Patent Publication Number: US-2013251475-A1

Title: Device for fastening door or flap hinges or other elements to the doors or flaps or to the bodywork of motor vehicles

Description:
TECHNICAL AREA 
     The present invention relates to devices for fastening door or flap hinges or other elements, such as side impact supports, to the doors or flaps or to the bodywork of motor vehicles. 
     PRIOR ART 
     Generally, side impact supports or door hinges of this type are fastened to the panel of the door and to the panel of the bodywork by means of one or more screws and associated nuts. The fastening according to the prior art, as shown in  FIG. 1 , leads to a rigid connection which, in particular, in the event of a side impact accident has to absorb the entire loads. The drawback of a rigid connection of this type is that the deformable region is exclusively described by the configuration of the door itself. No additional movement is possible to absorb kinetic energy from the object penetrating laterally. This also means that the connection of the door hinge has to absorb the entire energy introduced. It is known from earlier crash tests with doors that the connection is frequently destroyed in the event of side impact accidents in that, for example, the screw and nut are pulled out of the panel material of the door. 
     The object of the present invention is therefore to improve the fastening of door or flap hinges or side impact supports on the doors or flaps or on the bodywork of motor vehicles in such a way that these fastenings can absorb energy and the load on the door panel and the opposing bodywork panel can thereby be reduced, and to simultaneously reduce the deformation energy in a controlled manner in the event of a side impact. 
     PRESENTATION OF THE INVENTION 
     According to the invention, this object can be achieved, for example, in that arranged between the nut and the panel of the door, the flap or the bodywork or the side impact support or the hinge is a hollow absorber element, which is penetrated by the screw and has side walls, which substantially run parallel to the rotational axis of the screw, namely abutment faces in each case running perpendicular to the rotational axis of the screw, one abutment face being supported on the panel of the door, the flap or the bodywork or the hinge, while the other abutment face carries the nut. 
     To simplify the production, it is preferred here for the absorber element to be hollow cylindrical, so the side walls form the lateral surface of the cylinder. 
     In order to achieve easier and more controlled deformation of the absorber element in the event of an accident, it is particularly preferred for the side walls to be configured with a corrugated profile or be pre-compressed. 
     On the other hand, if it is wished to achieve a higher absorption of energy of the absorber element, it is preferred if the absorber element is completely or partly filled with a foam, for example a foamed plastics material, such as polyurethane foam. 
     It may be advantageous from the manufacturing point of view, if the absorber element is welded to the panel of the door, the flap or the bodywork or the side impact support or the hinge. 
     A particularly high stability of the absorber element can be achieved if the abutment face, which faces the panel of the door, the flap or the bodywork or the side impact support or the hinge, of the absorber element is formed by a guide plate welded to the side walls. 
     A particularly economical and simple production is produced if the abutment face, which faces the panel of the door, the flap or the bodywork or the side impact support or the hinge, is formed by a right-angled folded edge of the side walls. 
     Furthermore, the production can be facilitated in that the nut is made captive by being welded, soldered, riveted or glued to the abutment face facing it. 
     In order as far as possible to avoid a jamming of the door in the event of an accident, it is particularly preferred if the panel of the door, the flap or the bodywork and the hinge is in each case provided with one or more guides, for example by openings, which oppose one another in each case in the assembled state, are virtually the same size and through which pins are inserted in the assembled state. It can thus be ensured that the side impact support or the hinge remains in its place even in the event of a deformation of the absorber element and, in this manner, the door is prevented from jamming. 
     It is particularly preferred here if the pins are additionally supported on the inner face of the side walls. 
     Alternatively, the object according to the invention can also be achieved in that the screw additionally extends through a hollow absorber element, which has side walls, which extend substantially parallel to the rotational axis of the screw, an abutment face, which runs perpendicular to the rotational axis of the screw and is supported on the panel of the door, the flap or the bodywork or the side impact support or the hinge, and an internal thread for the screw on the side opposing the abutment face. 
     From the manufacturing point of view it is also particularly preferred here to make the absorber element hollow cylindrical, so the side walls form the lateral surface of the cylinder. 
     In order to ensure a particularly well controlled deformation, the side walls may be configured with a corrugated profile or be pre-compressed. 
     If a particularly high absorption of energy of the absorber element is desired, the latter can be completely or partly filled with a foam, for example a foamed plastics material, such as polyurethane foam. 
     To simplify the assembly, the absorber element can be welded, soldered, riveted or glued to the panel of the door, the flap or the bodywork or the side impact support or the hinge. 
     A particularly stable embodiment of the absorber element is produced when the abutment face of the absorber element is formed by a guide plate welded to the side walls. 
     Particularly simple production is made possible when the abutment face is formed by a right-angled folded edge of the side walls. 
     Especially in this embodiment of the invention, a particularly economical production emerges when the absorber element is produced as a sheet metal formed part, and the internal thread is configured in a tube. 
     In order to achieve particularly great side stability of the fastening according to the invention, it is preferred that the panel of the door, the flap or the bodywork and the hinge or the side impact support be provided, in each case, with one or more guides, for example by openings, which oppose one another in each case in the assembled state, are virtually the same size and through which pins are inserted in the assembled state. 
     These pins are preferably additionally supported on the inner face of the side walls. 
    
    
     
       SHORT DESCRIPTION OF THE FIGURES OF THE DRAWINGS 
       The present invention will be described in more detail below with the aid of the embodiments shown in the drawings. 
       In the drawings: 
         FIG. 1  shows a door connection according to the prior art; 
         FIG. 2  shows a door connection with separate nut, welded absorber element and guide pins in the assembled state; 
         FIG. 3  shows the embodiment of  FIG. 2  after an accident, in which the absorber element has deformed; 
         FIG. 4  shows a further embodiment of the fastening according to the invention, in which the absorber element is configured as a panel component with a welded guide plate, in the assembled state, and 
         FIG. 5  shows the embodiment of  FIG. 4  after an accident, which has led to the deformation of the absorber element. 
     
    
    
     BEST METHOD FOR CARRYING OUT THE INVENTION 
     For better explanation of the present invention,  FIG. 1  firstly shows the fastening of a door hinge  10  to a door panel  12 , corresponding to the previous prior art. The fastening takes place here by means of a screw  14 , which extends through a respective opening in the door hinge  10  and the door panel  12  and which is screwed on the side opposing its head using a nut  16 , preferably a weld nut. The same reference numerals will be used below for the same components, in order to increase the comprehensibility of the description. 
       FIG. 2  shows a first embodiment according to the invention of a door fastening. The door hinge  10  is also connected here to the door panel by means of a screw  14 ′, which, in each case, extends through a respective opening in the hinge  10  and the door panel  12  and is screwed by means of a nut, preferably a weld nut  16 . This screw  14 ′ has to be longer here than in the prior art. 
     An absorber element  18  is namely arranged here between the nut  16  and the door panel  12  according to the invention. Said absorber element is in the form of a hollow cylinder and the side walls  20  of the absorber element  18  are formed here by the lateral surface of the hollow cylinder. These side walls  20  are arranged coaxially here with respect to the rotational axis of the screw  14 ′. The top face  22  remote from the door panel  12  forms the abutment for the nut  16 . The screw  14 ′ penetrates the hollow cylindrical-shaped absorber element  18  coaxially and extends through an opening  24  in the absorber element  18  and out of it. In order to be able to achieve easier deformability of the absorber element  18 , the side walls  20  may be configured with a corrugated profile or be pre-compressed. 
     Depending on the requirements in relation to assembly, the screw  14 ′ can, of course, also be installed the other way round, in other words, the head of the screw  14 ′ is then supported on the top face  22  of the absorber element  18 , while the nut rests on the door hinge  10 , or, if it is configured as a weld nut, it can be welded there. The absorber element  18  is supported by means of a right-angled folded edge  26  on the door panel  12 . In order to simplify the production, these folded edges  26  are directed outwardly. They form a circular ring-shaped support face for the absorber element  18 , with which the latter is supported on the door panel  12 . In addition, the absorber element  18  may be fastened on the door panel  2  by means of a weld seam  28 . Alternatively, gluing, riveting or another connection method is also possible. 
     For further stabilisation of the fastening device according to the invention in the event of an accident, a guide is additionally provided here, for example two pins  30 , which also extend through respective opposing openings in the door hinge  10  and the door panel  12 . Furthermore, these pins  30  are supported on the inside of the side walls  20  of the absorber element  18  and thereby stabilise the latter. 
     The pins are shown here with a circular cross-section. However, they may also have another cross-section if this is structurally advantageous. The pins may be fastened here in a press fit in the door panel  12  or in the hinge  10 , or be glued there. The number of pins  30  is variable here; two, three or four pins may be provided and, in the event of lower requirements for preventing the fastening device from tilting in the case of a collision, the pins  30  can also be dispensed with completely, as the embodiment of  FIGS. 4 and 5  will show below, by way of example. 
       FIG. 3  shows the fastening device of  FIG. 2  according to the invention after an accident, for example a side impact against the door fastened with the device according to the invention. 
     The absorber element  18  has been deformed here by compression of the side walls  20 , energy having been absorbed accordingly. A spacing “crumple zone”  32  has formed between the door hinge  10  and the door panel  12 , the size of which depends on the energy absorbed and the configuration of the side walls  20  of the absorber element  18 . The pins  30  are still rigidly inserted in the door panel  12  and still guide the door hinge  10 , so the latter cannot tilt, which otherwise generally leads to a jamming of the doors in the event of accidents. 
     As can be seen very nicely from this  FIG. 3 , the fastening device according to the invention leads to a controlled deformation with the absorption of energy and therefore to a controlled deformation event of the entire door region in the event of a side impact. 
       FIG. 4  shows a further embodiment of a fastening device according to the invention. The same reference numerals also designate the same components here as in  FIGS. 1 to 3 . 
     In the embodiment shown in  FIG. 4 , the nut  16  of  FIGS. 2 and 3  is, however, replaced by a tube  36 , into which an internal thread for the screw  14 ′ is introduced. In this manner, the absorber element  20  can be produced in one piece as a sheet metal formed part and the use of an additional nut  16  can be saved. 
     Furthermore, the absorber element  18 ′ shown is supported by means of a guide plate  34  on the door panel  12 . The guide plate has the form of a circular disc, which has a circular attachment  38 , which extends away perpendicularly from the door panel  12  and is used as an abutment for the side walls  20  of the absorber element  18 ′. The connection between the side walls  20  of the absorber element  18 ′ and the guide plate  34  is preferably ensured by a further weld seem  28 . Furthermore, the absorber element  18 ′ can also be connected here by means of its guide plate  34  by a further weld seam  28  to the door panel  12 . 
     Alternatively, the element can also be produced in one piece, a combination of  FIGS. 2 and 4  with the tube  36  and the right-angled edge  26  in one element. 
     No pins ( 30 ) are provided in the embodiment shown here. 
       FIG. 5  shows the fastening device according to the invention of  FIG. 4  after the loading by a side impact. The side walls  20  of the absorber element  18 ′ have also deformed here by absorbing energy. A lateral bending away of the absorber element  18 ′ is not prevented here by pins  30 , but by the welding to the guide plate  34 . The door hinge  10  and door panel  12  have also moved apart from one another here in a controlled manner by a spacing “crumple zone” after the collision-related loading. 
     If the absorption of energy of the absorber element  18 ,  18 ′ is to be increased in the two embodiments, the absorber element can be completely or partly filled with a plastics material foam, for example polyurethane foam.