Abstract:
A rear spoiler device for a vehicle, such as a utility vehicle or a trailer, includes at least one adjustable air guiding element for aerodynamically guiding air and extending the contour of the lateral region of the rear of the vehicle. The guide element is adjustable between a travel position, in which it extends rearwards in a lateral region of the rear for aerodynamically guiding air and extending the contour, and a stowed position. The air guiding element is spring pre-loaded into the extended travel position and is adjusted into the stowed position by pressing the guide element from the rear side counter against the spring pre-load.

Description:
FIELD OF THE INVENTION 
     The invention generally concerns a rear spoiler device for a vehicle, such as for a utility vehicle or a trailer. 
     BACKGROUND OF THE INVENTION 
     Utility vehicles such as heavy goods vehicles or buses, or trailers of heavy goods vehicles, generally have a box shape, which allows for effective use of available loading space and direct access to the loading space via the rear. During travel, however, the box shape leads to severe breakaway turbulence behind the rear of the vehicle and, hence, to poor aerodynamic properties. Rear spoilers serve to improve the aerodynamics of a vehicle and can reduce fuel consumption, accordingly. 
     For this, DE 10 2009 014 860 A1 proposes forming a rear spoiler for a utility vehicle on the sides and upper edge of the rear with several adjustable air guiding surfaces, which are substantially curved inward and adjustable separately in order to adapt automatically to the respective air flow during travel. 
     Some utility vehicles have attachments with an access opening at the rear, which is closed by a roller shutter. Such vehicles can generally be reversed up to a ramp without the driver first having to get out in order to open the roller shutter. With rear spoiler designs such as described in DE 10 2009 014 860 A1, reversing up to a ramp is problematic due to the air guide surfaces protruding at the rear. 
     SUMMARY OF THE INVENTION 
     Generally speaking, it is an object of the present invention to provide a rear spoiler device for a vehicle that permits easy access to the rear of the vehicle. 
     The present invention is based on the concept of allowing automatic movability of the lateral rear spoiler device by mechanical contact at, e.g., a docking station during a reversing approach or parking process. Here, movement is possible between a travel position, in which the air guiding element(s) form(s) the aerodynamically advantageous contour extension towards the rear, and a stowed position or unloading position with the air guiding element(s) lying fully or largely against the rear. 
     The stowed position serves for loading and unloading of the vehicle via the rear access opening, and is established on a reverse approach to an object. 
     Thus, the driver can reverse the vehicle up to a ramp or loading station so that, on contact with the ramp or loading station, the rear spoiler device moves or is retracted or folded in automatically without the driver needing to get out. This is advantageous in particular in the case of a vertically opening closure on the rear of the vehicle, e.g., a shutter door or a vertically liftable tarpaulin. Once at the ramp or loading station, the rear access door can be opened without interference from the rear spoiler device, the vehicle can be loaded and/or unloaded in the conventional manner, and then, after closing the rear access opening, the vehicle can be driven away, with the lateral rear spoiler device or the air guiding element(s) moving automatically into the travel position. 
     A center rear spoiler device can be arranged between lateral rear spoiler devices on the roof or upper edge of the rear, and, e.g., remain unchanged if it does not hinder the loading and unloading process. 
     Advantageously, in the retracted stowed position, the air guiding element(s) do(es) not protrude disruptively towards the middle, i.e., towards the rear access opening. For this, the rear spoiler device advantageously has a shift mechanism, preferably an articulated rod mechanism, which allows the movement of the air guiding element(s) between the stowed and travel positions, and, advantageously, also creates spring loading. The shift mechanism can guide the air guiding element(s) outwardly on folding, so that, in folded state, it/they do(es) not block the access opening to the rear. 
     Thus, longer air guiding elements, which allow more favorable aerodynamic properties, can also be used without blocking the access opening. Air guiding element length is not limited in principle according to the present invention. 
     The articulated rod mechanism can be formed by two rods, of which the first, front rod is hinged directly or indirectly to the vehicle frame or part of the vehicle frame, and the rear, second rod is hinged to the first rod and, in turn, holds an air guiding element. Advantageously, the two rods have different lengths; in the travel position, the first rod extends rearward and laterally outward, whereupon the second rod extends rearward and towards the middle. The first rod is preferably longer than the second rod, e.g., the length of the first rod is approximately equal to the sum of the lengths of the second rod and a region of the air guiding element between its connecting hinge on the second rod and its rear end. 
     Such an articulated rod mechanism can be achieved with relatively few components, e.g., only the first and second rods, and suitable stops to establish the travel position and the angular positions in the travel position, and corresponding springs. Advantageously, springs are provided in the three hinges to allow a dynamic shift between the different positions on a reversing approach. For this, e.g., the air guiding element can be swiveled on contact with the ramp and come into its relatively flat stowed position, and then the rods can be folded in. Here, the shift mechanism can be formed by several such articulated rod mechanisms, which can be provided vertically spaced between the frame and the air guiding element. 
     Because of the foldability, in particular on the rear hinge, the air guiding element can swivel when loaded by the contact. Its inwardly curved form here allows a relatively gentle roiling of the air guiding element on the ramp or resistance so that no extensive mechanical damage is expected, and even on harder impacts, a flexibility is achieved due to the multipiece hinge mechanism, in particular also the angles between the rods. 
     Production of the rear spoiler device is also favorable, e.g., in an embodiment with a larger air guiding element, made, for example, from plastic, reinforced plastic, or sheet metal, and an articulated rod mechanism of, e.g., rods and hinge inserts of springs and stop fittings, due to low material costs. 
     Still other objects and advantages of the present invention will in part be obvious and will in part be apparent from the specification. 
     The present invention accordingly comprises the features of construction, combination of elements, and arrangement of parts, all as exemplified in the constructions herein set forth, and the scope of the invention will be indicated in the claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention is explained in greater detail below with reference to the accompanying drawings directed to one exemplary embodiment in which. 
         FIG. 1  depicts a vehicle with two rear spoiler devices according to an embodiment of the present invention; 
         FIG. 2  is a top view of the lateral rear region of the vehicle on approach to a ramp; 
         FIG. 3  shows a hinge structure from  FIG. 2 ; 
         FIGS. 4-9  illustrate the folding or retraction process of the rear spoiler device according to  FIG. 1  on approach to the ramp; and 
         FIG. 9  depicts the lateral rear region in the retracted or folded stowed position for loading the vehicle. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     A utility vehicle  1  can, e.g., be a truck or a trailer (goods vehicle trailer).  FIG. 1  shows the rear region of the utility vehicle  1  with wheels  2 , a vehicle frame (superstructure)  3  and side wails  4 . The side walls  4  can be solid, e.g., in a box trailer made of metal, or formed, e.g., by tarpaulins carried by the structural parts of the vehicle frame  3 . 
     An access opening  6  for the loading space of the utility vehicle  1  is provided on the rear  5 , and is closed by a roller shutter  7 , which can be retracted vertically upwards. The roller shutter  7  consists of several elements  7 - 1  overlapping in the manner of slats. Thus, the access opening  6  of the utility vehicle  1  is not closed by rear doors swinging laterally rearwards. Instead of the roller shutter  7 , another closure device can be provided that does not open towards the rear, in particular, a closure that opens vertically upwards or inwards such as, e.g., a retractable tarpaulin of flexible material. It is relevant that no swinging room to the rear is required in order to open the closure device  7 . 
     The utility vehicle  1  can therefore reverse close to an unloading station, e.g., a ramp  8  shown in  FIG. 2  or a seal to the ramp, for unloading, so that the driver or a user can then open the roller shutter  7  or the other closure device, e.g., manually or by electric operation. 
     Two lateral rear spoiler devices  10  are arranged in the rear region of the utility vehicle  1  and are fixed directly or indirectly to the vehicle frame  3 . If the side walls  4  are formed rigidly and attached to the vehicle frame, fixing to the side walls  4  is also possible. 
     Each of the lateral rear spoiler devices  10  has an air guiding element  12 , which in the extended or travel position (drive position) in  FIGS. 1 and 2  extends the area of the side walls  4  towards the back and, thus, extends further to the back from the rear  5 . The air guiding element  12  is, e.g., bent (curved) inward and, advantageously, extends over the entire height of the side walls  4 ; it can be made of lightweight material such as plastic or from sheet metal. The length of the air guiding element  12  towards the rear is in principle freely configurable and not limited. The aerodynamic curvature of the air guiding element  12  is known; in particular, a direct breakaway edge at the lateral rear region or at the transition of the side walls  4  to the rear  5  is avoided. 
     The rear spoiler devices  10  can be moved automatically between the travel position shown in  FIGS. 1 and 2  and the stowed position shown in  FIG. 9  by contact on a rear object, in particular, the ramp  8 . For this, they are spring-preloaded in the travel position in  FIGS. 1 and 2 , as will be explained in more detail below. 
     Between the two lateral rear spoiler devices  10 , in the upper region of the rear  5 . e.g., an upper middle rear spoiler device  11  can be provided, which is preferably not moved. The upper middle rear spoiler device, here, shown in the travel position, transforms substantially, for example, into the lateral rear spoiler devices  10  in order to form a rear spoiler arrangement that is closed at both sides and at the top. 
     Each of the rear spoiler devices  10  can have, in addition to the air guiding element  12 , a shift mechanism  14 , which guarantees the movability and elastic preload of the air guiding element  12  in relation to the rear  5 . According to the embodiment shown, the shift mechanism  14  is formed by three vertically spaced, articulated rod mechanisms  15 . In  FIG. 1 , this formation is shown on the left rear spoiler device  10 , Each articulated rod mechanism  15  has two rods (braces)  16 ,  17  and three hinges  18 ,  19 ,  20 . 
     The first rod  16  is attached to the rear  5  at the first hinge  18 , preferably, to the vehicle frame  3  or the end of the side wall  5 . Thus, the first hinge  18  serves also as a fixing device for the entire rear spoiler device  10  on the rear  5  or the vehicle frame  3  in the region of the rear  5 . The second hinge  19  connects the rods  16  and  17 , of which the second rod  17  is shorter than the first rod  16 , e.g., half as long or even shorter. The third hinge  20  connects the air guiding element  12  with the second rod  17 . The hinges  18 ,  19 ,  20 , as indicated by arrows in  FIG. 2 , are preloaded in the opened spring position shown. The spring force consequently acts along the arrow direction to enlarge the angle. Thus, the first rod  16  is pressed rearward away from the side wail or rear, the second rod  17  is pressed into a rearward pointing position and the air guiding element  12  is, in turn, preloaded by springs, such that with its front end  12   a , it terminates approximately flush or level with the side wall  4 . As shown, the air guiding element  12  can protrude slightly laterally so that it lies on the side wall  4  under spring preload. The rear end  12   b  of the air guiding element  12  protrudes freely to the rear. 
     The hinges  18 ,  19 ,  20  furthermore have stops so that the angular positions shown in  FIGS. 1 and 2  are maintained. The stops can be formed by additional components or by the configuration of the rods  16 ,  17  themselves.  FIG. 3  shows such an arrangement as an example for the hinge  19 , which can be transferred accordingly to hinges  18  and  20 . The hinge  19 —also shown alone on the left—has a spring for opening the angle between the rods  16  and  17 . The spring  22  is, preferably, formed as a leg spring, here with two legs, wherein, due to the spring effect of the spring  22 , the stops  36   b  and  17   a  of rods  16  and  17  are pressed against each other. These stops  16   b  and  17   a  can be parts of the rods  16  or  17  or additional components attached to the rods  16 ,  17 , together with the spring  22  as a hinge  19 . 
     Thus, a stop on the vehicle frame  3  is provided at the hinge  18 ; correspondingly at hinge  20  there is a stop on the air guiding element  12 , or the frame  3  and the air guiding element  12  themselves serve as a corresponding stop. 
     The hinges  18 ,  19 ,  20  are thus preloaded in the travel position shown in  FIGS. 1 and 2  and defined by stops. 
     As evident, e.g., from the view in  FIG. 2 , an angle of less than 180° to the inside or to the center line of the vehicle is formed between the rods  16  and  17 . The hinge  19  also lies laterally further out than the hinge  20 , and the hinge  20  lies laterally further out than the front end  12   b  of the air guiding element  12 . This ensures that, on contact, and, hence, on pressure loading on the end  12   b  of the air guiding element  12 , the folding process described according to  FIGS. 3 to 9  below can take place automatically, 
     When the utility vehicle  1  reverses up to the ramp  8 , the air guiding element  12  with its end  12   b  or an end region makes contact with the ramp  8 , which here, e.g., has a rubber buffer surrounding it on three sides in the usual manner. According to  FIG. 4 , the contact point  24  is generally formed between the end  12   b  and the hinge  20 , i.e., on the outside of the air guiding element  12 . The ramp  8  thus exerts a forward-acting force F on the air guiding element  12  at the contact point  24 , wherein this contact point  24  can then generally change since, according to  FIGS. 4 to 9 , the air guiding element  12  swivels in and thus brings its curved outside into different contact points against the spoiler  8 . The force F with the corresponding lever arm therefore exerts a torque on the hinges  20 ,  19 ,  18 , which acts against the spring effect of the respective springs  22 . 
     The further folding process takes place depending on the resulting lever arms and spring strengths of the three springs  22  of the hinges  18 ,  19  and  20 . The hinge mechanism  15  here folds in so that the angles between the rod  16  and the frame  3 , and between the two rods  16  and  17 , become smaller and hence the hinge  20  in which the air guiding element  12  is held comes closer to the frame  3 . The air guiding element  12  can roll or slide slightly on the ramp  8 , so that the angle between the rod  17  and the air guiding element  12  can, e.g., initially become larger, as evident from  FIGS. 4 ,  5  and  6 , and then reduce again on further reversing according to  FIGS. 7 ,  8  and  9 . 
     For this, the spring strength of the hinge  20  is, e.g., designed slightly weaker than the spring strengths of hinges  18  and  19 , where applicable, taking into account the lever arms, so that, on reversing approach according to  FIGS. 4 ,  5 ,  6 , first the air guiding element  12  comes to rest against the ramp  8  and the contact point  24  lies, e.g., substantially close to the hinge  20 . Then, the rods  16 ,  17  fold in further, in the folded state, i.e., in the stowed position in  FIG. 9 , the air guiding element  12  with its rear end  12   b  now extends laterally approximately as far as the frame  3  or the hinge  18 , so that the air guiding element  12   b  does not hinder or significantly restrict access to the access opening  6  after the raising of the roller shutter  7 . Thus, the length of the first rod  16  substantially corresponds to the sum of the lengths of the second rod  17  and the portion of the air guiding element  12  between the hinge  20  and its end  12   b , as evident from  FIG. 9 . 
     If the automatic folding process is hindered or problematical because of the configuration of the ramp  8 , this folding process can also be initiated manually by a user, by pressing in the air guiding element  12  in the region of its front end  12   b.    
     In principle, a lock for the rear spoiler device  10  in the stowed position in  FIG. 9  can be provided. If the rear spoiler device  10  is pressed in by hand, it can therefore be fixed by such a lock. The lock can, e.g., be formed by an additional rod between the hinges  18  and  20 . In principle, however, such a lock is not required. 
     The air guiding element  12  can also be multipiece, i.e., divided into horizontal sections, so that each of the parts is carried by a corresponding rod mechanism  15 . The one-piece design is, however, advantageous so that, on reversing approach to the ramp  18 , the entire air guiding element  12  is folded in with only one contact point  24 . 
     After loading the utility vehicle  1 , the roller shutter  7  can be closed again and the utility vehicle  1  can drive ahead so that the rear spoiler device  10  automatically unfolds again according to the process in  FIG. 9 , back to the travel position of  FIGS. 1 and 2 . 
     Instead of the articulated rod mechanism  15  of two rods  16  and  18 , the air guiding element  12  can, e.g., be made of super-elastic material with suitable forming, i.e., a substantially curved development corresponding to the rods  16 ,  17 . The hinges  18  and  20  can therefore be omitted. 
     It will thus be seen that the objects set forth above, among those made apparent from the preceding description, are efficiently attained, and since certain changes may be made without departing from the spirit and scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense. 
     It is also to be understood that the following claims are intended to cover ail of the generic and specific features of the invention herein described and all statements of the scope of the invention that, as a matter of language, might be said to fall therebetween.