     Spare wheel supports which are arranged on the underface of motor vehicle bodies are subjected to difficult functioning conditions. The supports are subject for example to strong vibrations, impacts, projections, corrosive conditions, etc. Irrespective of the origin, including during the production or assembly, malfunctioning or breakage of a connection between a support of this type and the remainder of the vehicle constitutes a high risk. When incidents of this type occur below a vehicle which is travelling, the consequences for the safety of the passengers of the vehicle and other road users can be serious. 
     BRIEF SUMMARY 
     The objective of the invention is to eliminate the aforementioned disadvantages. 
     The applicant proposes an assembly for retention of a spare wheel of a motor vehicle, comprising:
         a cradle, comprising a connection area which is secured in a removable manner on the underface of the motor vehicle, said cradle being able to accommodate a spare wheel of a motor vehicle, the cradle being fitted such as to pivot between a closed position, in which the handling of a spare wheel is prevented, and an open position, in which the handling of the spare wheel is permitted;   a cradle support, comprising a connection area which is secured on the underface of the motor vehicle, and a part which forms a pivot for the cradle.       

     The assembly additionally comprises at least one unit for retention of the cradle support and/or of the cradle. The retention unit comprises a take-up portion which extends below the connection area of the cradle support or the cradle, in particular when the motor vehicle is in the travelling position. 
     The retention assembly can have the following characteristics, alone or in combination:
         the unit for retention of the cradle support and/or of the cradle is secured on the underface of the motor vehicle. In particular, the unit for retention of the cradle is secured in a removable manner, for example by being screwed, on the underface of the motor vehicle. This unit for retention of the cradle can in particular form part of a lock which is designed to lock the cradle in the closed position;   the connection area of the cradle support is secured on the underface of the motor vehicle at least partly by welding. Securing of this type is rapid to implement, and compatible with the assembly chains which exist in the motor vehicle field;   the connection area of the cradle support is secured on the underface of the motor vehicle at least partly by screwing and/or clamping. Securing of this type can easily be repaired in the event of malfunctioning;   the take-up portion of the retention unit is in the form of a hook. A hook of this type forms a stable seat for accommodation of the connection area of the cradle support;   the retention unit comprises a bent metal plate. The production of a unit of this type is rapid and inexpensive. No additional complex part is necessary;   the retention unit and the cradle support or the cradle are welded to one another. The retention unit and the cradle support or the cradle can be assembled independently from the remainder of the vehicle. Their mutual positioning is pre-established, and the risk of error during the assembly on the vehicle body is reduced;   the retention unit is made in a single piece. The presence of an assembly point which can give rise to fragility is avoided. The number of production operations is limited;   the take-up portion of the retention unit is designed to be active only when the securing of the cradle support or the cradle on the underface of the motor vehicle is defective, or when the securing of the connection area on the retention unit is defective. Before any rupture of a first mechanical connection takes place, the take-up portion is spared, and is not subjected to any significant stress. Fatigue of the part is avoided. The service life is increased;   the take-up portion of the retention unit surrounds at least partially the connection area of the cradle support or of the cradle, such that, in the event of a defect in the securing of said connection area of the cradle support or of the cradle on the underface of the motor vehicle, or in the event of a defect in the securing of said connection area on the cradle support or on the cradle, the take-up portion opposes the fall of the cradle. The cradle is retained better, in particular when the vehicle is travelling.       

    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Other characteristics, details and advantages of the invention will become apparent from reading the following detailed description and the appended drawings, in which: 
         FIG. 1  is a view in perspective of an assembly according to the invention, in which the floor of the vehicle and the spare wheel are not represented; 
         FIG. 2  is a detailed view of the assembly in  FIG. 1 , seen from a viewpoint opposite that in  FIG. 1 ; 
         FIG. 3  is a detailed view in perspective of part of an assembly according to the invention; 
         FIG. 4  is a detailed view of  FIG. 3  from a viewpoint different from that in  FIG. 3 ; 
         FIG. 5  is a detailed view in perspective of part of an assembly according to the invention; and 
         FIG. 6  is a detailed view of  FIG. 5  from viewpoint different from that in  FIG. 5 . 
     
    
    
     DETAILED DESCRIPTION 
     The following drawings and descriptions contain substantially elements of a certain nature. They can thus be used not only to make the present invention better understood, but also contribute towards its definition, if applicable. 
     Hereinafter, the terms which define relative positionings such as “top”, “bottom”, “horizontal”, “vertical” and “below” are used in a context in which the wheels of the motor vehicle are supported in a conventional manner on substantially horizontal ground. In this case, “lower surface” means surfaces which are situated on the underface of the vehicle body, and are generally oriented towards the ground. 
     Substantially parallel perpendicular or at right-angles means a direction/an angle which is spaced by at the most ±20°, or at the most 10°, or at the most 5°, from a direction which is parallel or perpendicular or from a right-angle. 
     In  FIG. 1 , a cross-member  200  belonging to the vehicle body is represented. In order to facilitate understanding, the remainder of the vehicle body is not represented. The cross-member  200  supports lower surfaces  201  on the underface of the vehicle. The assembly for retention of a spare wheel of the motor vehicle has the reference  100 . The assembly  100  comprises a cradle support  10 , a cradle  20 , two units  40   a ,  40   b  for retention of the cradle  20 , and two units  60  for retention of the cradle support  10  which are similar, and optionally a lateral position limiter  30 . The assembly  100  has a configuration which is substantially symmetrical according to a vertical plane perpendicular to the lateral direction (left-right) of the vehicle. 
     In the example described here, the cradle support  10  comprises a rigid metal wire. The metal wire is in the general form of a “W” obtained by bending of rigid metal wire. At each of the end portions of the metal wire, the cradle support  10  comprises a connection area  11 . The connection area  11  is broken down into fastener part  12  and a free end part  15 . The fastener parts  12  are secured on a lower surface  201  of the cross-member  200  of the motor vehicle, cf.  FIGS. 3 and 4 . The cradle support  10  additionally comprises two parts which form a pivot  13  in the low area of the form in the shape of a “W”. The parts which form a pivot  13  are situated in the low part of the cradle support  10  relative to the fastener parts  12  and to the free end parts  15  situated in the high part of the cradle support  10 . 
     The cradle  20  forms a receptacle for a spare wheel of a motor vehicle. In the example described here, the cradle  20  comprises a rigid metal wire. The cradle  20  is formed by bending rigid metal wire such as to provide the cradle  20  with the general form of a “U”. 
     The cradle  20  comprises a central branch  21 , and two lateral branches  23  which extend substantially perpendicularly to the central part  21 , and generally parallel relative to one another. The two lateral branches  23  are each extended, at their free end opposite the central branch  21 , by a bearing  25 . Each bearing  25  corresponds to one of the two end portions of the rigid metal wire, and is formed by bending end portions in the form of a loop. Each loop is disposed around a corresponding part which forms a pivot  13  of the cradle support  10 . The loops can be fitted, or directly formed by bending, around the pivots  13 . The pivots  13  of the cradle support  10  and the bearings  25  of the cradle  20  cooperate in order to pivot the cradle  20  relative to the cradle support  10 . The cradle  20  pivots around a geometric axis which is substantially parallel to the cross-member  200 . The cradle  20  is suspended on the cradle support  10  by means of the bearing  25 /pivot  13  assemblies. 
     The cradle  20  can be pivoted between a closed position, in which the handling of a spare wheel is prevented, and an open position, in which the handling of the spare wheel is permitted. In this case, handling of the wheel means the insertion of a spare wheel in the receptacle formed by the cradle  20 , or the extraction of a spare wheel from the receptacle formed by the cradle  20 , depending on the situations. When a spare wheel is accommodated in the cradle  20 , the spare wheel is supported on each of the lateral branches  23  of the cradle  20 . The central branch of the cradle  20  acts as a handle during the pivoting. In the open position, the central branch  21  is in the low position. In the closed position, the central branch  21  is in the high position. 
     At each of the intersections of its lateral branches  23  and its central branch  21 , the cradle  20  additionally comprises a connection area  22  comprising a fastener part  22   a  and a free part  22   b . The fastener parts  22   a  are secured in a removable manner on the underface of the motor vehicle. 
     In the example described here, the lateral position limiter  30  comprises a rigid metal wire in the form of a “U” obtained by bending of the wire. The lateral position limiter  30  comprises two short branches which extend substantially vertically from the underface of the vehicle, and the lower ends of which are extended substantially at right-angles, and are joined by a longer third branch which extends substantially according to the lateral direction of the vehicle. The third branch is disposed perpendicularly below each of the lateral branches  23  of the cradle  20 . The lateral position limiter  30  is formed such as to position the spare wheel laterally, in other words substantially parallel to a transverse direction of the vehicle, and thus prevent any interference between the spare wheel and the underpart of the vehicle body during handling of the cradle  20 . The bent ends of the short branches form a non-aggressive area for the operator in the factory. 
     The cradle support  10 , the cradle  20  and the lateral position limiter  30  are is case produced by bending a similar metal wire. In variants, different metal wires can be used for the cradle support  10 , the cradle  20  and the lateral position limiter  30 . Production by bending makes it possible to avoid the creation of fragile connections such as welding spots. The different parts can be produced from other materials, for example plastic materials and/or in the form of tubes, formed bars, or even flexible wires. As a variant, the cradle support  10 , the cradle  20  and/or the lateral position limiter  30  can be produced by assembling a plurality of parts. In addition, certain parts can be covered with a covering in order to improve the resistance to corrosion and/or avoid noises of the rattling type derived from the vibrations of the vehicle. Units which facilitate the pivoting, such as rings or roller bearings, can be provided between the bearings  25  and the pivots  13 . 
     Reference now made to  FIGS. 3 and 4 . In this case, the retention unit  60  is produced by bending a metal sheet or plate. As a variant, the retention unit  60  can be made by molding, drawing and/or machining. The retention unit  60  comprises a securing portion  61  and a take-up portion  63  or lug. 
     The securing portion  61  has a substantially flat form. The securing portion  61  is provided with two through holes, one of which receives a screw  72 . In this case, the securing portion  61  is in contact with a lower surface  201  of the vehicle. The lower surface  201  of the vehicle is in this case supported by the cross-member  200 . The securing portion  61  is retained against the lower surface  201  by the screw  72 . The screw  72  is engaged in the cross-member  200  and in a corresponding nut (not shown in the figures). The nut is supported against the cross-member  200 . As a variant, the nut can be integral with the cross-member  200 , for example it can be welded on it. The securing of the retention unit  60  on the underface of the vehicle by means of a removable fastener, such as a screw-nut pair, makes it possible to dismantle the retention unit  60  and the assembly  100  from the remainder of the vehicle if necessary. As a variant, the retention unit  60  can be secured definitively on the remainder of the vehicle, for example by means of welding or adhesion. 
     The fastener part  12  of the connection area  11  is oriented substantially parallel to the cross-member  200 . The fastener part  12  of the connection area  11  is oriented substantially according to a lateral direction of the vehicle. The free end part  15  extends the fastener part  12  substantially at right-angles. The free end part  15  extends substantially according to a direction perpendicular to the cross-member  200 . The free end part  15  extends substantially according to a longitudinal direction (from front to rear) of the vehicle. The substantially right-angle between the fastener part  12  and the free end part  15  of the connection area  11  is obtained by bending metal wire when the cradle support  10  is formed. 
     The fastener part  12  is secured on the underface of the vehicle. In the example described here, this securing is indirect: the fastener part  12  is secured by welding against the retention unit  60 . The retention unit  60  is secured on a lower surface  201  of the cross-member  200 . This indirect securing facilitates the assembly: the securing between the cradle support  10  and the retention unit  60  can be carried out before the installation below the vehicle body, then, in a second stage, the retention unit  60  which is integral with the cradle support  10  can be secured on the body of the vehicle. As a variant, the cradle support  10  is secured directly on the underface of the vehicle, for example directly against the lower surface  201  of the cross-member  200 . 
     The fastener part  12  is rendered integral with the cross-member  200 , and thus with the vehicle body. In this case, this securing is obtained by welding of the fastener part  12  on a surface which is oriented downwards of the securing portion  61  of the retention unit  60 . A welding bead bears the reference  70  in the figures. This securing constitutes a mechanical connection between the cradle support  20  and the body or chassis of the vehicle. 
     In variants, the mechanical connection can be obtained by means other than welding, for example adhesion, drawing, riveting, screwing and/or any other means which are appropriate according to the technical constraints. 
     The take-up portion  63  supplements the mechanical connection between the fastener part  12  and the lower surface  201 , in order to prevent an abnormality in the mechanical connection. In this case, take-up portion  63  means a portion which serves the purpose of taking up, i.e. preventing the fall of, the cradle support  10  in an incident situation in which a fastener of the cradle support  10  on the underface of the vehicle fails. The take-up portion  63  then acts as a mechanical standby for the securing between the fastener part  12  and the lower surface  201 . 
     In this case, the take-up portion  63  in the form of a hook. The take-up portion  63  forms a projection downwards relative to the plane of the securing portion  61 . The take-up portion  63  has a concave surface which is oriented upwards. The concave surface forms a seat for receipt of the free end part  15  of the cradle support  10 . The form and dimensions of the take-up portion  63  are adapted according to the form and dimensions of the connection area  11 , and in particular the free end part  15  of the cradle support  10  which it accommodates in the installed state. The take-up portion  63  extends below the connection area  11  and in particular below the free end part  15  of the cradle support  10 . In the example described here, the inner space defined by the take-up portion  63  has a generally elongate form perpendicularly to the cross-member  200 , i.e. substantially according to a longitudinal direction of the vehicle. The inner space forms a groove. The groove has a substantially constant cross-section according to the longitudinal direction. The cross-section of the groove is substantially rounded with a diameter which is larger than, or equal to, the diameter of the metal wire which constitutes the free end part  15  of the connection area  11  of the cradle support  10 . 
     The free end part  15  of the connection area  11  of the cradle support  10 , in the installed state, is accommodated above the take-up portion  63 , in this case in the rounded groove. For as long as the mechanical connection between the fastener part  12  and the lower surface  201  of the vehicle is effective, i.e. the connection between the fastener part  12  and the retention unit  60  in the present example, the take-up portion  63  is inactive. The free end part  15  can be in contact with, or slightly spaced above, the take-up portion  63 . The cradle support  10  is supported by means of the mechanical connection, in this case the welding bead  70  and the fastener part  12 , which is thus subjected to traction. In the case of a defect of this mechanical connection, for example rupture of the welding bead  70 , the fastener part  12  drops and the free end part  15  is taken up by the take-up portion  63 . 
     Complete falling of the cradle support  10  is prevented. The free end part  15  is then supported on the take-up portion  63 . In other words, the fastener part  12  of the connection area  11  forms a first mechanical connection in normal functioning, and the free end part  15  of the connection area  11  forms a second, standby mechanical connection, in the case of malfunctioning of the first mechanical connection. 
     A free end  63   a  of the take-up portion  63  is curved upwards. In the example described here, the free end  63   a  is curved upwards substantially as far as the plane of the securing portion  61 . In the state in which it is secured against the lower surface  201  of the cross-member  200 , the free end  63   a  of the take-up portion  63  comes into contact with, or is spaced slightly apart from, the lower surface  201 . In other words, the take-up portion  63  extends below the free end part  15  of the connection area  11  and surrounds it partially. Thus, falling of the free end part  15  from the receptacle formed in the take-up portion  63  by translation and/or sliding in a substantially lateral direction is prevented. The free end  63   a  of the take-up portion  63  acts as an anti-fall rim. As a variant, the take-up portion  63  is arranged below the connection area  11 . The groove surrounds the free end part  15  around 90° to 180° of the cross-section. 
     Reference is now made to  FIGS. 5 and 6 . The retention assembly  100  additionally comprises at least one unit for retention of the cradle  20  arranged on the cradle  20  side opposite the pivots  13 . In order to facilitate access to the spare wheel by a user, the central branch  21  which acts as a handle and the units for retention of the cradle  20  are situated in the vicinity of the rear end of the vehicle. 
     In the example represented, the assembly  100  comprises a left-hand retention unit  40   a  for the cradle  20  and a right-hand retention unit  40   b  for the cradle  20 . The retention units  40   a ,  40   b  are secured in a removable manner on the underface of the motor vehicle. Two angle irons  203  which are integral with the vehicle body are represented in the figures. The faces which are oriented downwards of the angle irons in this case constitute lower surfaces  205  which belong to the underface of the vehicle. 
     The retention units  40   a  and  40   b  are similar to the retention unit  60  for the cradle support  10  described with reference to  FIGS. 3 and 4 . In this case, each retention unit  40   a ,  40   b  is produced by bending a metal sheet or plate. As a variant, the retention unit  40   a ,  40   b  can be produced by molding, drawing and/or machining. 
     Each retention unit  40   a ,  40   b  comprises a securing portion  41   a ,  41   b  respectively, and a take-up portion  43   a ,  43   b  respectively, or lug. 
     Each securing portion  41   b  has a substantially flat form. The securing portion  41   a  of the left-hand retention unit  40   a  is provided with a through opening  44 . The securing portion  41   b  of the right-hand retention unit  40   b  is also provided with a through hole  47  which receives a screw (not represented in the figures). The securing portions  41   a ,  41   b  are secured on a lower surface  205  of the motor vehicle. The left-hand securing portion  41   a  is secured by means of the screw  45 . The screw  45  passes through the left-hand securing portion  41   a  and engages in a nut  46  which is supported by the angle iron  203 . The right-hand securing portion  41   b  is secured by another screw, not represented, on the lower surface  205  of the angle iron  203 . 
     The securing between the securing portions  41   a ,  41   b  and the lower surface  25  of the vehicle is removable. By means of complete unscrewing of the screws on the right-hand and left-hand sides, the left-hand  41   a  and right-hand  41   b  securing portions can be separated from the angle irons  203 . The cradle  20  can then be pivoted towards its opening position. 
     In the embodiment represented in the figures, complete unscrewing of the left-hand screw  45  is superfluous. Loosening the screw  45  is sufficient to permit manual sliding of the securing portion  41   a  relative to the lower surface  205 . Sliding of this type of the securing portion  41   a  (towards the left in  FIG. 5 ) and resilient deformation of the cradle  20  are sufficient to align the screw  45  and the opening  44  in the securing portion  41   a . The opening  44  has a size larger than the head of the screw  45 . Thus, the securing portion  41  can be withdrawn downwards, by making the screw head  45  pass through the opening  44 . The screw  45  continues to be engaged in the corresponding nut, integrally with the angle iron  203 . Falling onto the ground and loss of the screw  45  are avoided. In a variant, the screw  45  is designed to make impossible complete unscrewing and removal of the screw  45 . The differences between the openings  46 ,  47  in the two securing portions  41   a  and  41   b  form an exception to the symmetrical nature of the assembly  100 . 
     As previously stated, the connection areas  22  of the cradle  20  are secured in a removable manner on the underface of the motor vehicle. In the example described here, this securing is indirect, which makes it possible to facilitate the assembly, as already stated for the retention unit  60 . The fastener part  22   a  is secured by welding against the left-hand retention unit  40   a , which itself is secured in a removable manner on a lower surface  205  of the vehicle, as already described. In this case, the fastener part  22   a  is secured on a surface which is oriented downwards of the plate  41   a  of the left-hand retention unit  40   a  by means of a welding bead  50  ( FIG. 5 ). This securing constitutes a mechanical connection between the cradle  20  and the body or chassis of the vehicle. The securing of the fastener part  22   a  on the securing portion  41   b  of the right-hand retention unit  40   b  is similar. In variants, the mechanical connection can be obtained by other means, for example by gluing, drawing, screwing and/or any other appropriate means. 
     Each retention unit  40   a ,  40   b  of the cradle  20  has a take-up portion  43   a ,  43   b  respectively, similar to the take-up portion  63  of the connection unit  60 , which acts as a supplement to the mechanical connection between the fastener part  22   a  and the lower surface  205 , in order to prevent an abnormality of the mechanical connection. Thus, the take-up portions  43   a ,  43   b  also serve the purpose of preventing falling of the cradle in a situation in which securing of the cradle on the underface of the vehicle fails. 
     In the present example, the take-up portions  43   a ,  43   b , which are identical to the take-up portion  63 , extend below the connection area  22 , and have a concave surface which is oriented upwards and receives the free part  22   b  of the connection area  22  of the cradle  20 . In the example described here, the inner space defined by the take-up portion  43   a ,  43   b  has an elongate form, and also extends substantially according to a longitudinal direction of the vehicle. However, the invention is not limited to this orientation. The dimensions of the groove formed by the inner space are similar to those of the take-up part  63  of the retention unit  60 . 
     Thus, the free part  22   b  of the connection area  22  of the cradle, the installed state, is accommodated above the take-up portion  43   a ,  43   b . For as long as the mechanical connection between the fastener part  22   a  and the lower surface  205  is effective, i.e. in this case the connection between the fastener part  22   a  and the retention unit  43   a ,  43   b , the take-up portion  43   a ,  43   b  is inactive. The free part  22   b  can be in contact with, or slightly spaced above, the take-up portion  43   a ,  43   b . The cradle  20  is supported by means of the mechanical connection, in this case the welding bead  50  and the fastener part  22   a , which is subjected to traction. In the event of failure of this mechanical connection, for example rupture of the welding bead  50 , the fastener part  22   a  falls, and the free part  22   b  is taken up by the take-up portion  43   a ,  43   b , thus preventing complete falling of the cradle  20 . 
     The take-up portion  43   a ,  43   b  can also have a free end which is formed such as to act as an anti-fall rim, like the take-up portion  63  of the retention unit  60 . 
     The securing portions  41   a ,  41   b  and the take-up portions  43   a ,  43   b  respectively of the retention units  40   a ,  40   b  described here have similarities of form with the securing portions  61  and the take-up portions  63  of the retention units  60 . This makes it possible to facilitate the production of the parts, for example by using the same basic materials, such as metal plates, from which the parts are cut out and pierced before being bent. The retention units  40   a ,  40   b  and  60  have the common purpose of supporting the weight of the cradle support  10 , the cradle  20  and the spare wheel which is accommodated in it. However, the retention units  40   a ,  40   b  can be operated by a user in order to release the cradle  20 , whereas the retention units  60  serve the purpose of retaining the cradle support  10  in all from circumstances (apart dismantling for maintenance or repair). 
     In this case, the retention units  40   a ,  40   b  of the cradle  20  thus form a lock which is designed to lock the cradle  20  in the closed position. 
     Thanks to the mechanical standby provided by the take-up portion  63 ,  43   a ,  43   b , the vehicle can continue to travel, since the cradle  20  is retained, even in the case of failure of the mechanical connection between the fastener part  12  and the lower surface  201  and/or between the fastener part  22   a  and the lower surface  205 . A major risk for safety, an immediate immobilization of the vehicle, and urgent repair, are avoided. 
     The invention is not limited to the assemblies described above purely by way of example, but incorporates all the variants which persons skilled in the art could envisage within the context of the following claims.