Abstract:
A static temporary storage device for motor vehicle body parts, the device has a stationary frame; at least two stationary parallel rails that are mounted horizontally or in a slightly angled manner on the frame each rail being capable of supporting a bearing fitted onto the rail so as to be longitudinally movable on the rail; at least one carriage having bearing fitted onto the rail, the carriage being dimensioned so as to rest on both rails by means of the support; A device or means for suspending a body part from the carriage; each carriage extending longitudinally relative to the rails over a length that is shorter than the longitudinal extent of a body part when in its suspended position.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application is the U.S. National Phase application of PCT/FR2010/051453 filed Jul. 9, 2010, which claims priority to French Application No. 0954844 filed Jul. 10, 2009, which applications are incorporated herein by reference and made a part hereof. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The present invention relates to a static temporary storage device for motor vehicle body parts. 
         [0004]    2. Description of the Related Art 
         [0005]    In the present description, the term “body part” means a part made of plastics material or of metal that belongs to the visible outer shell of a motor vehicle. A body part may comprise a single piece, or it may be constituted by an assembly of a plurality of pieces, and it may be bare or it may be fitted with components. 
         [0006]    In particular, the term “bumper skin” is used to mean a body part forming a front or rear shield for a motor vehicle, the shield being made up of a single piece of plastics material or of metal or of an assembly of such pieces, and the term is used regardless of the fabrication stage of the part, i.e. regardless of whether the body part is partially or completely finished. 
         [0007]    Document FR 2 895 375 A1 discloses a device for storing bumper skins, which device enables the bumper skins to be transported while protecting them effectively against scratching or marking. 
         [0008]    The bumper skins are packaged in protective covers that are suspended individually from a rack having horizontal rails, each rack being slidable along the rails to enable the bumper skins to be loaded and unloaded on and off the storage device. The storage device is designed to be loaded on a transport vehicle to convey bumper skins according to a conventional logistics system. In the cited prior art, the protective covers serve not only to protect the bumper skins, but also to enable a larger number of bumper skins to be loaded in each storage device. 
         [0009]    The present invention relates to a static temporary storage device for motor vehicle body parts. Such a device is useful on the manufacturing site of parts in order to complete an intermediate or final treatment method, e.g. in order to allow the parts to cool or to allow a coating to harden, and/or to store them while waiting to be sent to a mounting site on a vehicle. 
         [0010]    Static temporary storage devices for bumper skins are in particular: 
         [0011]    stationary shelves, the bumper skins being placed in the position they are to occupy on a vehicle in specially storage conditions; or 
         [0012]    sheets suspended from stationary racks; or 
         [0013]    stationary horizontal bars on which the bumper skins are placed with their overriders pointing downwards. 
         [0014]    In those known devices, the bumper skins are stored so as to best protect them, but at a storage density that is not optimized. In addition, handling of the devices in order to transport them to a mounting site constitutes an operation that is relatively burdensome, possibly requiring the use of power-lift trucks (also known as fork-lift trucks). 
       SUMMARY OF THE INVENTION 
       [0015]    The present invention seeks to provide a static temporary storage device with facilitated loading and unloading, and providing loading density that can be increased without running the risk of damaging the bumper skins. 
         [0016]    Accordingly, the invention provides a static temporary storage device for motor vehicle body parts, wherein the device comprises: 
         [0017]    at least two stationary parallel rails that are mounted horizontally or in a slightly angled manner on the frame, each rail being capable of supporting a bearing fitted onto the rail so as to be longitudinally movable on the rail; 
         [0018]    at least one carriage having bearings fitted onto the rail, the carriage being dimensioned so as to rest on both rails by means of the bearings; and 
         [0019]    means for suspending a body part from the carriage; each carriage extending, longitudinally relative to the rails over a length that is shorter than the longitudinal extent of a body part, in a suspended position thereof, and preferably less than the nesting pitch of the body parts if they are capable of being nested one inside the other. 
         [0020]    In an embodiment that is adapted to bumper skins, the longitudinal dimension (relative to the rails) of the carriages is thus preferably less than 25 centimeters (cm) or approximately 9.84 inches. 
         [0021]    The device may also include protective covers, each containing a body part. 
         [0022]    By way of example, the suspension means may be constituted by straps forming loops that pass under the body parts, or by the covers only. 
         [0023]    The suspension means and possibly the covers are shaped in such a manner that the extent of two adjacent body parts is less than twice the extent of a single body part. 
         [0024]    In the context of temporary storage, suspending the body parts from carriages makes it possible firstly to increase the loading density, thereby providing an economic advantage since the storage space occupied on the manufacturing site of the body parts is smaller, and secondly to avoid certain kinds of handling that would otherwise be necessary in order to manage bulky temporary stock. 
         [0025]    In a particular embodiment of the invention, the device includes at least one separator suitable for placing between two body parts carried by two adjacent carriages, so as to prevent the body parts from being damaged if they approach each other. 
         [0026]    An advantage of separators is that the body parts can be placed tightly one against another without damage when the carriages that support the body parts are juxtaposed. The function of the separators may be performed either by providing spacing or by providing protection, however in either event the separators should encourage fitting of the body parts tightly together so as to increase the loading density of the temporary storage device of the invention. 
         [0027]    A separator according to the invention is constituted by two extra thicknesses formed on the suspension straps, which extra thicknesses bear against one another so as to form spacers between two body parts. Thus, the straps act both as suspension means and as separators. 
         [0028]    Another separator according to the invention is constituted by a curtain of flexible and damping material, such as a thick fabric, the curtain being suspended from a carriage in front of or behind the body part supported thereby, so as to protect it if it is moved close to an adjacent body part. 
         [0029]    Another separator according to the invention is constituted by a protective cover that acts both as suspension means and as a separator. 
         [0030]    A protective cover may also be used together with suspension straps. 
         [0031]    Having recourse to suspended covers provides the advantage that the body parts are protected during their temporary storage without requiring repackaging after transport, since they can be transported beforehand in the same cover. They may be transferred on a set of movable racks in a truck from a first site to a second site having a static temporary storage device according to the invention. Advantageously, it is possible for this purpose to make use of movable racks that are arranged to be capable of receiving the same carriages as those of the static storage device according to the invention, or at least the same covers. 
         [0032]    Such a cover may cover, in particular completely, the body part on a single one of its faces. Thus, since a body part is generally rounded in shape, the cover preferably covers the concave face of the part and preferably leaves its convex face uncovered, thereby enabling the body parts to be nested one in another. Furthermore, the convex face of the body part, which is generally its visible face, is protected from the impacts that might occur while the parts are being handled. This embodiment also reduces the space occupied by the adjacent parts, since only one thickness of cover is present between two body parts. 
         [0033]    A cover may also have an elastic border allowing it to fit around the shape of the body part. Such a cover is very simple to put into place on the body part. 
         [0034]    In its bottom portion, the cover may also include fasteners enabling another, identical cover to be fastened thereto. It is then possible to suspend a plurality of covers one below another from a single carriage, thereby forming a “bunch” of covers. 
         [0035]    As a result, if it is necessary to transfer the carriages from a movable rack to a static storage device, the transfer operations are reduced, thereby achieving a non-negligible saving in time. 
         [0036]    According to an advantageous embodiment of the invention, the rails are slightly angled so that the weight of each carriage, or in a variant the combined weight of each carriage together with at least one body part and the suspension means, suffices to cause the carriage to move along the rails under the effect of its own weight or, in a variant, under the effect of the combined weight of these three elements. Thus, the carriages naturally collect together at the lowest point of the rails, without consuming any energy. The movement of the carriages along the rails may give rise to jolting or even impacts between the carriages, so the fact that the body parts are suspended from the carriages constitutes an advantage of the combination of means constituting the invention. In particular, adjacent body parts carried by adjacent carriages may perform movements as a whole and thus avoid striking one another or any of them striking the walls of their own containers. 
         [0037]    In a particular embodiment of the invention, each track has a smooth top face and the respective bearings fitted onto the rails have at least one skid or at least one wheel capable of moving on the smooth top face of a rail. 
         [0038]    In another embodiment, the top face of the rail is constituted by juxtaposed wheels arranged side by side with their axes horizontal and perpendicular to the longitudinal direction of the rail, and the carriage bearings fitted onto the rails are merely legs with longitudinally smooth bottom faces that run along the wheels of the rail. In both of these embodiments, the wheels may be replaced by balls, or disks, or rollers. 
         [0039]    In another embodiment, each rail presents a longitudinally smooth top face and each carriage bearing is a skid that slides on the top face of the rail. Under such circumstances, anti-friction material, e.g. of the fluorinated polymer type, may coat the top face of the rail or the bottom face of the skid. 
         [0040]    In a particular embodiment of the invention, the bearings are guided along the rails by lips arranged at the margins of the top faces of each of the rails. Each lip projects towards the bearing and forms an abutment that prevents the bearing from leaving the rail while it is moving longitudinally, at least from leaving the rail in a direction perpendicular thereto. 
         [0041]    Two different arrangements may then be envisaged for the lips: 
         [0042]    “inside the rails” where the lips are on the side of each rail that is closest to the other rail; or 
         [0043]    “outside the rails” where the lips are on the side of each rail that is furthest from the other rail. 
         [0044]    In addition, the abutments may be vertical or sloping. They are preferably rigid. When vertical they serve to retain the bearings on the rail. When sloping, they allow each bearing to overhang from the rail by rising a little up the abutment in the event of the carriage shifting or turning relative to the rails (a small amount of pivoting about a vertical axis, also referred to as “crabbing”). This risk of pivoting is particularly great when the dimensions of a carriage are designed to increase loading density and are therefore not favorable to keeping the carriage on the axis of the rails, i.e. when the ratio of its wheel base (about 2 meters (m)) to its longitudinal width (about 15 cm to 40 cm) encourages crabbing. When the abutments are sloping, a bearing that moves up an abutment generates a force tending to recenter the bearing, thus making it possible to return the carriage back onto the axis of the rails, assuming that the angles are suitably determined given the weights and the dimensions of the various elements in question. With vertical abutments, in the event of the carriage shifting or turning, there is a risk on the contrary that the carriage will become jammed between the abutments. 
         [0045]    In an embodiment in which the abutments are placed inside the rails, the inventors have nevertheless observed, in unexplained manner, that instances of carriages jamming are considerably reduced if the abutments are vertical, and instances of carriages pivoting are likewise considerably reduced if the abutments are sloping. 
         [0046]    These and other objects and advantages of the invention will be apparent from the following description, the accompanying drawings and the appended claims. 
     
    
     
       BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS 
         [0047]    In order to better understand the invention, there follows a description of embodiments given as examples that do not limit the scope of the invention, the description being given with reference to the accompanying drawings, in which: 
           [0048]      FIG. 1  is a diagrammatic view in elevation of a temporary storage device according to an embodiment; 
           [0049]      FIG. 2  is a perspective view of a carriage mounted on rails and carrying a bumper skin, according to a first embodiment; 
           [0050]      FIG. 3  is a section view on plane III-III of  FIG. 2  showing a carriage according to a second embodiment; 
           [0051]      FIG. 4  is a view analogous to  FIG. 3 , the rails being made according to a second embodiment; 
           [0052]      FIG. 5  is a view analogous to  FIGS. 3 and 4 , the rails being made according to a third embodiment; 
           [0053]      FIG. 6  is an elevation view of a carriage carrying two bumper skins that are superposed, according to a fifth embodiment; and 
           [0054]      FIG. 7  is a diagrammatic elevation view of a movable rack carrying a plurality of bumper skins (shown here without any separators), suitable for use in combination with the temporary storage device of  FIG. 5 . 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0055]    In the drawings, the human figures that are shown diagrammatically serve to provide a dimensional reference. 
         [0056]    In  FIG. 1 , the temporary storage device  1  is constituted by a frame  3  having four pairs of rails  5  mounted thereon to form four storage levels. Each pair of rails  5  are slightly angled so that carriages  7  sliding on the rails have a natural tendency to move in the directions indicated by the arrows  9 . 
         [0057]    On either side of the frame  3 , elevators  11  are vertically movable to load or unload carriages  7  onto or off the pairs of rails  5 . 
         [0058]    Each carriage  7  supports one or more bumper skins  13 , as described in detail with reference to the following figures. 
         [0059]    In  FIG. 2 , two rails  101  and  103  of a pair  5  extend parallel to each other (only a segment of each rail is shown), the rails being spaced apart by a distance of 2 m. The rails are fastened to the frame  3 . Each rail  101 ,  103  is constituted by a metal bar of square section and includes a respective lip  105 ,  107  projecting from its plane and smooth top face  109 ,  111 , from a side thereof. The lips  105  and  107  are arranged on the insides of the rails, i.e. they begin from the respective edges  113 ,  115  of the rails that are the closest to the other rail. This arrangement of the lips  105  and  107  is said to be “inside”. As can be seen better in  FIG. 3 , the lips  105 ,  107  slope inwards (i.e. towards each other), e.g. forming an angle of 45 degrees relative to the horizontal. 
         [0060]    Thus, each lip  105 ,  107  forms a sloping abutment beside the smooth top face  109 ,  111  of each rail, which forms a rolling or sliding track for the bearings of a carriage. 
         [0061]    In  FIG. 2 , the carriage  117  is a sliding carriage. It has a tray  119  with two legs  121  and  123 , each of which possesses a skid  125 ,  127  constituting a bearing resting on the smooth and plane top face  109 ,  111  of a rail  101 ,  103 . The interface between each skid  125 ,  127  and the corresponding rolling track  109 ,  111  is adapted to limit friction between these two surfaces. 
         [0062]    The carriage is dimensioned so as to rest on the rails solely via its skids  125 ,  127  so that it can slide easily in the longitudinal direction. 
         [0063]    The inclined lips  105  and  107  ensure that the skids  125  and  127  cannot easily escape from their sliding tracks. 
         [0064]    Thus, the bearings  125  and  127  are guided along the rails  101  and  103  by the lips  105  and  107  arranged at the margins of the smooth top faces  109  and  111  of the rails, each lip projecting towards the bearing and forming an abutment that prevents the bearing from leaving the rail while moving longitudinally, at least from leaving the rail in a direction perpendicular thereto. 
         [0065]    The carriage  117  presents a longitudinal extent L of 20 cm. The length of the skids must therefore not exceed this maximum extent of length L. Compared with the spacing of 2 m between the rails, the length of the skids is relatively short, thus tending to facilitate a small amount of pivoting of the carriage  117  about a vertical axis  14  on the rails  101  and  103  (“crabbing” of the carriage  117 ). Nevertheless, because of the inclined lips  105  and  107 , the carriage remains on the axis of the rails and slides without jamming thereon. 
         [0066]    The carriage  117  has suspension means in the form of a cover  129  that contains and protects a bumper skin  13 , which skin is thus suspended from the tray  119  of the carriage  117  in the position that it is to occupy on a vehicle (also referred to as its “vehicle position”). The cover  129  also acts as a separator. 
         [0067]    As is known, each bumper skin  13  possesses overriders  14  that give it a shape that is generally C-shaped when seen in plan view while in the vehicle position. This shape facilitates nesting of the bumper skins in pairs. Because of the small longitudinal extent L of each carriage  117 , which is less than the longitudinal extent of a bumper skin in the vehicle position, two adjacent bumper skins  13  can engage one in the other, being separated by the two thicknesses of their covers  129 . In other words, the minimum engagement pitch P of the bumper skins, i.e. their closest engagement (see detail of  FIG. 1 ), is reached before two successive carriages on the rails come into contact via their longitudinal ends, and possibly without them ever coming into contact: the pitch P is therefore greater than the longitudinal dimension of a carriage. In this way, and as can be seen in  FIG. 1 , the loading density of the temporary storage device is optimized, since it depends solely on the shape of the bumper skins and of the separators used, and it is not imposed by the carriages. 
         [0068]      FIG. 3  shows a wheeled carriage  217 , i.e. that has wheels  225  and  227  at the ends of its tray  219 . The carriage  217  is dimensioned so as to rest on the rails solely via its wheels  225  and  227 , which constitute bearings that roll on the smooth top face  109 ,  110  of each rail, which top face then constitutes a rolling surface. 
         [0069]    As with the carriage  117  of  FIG. 2 , the sloping abutments are constituted by lips  105  and  107  that prevent the wheels  225  and  227  from leaving their rolling surfaces  109  and  111 , thereby straightening the carriage  217  should it start “crabbing”. 
         [0070]    This “inside” arrangement of the sloping lips  105  and  107  gives the best results in carriage straightening. 
         [0071]    Thus, the bearings  225  and  227  are guided along the rails  101  and  103  by the lips  105  and  107  arranged at the margins of the smooth top faces  109 ,  111  of each of the rails, each lip projecting towards the support and forming an abutment that prevents the support from leaving the rail while moving longitudinally, at least from leaving the rail in a direction perpendicular thereto. 
         [0072]    In the embodiment of  FIG. 4 , the same carriage  217  is moving on rails  201  and  203  that possess sloping lips  205  and  207  on their outsides, i.e. that begin from the top edges  213  and  215  of each of the rails that are furthest from the other rail. Each lip  205  and  207  slopes outwards, i.e. it extends upwards while going away from the other rail. As before, the lips  205  and  207  serve to hold the wheels  225  and  227  on their rolling surfaces  209  and  211 . 
         [0073]    Thus, the bearings  225  and  227  are guided along the rails  201  and  203  by the lips  205  and  207  arranged at the margins of the smooth top faces  209  and  211  of each of the rails, each lip projecting towards the bearing and forming an abutment that prevents the bearing from leaving the rail while it moves longitudinally, at least from leaving the rail in a direction perpendicular thereto. 
         [0074]    The embodiment of  FIG. 5  is a variant of the embodiment of  FIG. 3 , in which the lips  305  and  307  of the rails  301  and  303  are vertical instead of sloping. The lips  305  and  307  thus form vertical abutments that retain the wheels  225  and  227  on their rolling surfaces  309  and  311  without it being possible for them to rise up the lips in the event of “crabbing” of the carriage  217 . 
         [0075]    Thus, the supports  225  and  227  are guided along the rails  301  and  303  by the lips  305  and  307  arranged at the margins of the smooth top faces  309  and  311  of each of the rails, each lip projecting towards the bearing and forming an abutment that prevents the bearing from leaving the rail while it is moving longitudinally, at least from leaving the rail in a direction perpendicular thereto. 
         [0076]    Selection between the embodiments of  FIGS. 3 and 5 , i.e. between sloping abutments and vertical abutments, depends on the clearances left between the wheels  225 ,  227  and the rails  101 ,  103  or  301 ,  303 . When clearances are very tight, blocking the wheels  225 ,  227  on their rolling surfaces  309 ,  311 , as shown in  FIG. 5 , can give results that are better than allowing them to rise up sloping abutments. In contrast, when clearances are slack, small amounts of pivoting of the carriage are inevitable, and it may be preferable to straighten the carriage more gently by means of sloping abutments that recenter it on the rolling surfaces  109 ,  111  of the rails  101 ,  103  without carriage jamming. 
         [0077]      FIG. 6  shows a carriage  7  on a portion of a pair of rails  5 , the carriage  7  being provided with suspension means in the form of covers  229 . Each cover  229  serves to suspend one bumper skin and possesses, in its bottom portion, fasteners enabling another, identical cover to be fastened thereto. Thus, in  FIG. 6 , two covers are suspended one above the other from a single carriage of the type described above. 
         [0078]      FIG. 7  shows a movable rack  15  designed to transport bumper skins in transport vehicles, in particular trucks. Such a movable rack  15  may be used in combination with the stationary temporary storage device  1  thanks to its ability to receive carriages  117  or  217  and covers  129 ,  229  that are identical to those described above. In the example shown, four levels of covers  229  are mounted on the rack  15 . Thus, the bumper skins are packaged in the same manner both for temporary storage and for transport, and loading/unloading carriages on and off the storage device is made easier, thereby reducing handling while increasing loading density during transport. 
         [0079]    Naturally, the embodiments described above are not limiting in any way the scope of the invention and they may receive any desirable modification without going beyond the scope of the claims. 
         [0080]    While the process, device, product and system herein described constitute preferred embodiments of this invention, it is to be understood that the invention is not limited to this precise process, device, product and system, and that changes may be made therein without departing from the scope of the invention which is defined in the appended claims.