Abstract:
A motor vehicle having an instrument panel that is spaced rearward away from a bottom end of a windscreen so that it is less likely to be damaged in the event of a frontal impact. A cover is attached to vehicle body structure adjacent to the bottom end of the windscreen to cover the gap produced by spacing the instrument panel from the bottom of the windscreen. The cover overlies an upper surface of the instrument panel and slides rearward over the upper surface when the bottom end of the windscreen moves rearward into the crush space during a collision.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims foreign priority benefits under 35 U.S.C. §119(a)-(d) to GB 1512666.7 filed Jul. 20, 2015, which is hereby incorporated by reference in its entirety. 
     TECHNICAL FIELD 
     This invention relates to a motor vehicle having an instrument panel. 
     BACKGROUND 
     It is well known to provide a motor vehicle with an instrument panel (often alternatively referred to as a dashboard) mounted in a passenger compartment of the motor vehicle and extending across the width of the passenger compartment of the motor vehicle. 
     Various instruments are mounted in the instrument panel and it also often houses ducting for part of a ventilation system of the motor vehicle and in some cases one or more airbags 
     SUMMARY 
       FIG. 1  is a schematic side view of a prior art motor vehicle  1  showing a conventionally mounted instrument panel  10  in a passenger compartment  6  of the motor vehicle  1 . The motor vehicle  1  comprises a roof  2 , a floor  3 , a windscreen  4  and a firewall or bulkhead  5  separating the passenger compartment  6  from a front compartment  7 . In a motor vehicle having a front mounted engine the engine is mounted in the front compartment  7  and in a motor vehicle having a rear mounted engine the front compartment  7  forms a luggage storage area. 
     A windscreen frame (not shown) for housing the windscreen  4  is joined at a bottom end to other structural components of the motor vehicle  1  including the bulkhead  5 . 
     The instrument panel  10  is mounted on the bulkhead  5  or is mounted on a cross-vehicle beam (not shown), in either case, the instrument panel  10  abuts against a bottom end of the windscreen  4 . 
     In the event of a severe frontal collision a front end of the motor vehicle  1  is designed to crush so as to absorb energy as is well known in the art. 
     For small vehicles and, particularly, small rear-engined vehicles, maximum utilization of the available crush space is critical in order to deliver good crash performance. Where the available crush length is small such as A-class and City vehicles there may be some level of intrusion to the structure supporting the bottom of the windscreen if the frontal impact is severe. That is to say, a bottom end of the windscreen is located within a front crush zone of the motor vehicle. Such intrusion can result in parts of the instrument panel becoming detached or breaking and thereby constituting a risk to an occupant of the motor vehicle. 
     It is an object of the invention to reduce the risk of instrument panel damage in the event of a frontal collision. 
     According to the invention there is provided a motor vehicle having a body structure defining a passenger compartment, an elongate instrument panel mounted in the passenger compartment, a windscreen having a bottom end attached to the body structure of the motor vehicle wherein the instrument panel is spaced away from the bottom end of the windscreen so as to define a gap therebetween and a cover is provided to cover the gap between the bottom end of the windscreen and an upper surface of the instrument panel. 
     The body structure may include a bulkhead separating the passenger compartment from a front compartment of the motor vehicle and the instrument panel may be spaced away from the bulkhead. 
     The instrument panel may only be connected at each end to the body structure of the vehicle. 
     The instrument panel may include a mounting beam that is used to support the instrument panel and connect the instrument panel at each end to the body structure of the vehicle. 
     The cover may have a first end connected to the body structure of the motor vehicle adjacent to the bottom end of the windscreen and a second end that is positioned during normal use upon the upper surface of the instrument panel. 
     If the longitudinal dimension of the gap between the bottom end of the windscreen and the instrument panel reduces, the second end of the cover may be arranged to slide over the upper surface of the instrument panel. 
     The bottom end of the windscreen may be located in a front crush zone of the motor vehicle and the gap may position the instrument panel away from the bottom end of the windscreen out of the front crush zone of the motor vehicle. 
     The motor vehicle may be a rear-engined motor vehicle. 
     The invention will now be described by way of example with reference to the accompanying drawing of which: 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a schematic side view of a prior art motor vehicle showing a conventionally mounted instrument panel in a passenger compartment of the motor vehicle; 
         FIG. 2  is a schematic side view similar to  FIG. 1  but showing how an instrument panel is mounted in a passenger compartment of a motor vehicle constructed in accordance with the invention; 
         FIG. 3  is a schematic view in the direction of arrow X on  FIG. 2 ; 
         FIG. 4  is side view similar to  FIG. 2  but showing in more detail the positioning of the instrument panel and a cover used to bridge a gap between the instrument panel and a bottom end of a windscreen of the motor vehicle; and 
         FIG. 5  is an enlarged cross section in the region “R” on  FIG. 4  showing a living hinge forming part of the cover. 
     
    
    
     DETAILED DESCRIPTION 
     As required, detailed embodiments of the present invention are disclosed herein; however, it is to be understood that the disclosed embodiments are merely exemplary of the invention that may be embodied in various and alternative forms. The figures are not necessarily to scale; some features may be exaggerated or minimized to show details of particular components. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a representative basis for teaching one skilled in the art to variously employ the present invention. 
     With reference to  FIGS. 2 to 5  there is shown a small rear-engined motor vehicle  101  having a roof  102 , a floor  103 , a windscreen  104  and a firewall or bulkhead  105  separating a passenger compartment  106  from a front compartment  107 . In this case, because the motor vehicle  101  has a rear mounted engine (not shown), the front compartment  107  forms a luggage storage area for the motor vehicle  101 . 
     A distance “D” from a front end of the motor vehicle  101  to a bottom end of the windscreen  104  is small so that a corresponding crush distance (CD 1  on  FIG. 4 ) is small. 
     A windscreen frame for housing the windscreen  104  is structurally joined at a bottom end to other structural components of the motor vehicle  101  forming part of a body structure of the motor vehicle  101  such as the bulkhead  105 . 
     An instrument panel  110  is mounted on a laterally-extending cross-vehicle beam  115  that is connected at opposite lateral ends to part of the body structure of the motor vehicle  101 . 
     The instrument panel  110  is connected at each end to the body structure of the vehicle via the mounting beam  115  which both supports the instrument panel  110  and connects it at each end to the body structure of the vehicle  101 . The instrument panel  110  extends across the entire width of the passenger compartment  106 . The instrument panel  110  is spaced away from the bulkhead  105  and there are no structural connections between the bulkhead  105  and the instrument panel  110 . 
     The windscreen  104  of the motor vehicle  101  has a bottom end attached via a bonding strip  109  to the body structure of the motor vehicle  101 . The instrument panel  110  is spaced away from the bottom end of the windscreen  104  so as to define a gap “G” therebetween and a cover  120  made from a plastic material is provided to cover the gap “G” between the bottom end of the windscreen  104  and an upper surface  110   u  of the instrument panel  110 . 
     As best seen in  FIGS. 4 and 5  the cover  120  has a first/rear end  121  that rests upon the upper surface  110   u  of the instrument panel  110  or, to be more precise, upon trim forming the upper surface of the instrument panel  110  and has a second/front end  122  connected to a fastening member which in this case is in the form of an elongate fastening strip  123  used to connect the cover  120  to part of the body structure of the motor vehicle  101 . It will be appreciated that prior to impact the cover  120  may be attached to the instrument panel  110  in a frangible manner to prevent rattling. The attachment of the cover  120  to the instrument panel  110  is easily broken when a load is applied to it so as not to prevent sliding of the cover  120 . 
     A living hinge  124  provides a rotatable connection between the second/front end  122  of the cover and the fastening strip  123 . 
     It will be appreciated that the cover  120 , the fastening strip  123  and the living hinge  124  are all formed as integral parts of a single component made from a plastic material. 
     In  FIG. 4  when the cover is in a pre-impact position it is indicated by the reference number  120  when the cover is in a post impact position it is shown in dotted outline referenced  120 ′. Note that only the cover  120 ′ is shown in the post impact position and not the support structure for the cover  120 ′. 
     The post impact position corresponds to a situation where the bottom end of the windscreen  104  has moved back and the gap “G” between the bottom end of the windscreen  104  and the instrument panel  110  has been absorbed by the impact. It will be appreciated that the instrument panel  110  has not moved it is the relative movement between the bottom end of windscreen  104  and the instrument panel  110  that results in a diminishing in the longitudinal dimension of the gap “G”. 
     Because the cover  120  rides up onto and slides across the upper surface  110   u  of the instrument panel  110  no significant force is transferred to the instrument panel  110  until all the gap “G” is absorbed. The longitudinal dimension of the gap “G” is therefore set to be as large as possible taking into account packaging constraints for the instrument panel  110  such as the distance required between the instrument panel  110  and any occupants of the motor vehicle  101 . The longitudinal dimension of the gap “G” is set so as to move the instrument panel  110  out of a front crush zone CZ of the motor vehicle  101 . 
     The longitudinal dimension of the gap “G” is typically, by way of example and without limitation, in the range of 0.020 to 0.120 m as such a gap provides a good compromise between packaging and improved crash properties. 
     In  FIG. 4  the difference in available crush distance between a motor vehicle having an instrument panel mounted adjacent to a bottom edge of a windscreen and a motor vehicle constructed in accordance with this invention having the instrument panel mounted so that a gap is present is shown. 
     In the case of a prior art motor vehicle the available crush distance is shown as CD 1 . When the crush distance CD 1  is used up due to collapse of the front of the vehicle resulting from a frontal impact, a considerable force will be transferred from the body structure of the motor vehicle into the instrument panel because it abuts the lower edge of the windscreen  104 . 
     In the case of a motor vehicle constructed in accordance with this invention, an available crush distance CD 2  is provided. Therefore, it is not until the increased crush distance CD 2  is used up will any force be transferred from the body structure of the motor vehicle  101  into the instrument panel  110 . The difference in crush distance ΔCD between CD 2  and CD 1  corresponds to the longitudinal dimension of the gap “G” between the bottom end of the windscreen  104  and the instrument panel  110  as shown in  FIG. 2 . The corresponding crush zone CZ for the motor vehicle  101  for a predefined serious crash condition will be greater than CD 1  but less than CD 2  as indicated by the double headed arrow CZ on  FIG. 4 . 
     The function of the cover  120  is to cover the gap “G” between the bottom end of the windscreen  104  and the instrument panel  110  so as to provide an aesthetically pleasing appearance and to prevent objects placed upon the upper surface  110   u  from falling down behind the instrument panel  110 . 
     Although the invention has been described with reference to an instrument panel that is supported by a structural beam it will be appreciated that other types of construction could be used for the instrument panel so as to provide it with sufficient rigidity and strength to be supported only at each end. For example and without limitation, the instrument panel can include a skeletal body that is used to support the instrument panel and connect the instrument panel at each end to the body structure of the vehicle. For example, the instrument panel could have a die cast core and an overlying fascia member. See for example the instrument panel construction disclosed in Patent Publication WO2005/021362. 
     Furthermore the invention is not limited to the use of a living hinge other types of connection allowing the cover to rotate relative to the body structure so as to allow it to ride up onto and slide across the upper surface of the instrument panel could be used such as, for example, one or more conventional mechanical hinges. Alternatively, the cover could have a first end attached to the body structure near the bottom end of the windscreen and a second end resting upon the upper surface of the dashboard during normal use and be made from a resilient flexible material enabling it to flex or bend sufficiently near its first longitudinal edge to permit the second edge to slide over the upper surface of the instrument panel when the gap is reduced due to a frontal impact. 
     As yet another alternative the cover could have a first end attached to the body structure near the bottom end of the windscreen, a second end attached to the instrument panel and have a number of corrugations running substantially parallel to the lower end of the windscreen. The corrugations facilitate the easy collapse of the cover between the first and second ends when the longitudinal dimension of the gap between the bottom end of the windscreen and the instrument panel reduces. 
     The connection means used to attach the cover to the body structure in all cases is such that it tethers the cover to the body structure during a frontal impact. 
     It will be appreciated by those skilled in the art that although the invention has been described by way of example with reference to one or more embodiments it is not limited to the disclosed embodiments and that alternative embodiments could be constructed without departing from the scope of the invention as defined by the appended claims. 
     While exemplary embodiments are described above, it is not intended that these embodiments describe all possible forms of the invention. Rather, the words used in the specification are words of description rather than limitation, and it is understood that various changes may be made without departing from the spirit and scope of the invention. Additionally, the features of various implementing embodiments may be combined to form further embodiments of the invention.