Abstract:
The invention relates to a motor vehicle with a control device (accelerator pedal  11 ), which is to be actuated by an operator and has an at least indirect influence on the torque, the acceleration or the fuel delivery rate of an engine, wherein the control device can be actuated against the force of at least one return means ( 16, 18 ). According to the invention a return means ( 18 ) having an adjustable force is provided.

Description:
STATEMENT OF RELATED APPLICATIONS 
       [0001]    This application is the U.S. National Phase Under Chapter II of the Patent Cooperation Treaty (PCT) of PCT International Application No. PCT/EP2007/007672 having an International Filing Date of 3 Sep. 2007, which claims priority on German Patent Application No. 10 2006 042 497.2 having a filing date of 7 Sep. 2006. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    1. Technical Field 
         [0003]    The invention relates to a motor vehicle with a control device, which is to be actuated by an operator and has an at least indirect influence on the torque, the acceleration or the fuel delivery rate of an engine, wherein the control device can be actuated against the force of at least one return means. The invention further relates to an accessory for a motor vehicle with an accelerator pedal. The accessory may also be a foot mat with return means. 
         [0004]    2. Related Art 
         [0005]    As a control device automobiles have an accelerator pedal, which is operated by the driver with the foot against the action of a return force. Other vehicles may have similar control devices to be actuated by an operator. 
         [0006]    The energy consumption for powering the vehicle varies at least indirectly as a function of the extent to which the control device is actuated or the movement of the accelerator pedal. The further this is depressed towards the floor pan of the vehicle, the more energy is expended in order to power the vehicle. 
         [0007]    A mode of driving in which the accelerator pedal is not actuated right down to the limit stop for driving off or acceleration is especially economic, particularly in the case of high-capacity internal combustion engines. Higher engine speeds with unfavorable specific energy consumption and increased tire wear are thereby avoided. High-performance engines sometimes tempt the driver, even in urban driving, to exceed the admissible top speed when accelerating. This can also occur due to fleeting carelessness. 
         [0008]    The driver can avoid the aforementioned disadvantages if he concentrates on the operation of the control device or accelerator pedal, for example in conjunction with observance of the fuel consumption indicator. This is irksome and also not always feasible, since driving in traffic normally demands the driver&#39;s full attention. 
       BRIEF SUMMARY OF THE INVENTION 
       [0009]    The present invention is intended to provide the operator with an aid to limiting the energy consumption when actuating the control device. 
         [0010]    The motor vehicle according to the invention is characterized by a return means having an adjustable force. The control device or accelerator pedal is usually moved by the operator against the return force of the return means. Basically the control device should be easily actuated, in order to make operation easier for the driver. According to the invention the return force of the return means is now adjustable, in order to temporarily oppose the force applied by the operator with a greater force. Given a higher return force, the operator will spontaneously avoid heavier actuation of the control device and will thus automatically achieve a lower energy consumption when accelerating. The adjustment of the return force should preferably be undertaken by the operator himself. 
         [0011]    The adjustable return means is advantageously provided in addition to a further return means. An accelerator pedal of a motor vehicle usually has a return spring, which in this case is regarded as a further return means. The adjustable return means is then provided in addition. The return forces of the adjustable return means and the further return means are cumulative. 
         [0012]    According to a further idea of the invention the adjustable return means only comes into effect once the control device has overcome a certain travel or angle against the return force of the further return means. This means that initially only the return force of the further return means is operative. Only after more extensive actuation of the control device does the return force of the adjustable return means supervene. As a result the operator is given the impression of a sudden increment in the return force when accelerating. The adjustable return means is capable of varying this sudden force increment or even reducing it to zero, so that only the return force of the further return means is operative. The sudden force increment that occurs indicates to the operator that the actuation of the control device might be economically appropriate only up to this point. Alternatively or in addition, the location of the sudden force increment along the actuating travel of the control device is preferably adjustable via the adjustable return means. 
         [0013]    An actuating device to be actuated by the operator for adjusting the adjustable return means is advantageously provided. The operator thus has full control over the working of the adjustable return means and can adjust this to his individual requirements. 
         [0014]    According to a further idea of the invention the adjustable return means contains a volume of fluid, in particular a compressible volume of gas. This is preferably air. The volume of gas acts as a spring countering the actuation of the control device. The pressure of the volume of fluid, in particular the volume of gas in the adjustable return means, is preferably adjustable. Alternatively or in addition the volume may be increased by inflation or admission of the fluid or may, if necessary, be discharged. 
         [0015]    According to a further idea of the invention the adjustable return means or a volume connected thereto has a pressure-relief valve. On attainment of a specific pressure in the volume of gas, the pressure-relief valve opens, thereby preventing any further increase in the return force. This facilitates operation of the control device in extreme situations, as is the case when sharp acceleration suddenly becomes necessary. 
         [0016]    The adjustable return means advantageously contains a fluid reservoir with flexible, in particular elastic walls, that is to say elastic in the direction of the walls themselves. The control device acts on at least one of the walls. The effective return force varies as a function of the fluid pressure, in particular the gas pressure and/or the deformation of the walls of the reservoir. The reservoir is preferably of the cushion or balloon type and made, in particular, from latex, rubber or rubber-like material or from a woven fabric with a fluid-tight, in particular a gas-tight finish, similar to the cuff of a sphygmomanometer. 
         [0017]    The return force may be generated by the fluid, for example by a compressible gas, in particular air. The gas reservoir may then have inelastic walls. The return force results from the compression of the gas. Where a liquid is used, the walls of the fluid reservoir are preferably elastic. The return force then results from the elastic dilation of the reservoir walls. However, a gas reservoir may also have elastically dilatable walls. 
         [0018]    According to a further idea of the invention the adjustable return means is a fluid-filled cushion, which is of at least double-walled design, that is to say formed with an inner casing and an outer casing. This affords increased safety against incursive influences of all kinds. In this case the inner casing may have elastically dilatable walls and the outer casing may have non-dilatable walls. Elastically dilatable and at the same time fluid-tight material may be susceptible to the effect of sharp-pointed objects, corners, edges etc. The outer casing is made from material that is by comparison more robust, for example from the material used for truck tarpaulins, and thus effectively protects the elastic inner casing. 
         [0019]    According to a further idea of the invention the adjustable return means is connected via a line to a fluid source, in particular a gas source. The latter is preferably an air pump, which acts as actuating device for the adjustable return means. A rubber ball like that in a sphygmomanometer with cuff, for example, is provided as air pump. 
         [0020]    According to a further idea of the invention the adjustable return means or a volume connected thereto has a pressure display. The pressure display is preferably arranged on the actuating device. The pressure display may be a pressure gauge or a more simple display for the operator. 
         [0021]    According to a further idea of the invention the adjustable return means or a volume connected thereto has an actuatable outlet valve. The pressure of the volume of gas can be controlled by the outlet valve or reduced in a very brief time, in particular by the operator. 
         [0022]    According to a further idea of the invention the fluid source may be located on the return means or may be incorporated into the latter. This avoids the need for a longer line between the fluid source and the return means. 
         [0023]    A remote control, in particular a radio or cable remote control, is advantageously provided for the fluid source. A radio connection is possible, for example, via Bluetooth or another short-range radio system. An infrared connection is also possible. The fluid source then preferably has a remotely controlled valve or pump. 
         [0024]    According to a further idea of the invention an air pump is arranged on the return means as fluid source or is incorporated into the return means, particularly with an electrical drive and preferably with a radio receiver for receiving signals for the activation of the air pump drive. An energy storage device for the electrical drive, in particular batteries or accumulators, may likewise be located on the return means. In this case a remote control by radio, cable or other means is also possible. The energy storage device may also be located at a distance from the fluid source or the return means. The electrical energy is then transmitted by cable to the drive. A cable remote control is also possible. The energy storage device may then be provided either in the remote control, on the return means or elsewhere. 
         [0025]    The invention described above can also be provided as an accessory for a motor vehicle with an accelerator pedal. The accessory then comprises at least one return means for the accelerator pedal, a return force of the return means being adjustable. The accessory is intended particularly for retrofitting to the motor vehicle. 
         [0026]    Fasteners and retainers are advantageously provided for locating the return means in a space behind the accelerator pedal, preferably on the accelerator pedal. In particular the retainers are designed in such a way that it is possible to fix the return means between the accelerator pedal and the floor pan or adjoining wall of the motor vehicle. It is also feasible to attach the return means to the accelerator pedal, to the floor pan or to another footwell wall. 
         [0027]    The invention also relates to an accessory for a motor vehicle with an accelerator pedal, having the following features:
       a) fasteners or retainers for locating the accessory in the footwell of the motor vehicle, in particular between the accelerator pedal and the footwell wall or the floor pan.   b) a return means for the accelerator pedal, the return means being provided in addition to a return means that is ordinarily associated with the accelerator pedal anyway.       
 
         [0030]    A return force of the return means operative over a part of the actuating travel of the accelerator pedal is advantageously adjustable. In addition the invention may be combined as an accessory with all features and configurations according to the invention that have previously been specified and are specified below. 
         [0031]    The return means with or without remote control or other constituent parts can also be incorporated into a foot mat or fixedly or detachably connected to the latter. The invention accordingly also relates to a return means associated with a foot mat and a foot mat having such return means. 
         [0032]    The return means associated with the foot mat is advantageously elastically deformable by the pressure of the accelerator pedal. In particular the return means contains a cushion, such as an air cushion, filled with a fluid. The return means may naturally also have the features and functions specified above. Associating the return means with the foot mat avoids any additional fixing of the return means to the accelerator pedal or another site in the footwell of the motor vehicle. All that is required is a precise positioning of the foot mat. In modern vehicles, however, this is ensured by fixing points for the foot mat. Alternatively or in addition the foot mat according to the invention may comprise its own fasteners, for example Velcro strips, adhesive tapes or clips, for securing a defined position in the footwell. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWING FIGURES 
         [0033]    Further features of the invention are set forth in the claims and elsewhere in the description. Advantageous exemplary embodiments of the invention are explained in more detail below with reference to the drawings, in which: 
           [0034]      FIG. 1  shows a schematic representation of a footwell in a motor vehicle with an accelerator pedal and floor pan and return means, 
           [0035]      FIG. 2  shows a representation similar to  FIG. 1 , but with another embodiment of a return means, 
           [0036]      FIG. 3  shows a travel-force diagram to explain the sudden force increment due to the return means, 
           [0037]      FIG. 4  shows a top view of a cushion-like return means, 
           [0038]      FIG. 5  shows a cross section through the cushion according to  FIG. 4  along the line A-A, 
           [0039]      FIG. 6  shows a cross section similar to  FIG. 5 , in a different embodiment, 
           [0040]      FIG. 7   a  shows a schematic drawing of a return means with remote control, 
           [0041]      FIG. 7   b  shows a representation similar to  FIG. 7   a , of another embodiment, 
           [0042]      FIG. 7   c  shows a representation similar to  FIG. 7   a , of a further embodiment, 
           [0043]      FIG. 8  shows a top view of a foot mat with return means, 
           [0044]      FIG. 9  shows a top view of another embodiment of a foot mat with return means. 
       
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
       [0045]    An accelerator pedal  1  as control device is swivel mounted about a lower pivot point  12  in the footwell  10  of a motor vehicle  10 . The swivel movement of the accelerator pedal  11  initiated by a driver as operator is represented by the arrow  13 . 
         [0046]    The pivot point  12  is situated on a floor pan  14 . A wedge-shaped gap, in which the accelerator pedal  11  can be moved to and fro, is formed between the accelerator pedal  11  and a footwell wall  15 , adjoining the floor pan  14  and oriented obliquely upwards. When the accelerator pedal  11  is moved in the direction of the arrow  13 , that is to say towards the footwell wall  15 , the driver must overcome the return force of a return means  16 , which takes the form of a compression spring, for example. 
         [0047]    A stop  17 , towards which the accelerator pedal  11  is maximally moveable, is arranged on the footwell wall  15 , so that even when the accelerator pedal  11  is fully depressed a residual gap remains between the accelerator pedal  11  and the footwell wall  15 . 
         [0048]    An adjustable return means  18 , which is here embodied as a cushion-shaped compressed air accumulator, is arranged in the gap between the accelerator pedal and the footwell wall  15  in addition to the return means  16 . The adjustable return means  18  is preferably attached either to the footwell wall  15  or to the accelerator pedal  11 . The attachment is not shown in the drawings. For example, the return means  18  is connected to the footwell wall  15  by a Velcro strip connection (not shown). A corresponding Velcro tape may be bonded onto the footwell wall  15 . The return means  18  then has a corresponding Velcro tape. The adjustable return means  18  may also be attached to the accelerator pedal  11 , for example by a strap, a Velcro tape, hooks, clips and the like, which are not shown. 
         [0049]    The dimension of the adjustable return means  18  parallel to the direction of the arrow  13  here also varies as a function of the pressure and is preferably always less than the maximum distance of the accelerator pedal  11  from the footwell wall  15 . As a result, the adjustable return means  18  only comes into effect once the accelerator pedal  11  has been moved by a certain travel or angle from the starting position shown in the drawings. 
         [0050]    The adjustable return means  18  is connected by a pressure line  19  to an actuating device  20  to be actuated by the driver. In the present example this is embodied as an air pump in the nature of a rubber ball, as in a sphygmomanometer. Actuation of the rubber ball causes air to be pumped into the adjustable return means  18 , where it increases the internal pressure and thereby increases the return force exerted by this on the accelerator pedal  11 . 
         [0051]    For this purpose a fitting  21  with an outlet valve  22  and an actuating element  23  is assigned to the actuating device  20 . Also connected to the fitting  21  is a pressure display instrument  24 , such as a pointer pressure gauge. 
         [0052]    The actuating device  20  may be located in the interior of the vehicle at a point easily accessible and visible to the driver, for example at or on a center console or between the center console and the driver&#39;s seat or close to a gearshift lever. The pressure line  19  is configured and laid accordingly. 
         [0053]    By actuating the device  20  and the actuating element  23  the driver can individually set the pressure in the adjustable return means and/or the effective thickness thereof and adjust them to the traffic conditions, for example. 
         [0054]    A pressure relief valve  25  is here also assigned to the adjustable return means  18 . This valve prevents a destructive excess pressure in the adjustable return means  18  even under strong actuation of the accelerator pedal  11  and at the same time limits the effective return force. 
         [0055]    The stop  17  prevents the adjustable return means  18  being excessively compressed by the accelerator pedal  11 . 
         [0056]    The means for transmitting the accelerator pedal movement to an engine control system of the motor vehicle are not shown in the drawings. These means are known and do not require further explanation. For example, a lever mechanism or linkage may be provided. 
         [0057]      FIG. 3  shows the aggregate return force occurring in the actuation of the accelerator pedal  11 . Over an initial travel or angle or section only the return force  26  of the return means  16  is operative. As soon as the accelerator pedal  11  is moved somewhat further, that is to say beyond a threshold  27 , the return force of the adjustable return element  18  takes additional effect. This causes a resulting return force  28 . At the threshold  27  a sudden force increment occurs, which is clearly perceived by the driver in the actuation of the accelerator pedal  11  and which, depending on the magnitude of the sudden force increment, can lead to the accelerator pedal  11  being actuated only as far as the threshold  27 . 
         [0058]    The lengths of travel of the two sections before and after the sudden force increment are divided over the total possible movement of the accelerator pedal  11  in a ratio of 1/3 to 2/3, 1/2 to 1/2 or 2/3 to 1/3, for example. Other travel ratios are possible and can easily be configured and even adjusted through corresponding configuration of the return means  18 . The first section may also have a zero length. 
         [0059]    With the outlet valve  22  opened, the return force of the adjustable return means  18  is minimal and even equal to zero. The resulting return force  28  is then equal to the return force of the return means  16 , so that no sudden force increment occurs at the threshold  27 . 
         [0060]      FIG. 2  shows an alternative embodiment of the return means  18 , that is to say a piston-cylinder arrangement with a piston  29  that can be extended from a cylinder  30 . The cylinder  30  is here fixed on the footwell wall  15 , so that the piston  29  can be extended counter to the direction of the arrow  13 . Inversely it is also possible to attach the cylinder  30  to the accelerator pedal  11  or to transpose the cylinder and the piston. 
         [0061]    The pressure line  19  is connected to the cylinder  30 . In addition the cylinder  30  has the pressure-relief valve  25 . A stop corresponding to the stop  17  in  FIG. 1  is not necessary here, since the working of the cylinder  30  and the piston  29  already affords a stop for the accelerator pedal  11 . 
         [0062]    In the fully extended position of the piston  29 , as shown in  FIG. 2 , there is a distinct space between it and the accelerator pedal  11  (in its zero position). On actuation of the accelerator pedal  11  it is initially only necessary to overcome the return force of the return means  16 . Only on reaching the piston  29  does this also act as (adjustable) return means. However, the space is not obligatory. 
         [0063]    The cylinder  30  is preferably attached to the footwell wall  15 , by bolting, welding, riveting or adhesive bonding. 
         [0064]    A return spring may be integrated into the piston-cylinder arrangement, so that the already extended position of the piston varies and can be adjusted as a function of the gas pressure. An embodiment without a spring is also possible, which means that the piston, even under a slight pressure, always assumes the same limit position, at which the sudden force increment is also perceptible to the driver. 
         [0065]    The adjustable return means  18  may also be held on the underside of the accelerator pedal  11 . This alternative is represented by dashed lines in  FIG. 1 . The return means  18  in this embodiment is a cushion or balloon, which is held by a fastener, that is in this case by a band or tape  31  drawn over the accelerator pedal  11 . 
         [0066]    In the simplest embodiment the return means  18  is not adjustable and merely supplements return means  16  that is ordinarily associated with the accelerator pedal  11  anyway. This then results, over a first part of the actuating travel of the accelerator pedal, in a return force deriving solely from the return means  16 . Only over a succeeding part of the actuating travel of the accelerator pedal  11  is the return means  18  additionally operative. Where the return means  18  is not adjustable, the succeeding actuation travels and the point of the sudden force increment will vary solely as a function of the thickness of the return means  18  and the space that exists between the accelerator pedal  11  and the floor pan  14  or footwell wall  15 . 
         [0067]    According to  FIGS. 4 to 6  the cushion-like return means  18  is of special, double-walled design. An outer casing  32  is formed by folding along a fold line  33  and a substantially U-shaped fin seam  34 . The outer casing is composed of a material that is as resistant as possible to mechanical stresses, friction and sharp objects, such as the material used for truck tarpaulins, which is a tear-resistant woven fabric with waterproof coating. An adhesive bond or weld may be provided in the area of the fin seam  34 . 
         [0068]    An inner casing  35 , which serves as fluid accumulator and is here composed of an elastically dilatable material, such as rubber, latex or the like, is arranged inside the outer rectangular casing  32 . For reasons of clarity, connections or lines for the delivery of a fluid into the inner casing  35  are not drawn in  FIGS. 4 to 6 . 
         [0069]    The dimensions and volumes of the outer casing  32  and the inner casing  35  are matched to one another so that a fluid flowing into the inner casing  35  here produces a greater thickness of the return means  18  and a higher return force. According to  FIG. 5  the inner casing  35  is distinctly smaller than the outer casing  32 . This allows the inner casing  35  to expand significantly inside the outer casing  32  and with full pressure exerted on the accelerator pedal, for example, to yield almost completely to the reduction of the thickness. 
         [0070]    In the embodiment in  FIG. 6  the inner casing  35  is folded once. As a result more dilatable wall material is available, so that the elastic wall of the inner casing  35  experiences a lower expansion stress overall. 
         [0071]    On its upper side the cushion-shaped return means  18  has the tape  31  for attachment to the accelerator pedal. The tape  31  may be a rubber band, an elastic fabric band, a Velcro strip or the like. Alternatively clips or hooks may also be provided for attachment to the accelerator pedal. 
         [0072]    The action and working of the cushion-like return means  18  also depend on the ratio between the size of the return means and the size of the accelerator pedal. A return means  18  protruding laterally or at the end of the accelerator pedal allows a residual volume in the return means  18  outside the range of action of the accelerator pedal. A virtually full depression of the accelerator pedal can thus be achieved more easily despite the presence of the return means  18 . 
         [0073]      FIGS. 7   a  to  7   c  show the return means  18  as an air cushion with integral electrical air pump  36 , the drive motor  37  for this, the pressure gauge  38  and the remote control  39 . Widely varying combinations are possible here.  FIGS. 7   a  to  7   c  show only three selected exemplary embodiments: 
         [0074]    According to  FIG. 7   a  the return means  18  and the remote control  39  are coupled together via a radio connection  40  drawn in dashed lines. 
         [0075]    In the exemplary embodiment in  FIG. 7   a  the pressure gauge  38 , the air pump  36 , the electric motor  37  and accumulators  41  are combined into one functional unit  42 , which is arranged immediately next to the return means  18 , for example at the side of it. 
         [0076]    An integral part of the functional unit  42  in this case is a transmitter and receiver unit  43 , which is in wireless communication with a corresponding transmitter and receiver unit  44  of the remote control  39 . 
         [0077]    The remote control  39  has a display  45  and operating elements  46 , for example, pushbuttons. Any accumulators or batteries present are not drawn in. 
         [0078]    The remote control  39  controls the drive of the motor  37  for the air pump  36  and possibly an outlet valve (not shown) in the functional unit  42 . Operating states of the motor  37 , the filling level of the accumulators  41  and/or the pressure determined by the pressure gauge  38  may be displayed on the display  45 , depending on the equipment and range of functions. 
         [0079]    In an especially simple embodiment the unit  44  is embodied only as a transmitter unit and the unit  43  solely as a receiver unit. A pressure gauge is then not required. 
         [0080]    In the embodiment according to  FIG. 7   b  the remote control  39  and the functional unit  42  of the return means  18  are connected together by an electrical cable. This is preferably just a data cable  47 , so that the transmitter and receiver units  43 ,  44  are not needed. Otherwise it largely conforms to the exemplary embodiment in  FIG. 7   a.    
         [0081]      FIG. 7   c  shows a modification of the cable-connected exemplary embodiment. The cable between the functional unit  42  and the remote control  39  is here embodied as a combined power and data cable  48 . As energy-storage device for powering the motor  37 , the accumulators  41  are integrated not into the functional unit  42  but into the remote control  39 . 
         [0082]    The functional unit  42  may be designed separately from the return means  18  and may be held in the footwell of the vehicle. There is then at least one air line between the air pump  36  and the return means  18  (not shown). As an extension of this idea, the functional unit  42  may also be part of the remote control  39  with a correspondingly longer air line. 
         [0083]    The operating elements  46  may be designed, for example, so that at the press of a button previously defined and stored values are set. Alternatively or in addition, selected operating elements may have the functions “increase pressure” and/or “reduce pressure”. 
         [0084]    In an embodiment not shown similar to that in  FIG. 7   a , the function of the remote control  39  is assumed by a mobile phone with Bluetooth facility or by another unit with Bluetooth facility arranged in the vehicle. 
         [0085]    In the embodiment in  FIGS. 8 and 9  the return means  18  is connected to a foot mat  49  or is incorporated into the latter. A foot mat in front of the driver&#39;s seat usually has a recess  50  for the accelerator pedal, at any rate where the accelerator pedal is pivoted at its lower end. This embodiment is shown in  FIG. 8 . 
         [0086]    The return device  18  is located in the area of one edge  51  of the recess  50  and at the same time only a short distance from the upper edge  52  of the foot mat. The return means  18  is preferably bonded, stitched, welded or otherwise connected laterally to the foot mat  49 , depending on the type of materials used. At the same time the return means may be embodied as previously explained with reference to  FIGS. 1 to 7   c  or embodied in some other way. The important thing is that the return means exerts a return force in opposition to the pressure exerted on the accelerator pedal by the driver. The return force may be variable according to the height and/or the location or it may be constant. 
         [0087]    According to  FIG. 9  the foot mat  49  has no recess in the top right-hand corner. This configuration is possible in the case of an accelerator pedal pivoted outside the area of the foot mat (for example at the top). The return means  18  is then located on the top right-hand side of the foot mat or is incorporated into this, so that with correct positioning of the foot mat the return means comes to lie under the accelerator pedal. 
         [0088]    The other elements and components associated with the return means  18 , in particular the parts of the functional unit represented in  FIGS. 7   a  to  7   c  (reference numerals  36 ,  37 ,  38 ,  41 ,  43 ), can also be incorporated into the foot mat  40  or connected thereto. 
         [0089]    The design of the foot mat  49  and the arrangement of the return means  18  against or on the foot mat depend on the spatial proportions of the footwell in the particular vehicle and must be adapted accordingly. The same applies to an instance in which the accelerator pedal is arranged on the left-hand side of the footwell rather than the right-hand side. 
       LIST OF REFERENCE NUMERALS 
       [0000]    
       
           10  footwell 
           11  accelerator pedal 
           12  pivot point 
           13  arrow 
           14  floor pan 
           15  footwell wall 
           16  return means 
           17  stop 
           18  adjustable return means 
           19  pressure line 
           20  actuating device 
           21  fitting 
           22  outlet valve 
           23  actuating element 
           24  pressure display 
           25  pressure-relief valve 
           26  return force 
           27  threshold 
           28  resulting return force 
           29  piston 
           30  cylinder 
           31  tape 
           32  outer casing 
           33  fold line 
           34  fin seam 
           35  inner casing 
           36  air pump 
           37  electric motor 
           38  pressure gauge 
           39  remote control 
           40  radio connection 
           41  accumulators 
           42  functional unit 
           43  transmitter and receiver unit 
           44  transmitter and receiver unit 
           45  display 
           46  operating elements 
           47  data cable 
           48  power and data cable 
           49  foot mat 
           50  recess 
           51  edge of recess 
           52  top edge