Abstract:
A chassis of a vehicle, the chassis is provided with a pair of door sills arranged longitudinally under the door zone and each having a through hole, and a pair of central pillars, each of which raises perpendicularly and vertically from a door sill, is made of one piece, is inserted in an interlocking way in the through hole of a window sill and is welded to the window sill at the through hole.

Description:
RELATED APPLICATION 
       [0001]    This application claims the benefit of priority under 35 U.S.C. Section 119 to Italian Patent Application Serial No. B02009A 000492, filed on Jul. 28, 2009, which is incorporated herein by reference in its entirety. 
       TECHNICAL FIELD 
       [0002]    The present subject matter relates to a chassis of a vehicle. More specifically, the present subject is advantageously applied to the chassis of an automobile, to which explicit reference will be made in the following description without limitation. 
       BACKGROUND 
       [0003]    A chassis of an automobile normally consists of a central body, forming the passenger compartment, and a front body supporting the front wheels and a rear body supporting the rear wheels. The engine may be arranged in frontal position, and thus accommodated in the front body, or in central or rear position, and thus accommodated in the rear body. 
         [0004]    At the passenger compartment and approximately in the middle of the automobile, the chassis comprises two central pillars, each of which rises vertically from a door sill and ends at the roof. In most automobiles on the market, each side (e.g., comprising the door sill and the central pillar) is made of several pressed parts, which are superimposed and welded. Such a constructive method is fast and cost-effective when the material used for the chassis is steel and/or when a high number of parts are made (i.e. for mass manufactured automobiles), while it is more complex and costly when the material used for the chassis is aluminum and/or when a low number of parts are made (i.e. for small series automobiles). 
         [0005]    Patent application EP1498345A2 describes a vehicle provided with a pair of door sills arranged longitudinally underneath the zone of the doors, and each having a through hole; and a pair of central pillars, each of which raises perpendicularly and vertically from a door sill, is made in one piece, is inserted in an interlocking way in the through hole of a window sill, and is welded to the window sill at the through hole. 
       SUMMARY 
       [0006]    Some examples provide a chassis for a vehicle, which is free from drawbacks described above, and which is thus easy and cost-effective to make when the material used for the chassis is aluminum and/or when a low number of parts are made (i.e. for small series vehicles). 
         [0007]    According to some examples, a chassis of a vehicle is provided as claimed in the attached claims. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0008]    The present invention will now be described with reference to the accompanying drawings, which illustrate a non-limitative embodiment thereof, in which: 
           [0009]      FIG. 1  is a diagrammatic, perspective view of a chassis of a vehicle made in accordance with some examples; 
           [0010]      FIG. 2  is a perspective view of a door sill and a central pillar of the chassis in  FIG. 1 ; 
           [0011]      FIG. 3  is a perspective, exploded view of the door sill and of the central pillar in  FIG. 2 ; and 
           [0012]      FIG. 4  is a perspective bottom view of the door sill and of the central pillar in  FIG. 2 . 
       
    
    
     DETAILED DESCRIPTION 
       [0013]    In  FIG. 1 , numeral  1  indicates as a whole a chassis of an automobile comprising a central body  2 , in which a passenger compartment is defined, a front body  3 , in which a luggage compartment, also known as a trunk or boot, is defined, and rear body  4 , in which an engine compartment is defined. In various examples, the front body  3  and the rear body  4  are bolted to the central body  2  so as to be disassembled if needed. Furthermore, according to certain examples, the chassis  1  comprises a floor pan (not shown), which is inferiorly (i.e., under) bolted at least to the central body  2 . 
         [0014]    The central body  2  of the chassis  1  is made of aluminum by welding several components, and in particular the central body  2  comprises a plurality of linear bars, which display a constant section, are made by extrusion, and are joined together by welding at structural nodes defined by junction bodies. Each junction body has a number of respective pockets (not shown in detail), which are adapted to elongate the head of corresponding linear bars. In particular, four junction bodies are present (two front junction bodies and two rear junction bodies) at the attachment zone of each suspension. 
         [0015]    Two linear bars of the central body  2  arranged longitudinally underneath the door zone form the door sills  5  (i.e. the lower part underneath the doors which extends from the end of the front wheel arch to the beginning of the rear wheel arch). A central pillar  6  rises perpendicularly and vertically from each door sill  5 , which extends from the door sill  5  to an upper bar which is arranged longitudinally and defines a side end of the roof. 
         [0016]    As shown in  FIG. 2-4 , each central pillar  6  consists of a one-piece or monolithic extrusion (i.e. free from parts added by welding, screwing, riveting or other mechanical connection methods). Each door sill  5  has a through hole  7 , in which a central pillar  6  is inserted in an interlocking way; furthermore, each central pillar  6  is welded to the door sill  5  at the through hole  7 . 
         [0017]    Each central pillar  6  comprises an internal tubular body  8  inserted coaxially inside an external tubular body  9 ; both bodies  8  and  9  have a rectangular transversal section and are connected to one another by means of two flat plates  10 , which connect the internal tubular body  8  to the external tubular body  9  and are arranged reciprocally coplanar on opposite sides of the internal tubular body  8 . 
         [0018]    In some examples, the internal tubular body  8  of each central pillar  6  extends along the extension of the central pillar  6  itself, while the external tubular body  9  of each central pillar  6  extends only along a lower portion of the central pillar  6  itself arranged at the door sill  5  (in particular, the external tubular body  9  of each central pillar  6  extends inside the door sill  5  and partially even outside the door sill  5 ). This shape of each central pillar  6  allows to obtain high mechanical strength at door sill  5  (i.e. when the main mechanical stress occurs) combined with a low total weight. 
         [0019]    In order to reduce the weight of each central pillar  6 , the two flat plates  10  of each central pillar  6  have windows  11  (i.e. reliefs made by eliminating material) arranged outside the external tubular body  9 . 
         [0020]    Underneath, each central pillar  6  is inserted in an interlocking way inside a hole  7  of a door sill  5  and is also welded to the door sill  5 ; superiorly (i.e., above), each central pillar  6  is fixed to an upper part of the chassis  1 . The fastening of each central pillar  6  to the upper bar may be similar to the fastening of the central pillar  6  to the door sill  5  (thus the upper bar has a through hole which accommodates the central pillar  6 , which is also welded to the upper bar itself), or the central pillar  6  may also be welded to the upper bar. 
         [0021]    According to some examples, each door sill  5  is initially made in one piece by extrusion and then mechanically machined by elimination of material to remove the unnecessary parts (i.e. by mechanically cutting part of the external tubular body  9  and mechanically cutting the plates  10  to make the windows  11 ). 
         [0022]    The above-described chassis  1  has many advantages. 
         [0023]    Firstly, the above-described chassis  1  is very robust with respect to side collisions because it has very high mechanical strength in the connection between the door sill  5  and a central pillar  6 ; in particular, such as result is obtained by mechanically inserting the central pillar  6  in the through hole  7  of the door sill  5  in an interlocking way. 
         [0024]    Furthermore, the above-described chassis  1  is simple and cost-effective to make, also when the material used for the chassis is aluminum. 
         [0025]    Finally, the above-described chassis  1  is simple and cost-effective to make, also when a low number of parts is made (i.e. for small series automobiles).