Abstract:
A device allowing a seated user to use his or her foot to control a member for actuating a system such as a motor vehicle brake boosting system, including a pedal articulated about an axis to a support that can be adjusted in terms of translation in the direction away from or closer to the user&#39;s seat. The pedal cooperates, via a sliding sleeve, with a rod which is itself articulated via levers to a carrying structure. The rod and the levers between them, and together with the pedal, constitute deformable parallelograms whatever the adjustment adopted for the axis of articulation of the pedal to its support, with respect to the carrying structure. The pivoting movement of the pedal is transmitted via one of the levers to a connecting rod which provides a link with the actuating member. Application particularly to adjusting the position of the pedal box of a motor vehicle, in terms of its distance from the driver&#39;s seat.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a device for allowing a seated user to use his or her foot to control a member for actuating a system such as a motor vehicle brake boosting system, said device including a pedal located facing a seat for the user and articulated about an approximately horizontal first axis perpendicular to a direction joining the pedal to the seat, on a support that is mounted adjustably on a carrying structure which also carries the system and the seat, so as to allow the position of the first axis to be adjusted in terms of its distance from the seat, and a linkage connecting the pedal and the actuating member which linkage is articulated about axes parallel to the first axis so as to translate a pivoting movement of the pedal about the first axis with respect to the support into a corresponding displacement of the actuating member with respect to the system and into actuation of this system. 
     Although it may relate to any type of foot control, on any type of machine, by a seated user, it finds a particular application in the control of the boosted braking of a motor vehicle. 
     This is because it is known that the quest for optimum ergonomics in terms of the driving position of a motor vehicle, for reasons of comfort and safety, has led to the provision of possibilities for adapting the dimensional characteristics of the driving position to suit the build of the driver. 
     This adaptation is usually restricted to adjusting the position of the seat, with respect to the floor of the vehicle, in the lengthwise direction thereof, and possibly to adjusting the seat in a heightwise direction, and to adjusting the position of the steering wheel in one and/or other of these two directions, in addition to adjustments regarding the actual configuration of the seat itself. 
     2. Description of the Prior Art 
     However, it has recently been proposed that these possibilities for adaptation be supplemented by a means of adjusting the position of the pedal box, particularly the position of the brake pedal, in the lengthwise direction of the vehicle. 
     To this end, a device of the type mentioned in the preamble in which the support on which the pedal is articulated is itself articulated to a carrying structure, in practical terms to an element of the bodywork or of the chassis of the vehicle has been proposed, so that adjustment is achieved by pivoting the support. 
     This solution has the double disadvantage of the adjustment of the pedal in the lengthwise direction of the vehicle being accompanied by a variation in the level and orientation of the pedal with respect to the floor of said vehicle and of offering only a very restricted adjustment travel if the aforementioned drawback is not to have too pronounced, that is to say too troublesome, an effect. 
     SUMMARY OF THE INVENTION 
     The object of the present invention is to propose a device which overcomes these drawbacks, it being understood that even though this device has been more specifically designed for controlling a member for actuating a motor vehicle brake boosting system, it can be applied to any foot control, by a seated user, of a member for actuating any system. 
     To this end, the present invention proposes a device for allowing a seated user to use his or her foot to control a member for actuating a system such as a motor vehicle brake boosting system, the device including a pedal located facing a seat for the user and articulated about an approximately horizontal first axis perpendicular to a direction joining the pedal to the seat, on a support that is mounted adjustably on a carrying structure which also carries the system and the seat, so as to allow the position of the first axis to be adjusted in terms of its distance from the seat, and a linkage connecting the pedal and the actuating member, which linkage is articulated about axes parallel to the first axis so as to translate a pivoting movement of the pedal about the first axis with respect to the support into a corresponding displacement of the actuating member with respect to the system and into actuation of this system, 
     wherein the support is mounted on the carrying structure so that it can be adjusted in terms of translation in said direction so that the first axis can be placed in several positions, in a determined plane, between two extreme positions which are respectively the position closest to and the position furthest away from the seat, while remaining perpendicular to said direction, and wherein said linkage includes: 
     a first lever articulated to the carrying structure about a second axis located in said plane, between the extreme position closest to the seat and the latter, parallel to the first axis and having a free end, 
     a second lever articulated to the carrying structure about a third axis located in said plane, further from the seat than the extreme position furthest from the latter, parallel to the first axis and having a free end, 
     a straight rod articulated to the free ends of the first and second levers respectively at a fourth axis and a fifth axis, the fourth and fifth axes being parallel to the first axis, spaced apart by a distance that is the same as the distance separating the second and third axes from each other and the distance separating the fourth and second axes from each other being identical to the distance separating the fifth and third axes from each other so that the rod and the first and second levers define a deformable parallelogram with the carrying structure, 
     a sleeve mounted so that it can slide along the rod and articulated to the pedal about a sixth axis parallel to the first axis and spaced from the latter by a distance that is equal to the distance separating the fourth and second axes from each other or separating the fifth and third axes from each other, and 
     a connecting rod providing a link between one of the first and second levers and the actuating member, articulated to said lever about a seventh axis parallel to the first axis and offset respectively with respect to the second or third axis. 
     It will be readily understood that, if considering, for example, the application of the device to controlling the boosted braking of a motor vehicle, and once the plane of the first, second and third axes has been carefully oriented with respect to the floor of the vehicle, a device according to the invention allows any amount of adjustment travel, in the lengthwise direction of the vehicle, without any variation in the level and orientation of the pedal with respect to said floor, it being understood that this advantage is had irrespective of the envisaged application. The adjustment travel is in fact limited only by the space available for the device, and may be as much as several tens of centimeters, this allowing it to satisfy all needs. 
     Naturally, it could be anticipated for the seventh axis to coincide with the fourth or fifth axis, but it could also be anticipated for it to be offset with respect to these two axes, in terms of angle and/or in terms of distance from the second or third axis respectively, this making it possible to introduce a change of angle effect and/or a step-up or step-down effect between the pivoting movement of the pedal and the movement transmitted to the actuating member. 
     These two possibilities are compatible with articulating the linking connecting rod, about the seventh axis, on the free end of the first or of the second lever. 
     However, it is also possible to envisage for the first and second levers to be double and have a first respective branch articulated, on the one hand, to the carrying structure about the second or third axis respectively and, on the other hand, to the rod about the fourth or fifth axis respectively, and a second respective branch secured to the first branch at the second or third axis respectively, and having a free end defining an eighth or ninth axis respectively, the eighth and ninth axes being parallel to the first axis, spaced apart by a distance identical to the distance separating the second and third axes from each other and the distance separating the eighth and second axes from each other being identical to the distance separating the ninth and third axes from each other, for a connecting rod providing a coupling between the two levers to be articulated about the eighth and ninth axes to the free ends of the second branches to define a deformable parallelogram with the second branches of said levers and with the carrying structure, and for the connecting rod providing a link to be articulated about the seventh axis to the free end of the second branch of one of the first and second levers. 
     Even if it is desired to establish a change of angle effect and/or a step-up or step-down effect between the pivoting movement of the pedal and the effect applied to the actuating member, it is then possible to envisage for the seventh axis to be coincident with the eighth or ninth axis, respectively, insofar as it is possible to envisage for the eighth and ninth axes to the offset respectively with respect to the fourth and fifth axes. 
     This is because it will be seen that this offset may just as easily be either an offset in terms of respective distance from the second or third axis, or an angular offset about this second or third axis, which may make it easier for the entire device to be installed, according to the space available. 
     The device according to the invention thus offers a broad scope of possibilities for installations and a broad scope of possible uses. 
     It also has the advantage of being compatible with the two conventional methods of mounting articulated pedals, namely the so-called “floor-mounted” approach and the so-called “suspended” method of mounting. If the former of these approaches is to be taken, then provision is made for the fourth, fifth and sixth axes to be located above said plane and for the pedal to have a region acted upon by the user&#39;s foot that is located above the sixth axis and, if the latter of these approaches is to be adopted, provision is made for the fourth, fifth and sixth axes to be located below said plane and for the pedal to have a region acted upon by the user&#39;s foot that is below the sixth axis. 
     When the system controlled using a device according to the invention is a vehicle brake boosting system, it is advantageously anticipated for the support also to carry, articulated about tenth and eleventh axes parallel to the first axis or coincident with it, a throttle pedal and, as appropriate, a clutch pedal. 
     It will be noted that the throttle pedal and any clutch pedal there may be are traditionally connected to the members they control by a funicular transmission, generally by a BOWDEN cable, which does not give rise to the same difficulties, when adjusting the pedals in the lengthwise direction of the vehicle, as the articulated-linkage connection used for transmitting the movement of the brake pedal to the member for actuating the brake boosting system. 
     Naturally, a person skilled in the art will have no difficulty in designing means of adjusting the support in terms of translation with respect to the carrying structure, these means advantageously being produced in the form of remote-adjustment means made available to the user who will thus be able to make the adjustments while occupying a natural usage position, seated in his or her seat. 
    
    
     Other features and advantages of the device according to the invention will emerge from the description hereinbelow which relates to two non-limiting examples, and from the appended drawings which form an integral part of this description. It will be noted that these two examples relate to the control of the member for actuating a motor vehicle brake boosting system, but the person skilled in the art will readily understand that the arrangements described and illustrated can be read across directly to any other type of application. 
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 illustrates, in a diagrammatic perspective view, one example of the mounting of a device according to the invention associated with a brake pedal articulated under the floor of the vehicle. 
     FIG. 2 illustrates, viewed in side elevation to a larger scale than FIG. 1, the details of the cooperation between the pedal and the rod connecting the two levers. 
     FIG. 3 shows the same detail as FIG. 2, in section on a plane perpendicular to the rod, passing through the sixth axis and labeled III—III in FIG.  2 . 
     FIGS. 4 and 5 show a view in side elevation of the assembly illustrated in FIG. 1, respectively in the absence of actuation of the brake pedal and when this pedal is actuated. 
     FIG. 6 illustrates, in a view similar to that of FIG. 1, an example of the mounting of a device according to the invention associated with a brake pedal suspended under the steering column (not illustrated). 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Reference is first of all made to the exemplary application of the invention illustrated in FIGS. 1 to  5 , where  1  is used to denote a brake pedal, standing up from the floor  2  of the vehicle, forward of the driver&#39;s seat  3  when referring to a given direction  4  in which the vehicle is travelling forward, so that it can be acted upon by one of the driver&#39;s feet  5  in the direction that pivots it forward so as to control a backward sliding of a rod  6  constituting the member for actuating a servo-brake  7  located to the rear of the pedal  1 . The rod  6  is mounted so that it can slide in a straight line in the servo-brake  7  along an axis  80  parallel to the direction  4  and has an unsupported actuation free end  78  projecting, forward, from the servo-brake  7  so that action, backward, on this end is translated into a movement whereby the rod  6  penetrates the servo-brake  7  and into a start or increase of braking action, and so that action subsequently applied to this end in a forward direction translates into a movement whereby the rod  6  emerges from the servo-brake  7  and into a reduction or cancellation of the braking action. The notions of forward and backward are understood here, as later, as being with reference to the direction  4  of forward travel of the vehicle. 
     For this purpose, in this example, the pedal  1  is articulated, under the floor  2  through which it passes through a slot  8 , about an axis  9  perpendicular to an unreferenced longitudinal mid-plane of the vehicle, that is to say perpendicular to the direction  4  and horizontal when the vehicle is resting on horizontal ground. This axis  9  is stationary with respect to the floor  2  of the vehicle when the vehicle is in use, but its position in the direction  4  and in the opposite direction can be adjusted with respect to this floor  2 , while at the same time retaining the same scope for the predetermined positioning of the rod  6  in terms of its sliding in the servo-brake  7  for a given inclination of the pedal  1  about the axis  9  with respect to the floor  2 . 
     To do this, the mounting used for the pedal  1  is the one which will now be described. 
     A rigid cradle  10 , for example a parallelepiped cradle, is mounted under the floor  2  so that it is secured to this floor or secured to constituent parts of the vehicle other than the floor  2  but which are secured to this floor, for example bodywork or chassis elements, thus forming an entity that is secured to the bearing structure of the vehicle, also carrying the servo-brake  71  mounted securely, and the seat  3 , which is generally mounted so that it can be adjusted in the direction  4  and in the opposite direction. 
     The cradle  10  includes, in particular, in the example illustrated, a flat top wall  11 , with cutouts to such a point that it is restricted to a surround, running alongside the floor  2  from underneath the latter, parallel to it, and a bottom wall  12  which is itself whole but which is also flat, parallel to the wall  11  and to the floor  2 . It will be seen that as the floor  2  slopes upward slightly towards the front in the example illustrated, the walls  11  and  12  of the cradle  10  do likewise, but this inclination is at a small enough angle that the direction  4  can be retained as the forward-direction point of reference for describing the cradle  10  and the components it carries for applying the present invention. 
     Although it runs directly along the floor  2 , the top wall  11  of the cradle  10  is faced away from this floor  2  by a uniform space  13  which is just deep enough for two slideways  14 ,  15  arranged respectively one on each side of the pedal  1 , to be housed between the wall  11  and the floor  2 , the slideways being mutually parallel and more specifically oriented in a direction  16  parallel to the floor  2  and to the two walls  11  and  12  of the cradle  10  and parallel, like the direction  4 , to the unillustrated longitudinal mid-plane of the vehicle, that is to say perpendicular to the axis  9 . It may be seen that the slot  8  formed in the floor  2  for the passage of the pedal  1  is made in this direction  16 , which joins the pedal  1  to the seat  3  and constitutes the direction in which the device according to the invention allows the position of the axis  9  to be adjusted with respect to the floor  2 , in terms of distance from the seat  3 . 
     The two slideways  14 ,  15  bear, in sliding in the direction  16  on the top wall  11  of the cradle  10  with respect to this top wall  11 , a rigid plate  17  which is thus housed between the top wall  11  of the cradle  10  and the floor  2 , along which it runs, parallel thereto, which plate  17  bears, secured to it inside the cradle  10  through the cut-out  18  in the top wall  11  thereof and above the top wall  12 , a mount  19  forming a bearing  20  of axis  9 . Via this bearing, the mount  19  carries, with the possibility of relative rotation about the axis  9 , an extreme lower region  21  of the pedal  1 , which passes from the bottom upward first of all through the top wall  11  of the cradle  10 , through the cut-out  18  in this top wall  11 , then through the plate  17  via a slot  22  made therein in the direction  16  immediately below the slot  8 , then through the floor  2  via the slot  8 , so that the pedal  1  exhibits, above the floor  2 , a top end region  22  in the shape of a paddle facing rearward, which constitutes the region of the pedal  1  which is acted upon by the driver&#39;s foot  5 . When not acted upon, the pedal  1  occupies an extreme orientation illustrated in FIG. 4, in which it stands up above the floor  2  and the upper end region  22  occupies a rearward extreme position approximately vertically in line with the axis  9 ; this extreme orientation of the pedal  1  and this extreme rearward position of its upper end region  22 , which correspond to the absence of action by the foot  5  on the pedal  1 , also correspond to the absence of a braking action, the rod  6  then emerging from the servo-brake  7  by its maximum amount. If the foot  5  applies a forward action to the upper end region  22  of the pedal  1 , this pedal can be pivoted forward, with the effect of increasingly heavy braking as the rod  6  is progressively driven into the servo-brake  7 , until such time as the pedal  1  is brought into another extreme orientation in which it is illustrated in FIG.  5  and which corresponds to maximum penetration of the rod  6  into the servo-brake  7 , that is to say maximum braking; in this extreme orientation, the pedal  1  is couched forward on the floor  2  and its upper end region  22  occupies a forward extreme position. Naturally, the size of the slot  22  and, given the possibilities offered by the present invention of adjusting the position of the axis  9 , the dimension of the slot  8  in the direction  16  are compatible with this movement of the pedal  1  from one of its extreme orientations to the other regardless of the position of the axis  9  within the limits allowed by the device according to the invention. 
     These extreme orientations of the pedal  1  are defined by stop means which are not illustrated but which are well known in themselves, for example associated with the mount  19  and the pedal  1  is returned from its extreme orientation illustrated in FIG. 5 to its extreme orientation illustrated in FIG. 4 by elastic return means acting, for example, between it and the mount  19 , in a way which is not illustrated but is well known in itself, so that the release of the action applied in the forward direction by the foot  5  to the upper end region  22  of the pedal  1  is accompanied by an automatic return of this pedal to its extreme position illustrated in FIG.  4  and by a reduction followed by a disappearance of the braking effect. 
     It will be readily understood that the position of the axis  9  in the direction  16  inside the cradle  10  is directly related to the position of the plate  17  along the slideways  14  and  15 . 
     In consequence, in order to allow the position of the axis  9  to be adjusted in the direction  16  means are provided for adjusting the position of the plate  17  along the slideways  14  and  15  and for immobilizing the plate  17  with respect to these slideways in any desired position of adjustment, between two limits which correspond, for the axis  9 , to two extreme positions, respectively the forward extreme position illustrated in FIG.  1  and in solid line in FIGS. 4 and 5, and the rear extreme position illustrated in chain line in FIGS. 4 and 5. These two extreme positions, just like the distance d which separates them from each other in the direction parallel to the direction  16 , can be chosen at will when implementing the present invention, within the limits of the space available for the device according to the invention, whose size in the direction  16  they govern. In particular, the distance d or maximum adjustment travel for the axis  9 , may be as much as several tens of centimeters, but a value of the order of 15 to 25 cm, and for example of 18 cm is generally enough in this application, given the possibility of adjusting the position of the seat  3  in the direction  4  and in the opposite direction also; naturally, these figures are, however, mentioned merely by way of non-limiting example. 
     There are various means which may be provided for adjusting the position of the plate  17  along the slideways  14  and  15  but, according to the preferred embodiment illustrated in FIG. 1, these means are electrical, powered by the vehicle battery, and may be controlled remotely from the vehicle instrument panel, for example using a push-button, not depicted, of the type used for operating electric windows, so as to allow the plate  17  to be moved forward or backward at will with respect to the slideways  14  and  15  and so as to allow this movement to be stopped. 
     For this purpose, the top wall  11  of the cradle  10  carries, secured to it right towards the rear, at least partially projecting into the gap  13 , an electric motor  23  which, in the gap  13 , has two outputs with the same axis  24  parallel to the axis  9 , each of these outputs being connected by reduction gearing  25 ,  26 , forming an angle change of 90°, to a respective screw  27 ,  28  of axis  29 ,  30  parallel to the direction  16  and stationary with respect to the cradle  10 , each of these screws  27 ,  28  being immobilized against a movement parallel to the direction  16  or perpendicular to this direction with respect to the cradle  10  but swiveling in a respective bearing  31 ,  32  secured to the top wall  11  of the cradle  10 , inside the gap  13 , and each running along a respective one of the slideways  14  and  15  between these slideways. Each of the screws  27 ,  28  thus extends as far as an unsupported free end  33 ,  34  inside the gap  13  above the top wall  11  of the cradle  10 , passing over the plate  17 . Coaxial with each of the screws  27 ,  28 , this plate  17  carries, secured to it, inside the gap  13 , a respective nut  35 ,  36  engaged with the appropriate screw so that the powering of the electric motor  23  so as to cause its outputs to rotate in either one direction or the other causes, by the rotation of the screws  27  and  28  in the one direction or in the other, a corresponding translational movement of the nuts  35  and  36  of the plate  17  either forward or backward. The design of the electrical power supply to the motor  23 , of the reduction gearing  25  and  26 , of the screws  27  and  28  and of the nuts  35  and  36  used for this is within the normal competence of the person skilled in the art. Likewise, it is within the normal competence of the latter to choose the pitch of the screws  27  and  28  and/or the step-down ratio of the reduction gearing  25  and  26  so that the transmission of movement between the motor  23  and the nuts  35 ,  36  is irreversible under normal conditions of use, that is to say that an appropriate supply of electricity to the motor  23  can cause the desired translation of the nuts  35  and  36  via the screws  27  and  28 , but that a pushing or pulling force applied forward or backward to the plate  17  in the direction  16 , and particularly the effect resulting from the thrust applied forward by the foot  5  to the top end region  22  of the pedal  1  is not able to result in a translation of the plate  17  when the motor  23  is not driven. 
     It may be seen that in addition to the brake pedal  1 , the plate  17  may also carry, articulated about respective axes which are not illustrated and which may be coincident with the axis  9  or offset with respect to said axis while at the same time being parallel to it, an accelerator pedal  37  and, as appropriate, a clutch pedal  38  which pedal(s) may thus be adjusted, together with the brake pedal  1 , in terms of distance from the seat  3 ; each of these pedals  37  and  38  may be mounted on the plate  17  in the way which is conventional, and therefore not illustrated, passing through the floor  2  through a respective slot parallel to the slot  8 , and be connected also in the conventional way, not illustrated, for example by a funicular transmission to a throttle control member and to a clutch control member, respectively. 
     By contrast, means specific to the present invention are provided for connecting the pedal  1  to the rod  6  for actuating the servo-brake  7 , and these means will now be described. 
     Inside the cradle  10 , the bottom wall  12  thereof carries, secured to it, respectively to the rear of the rear extreme position of the axis  9  and to the front of the front extreme position thereof, a respective bearing  39 ,  40  defining a respective axis  41 ,  42  parallel to the axis  9  and located in one and the same plane  43  thereas, this plane  43  being parallel to the direction  16 , perpendicular to the unillustrated longitudinal mid-plane of the vehicle, and located between the top  11  and bottom  12  walls of the cradle  10 , closer to the bottom wall  12  than to the top wall  11 . In all the positions that the axis  9  can occupy from one of its extreme positions to the other, the axes  41  and  42  are located respectively to the rear of and in front of the axis  9 . 
     The two bearings  39  and  40  are located on one same side of the pedal  1 , namely on the opposite side to the mount  19 , with reference to an unreferenced direction defined by the axis  9 , and each of them carries and guides, in rotation about the respective axis  41 ,  42  with respect to the cradle  10 , a respective double lever  44 ,  45 . 
     On that side of the bearings  39  and  40  which faces towards the pedal  1 , between the respective bearing and this pedal, each lever  44 ,  45  has a first straight branch  46 ,  47 , having a first end  48 ,  49  for articulation about the axis  41 ,  42  with respect to the associated bearing  39 ,  40  and a second end  50 ,  51  which is free, articulated to a respective free end  52 ,  53  of a straight rod  54  about a respective axis  55 ,  56  parallel to the axes  9 ,  41 ,  42 . Under normal conditions of use, the rod  54  is arranged above the plane  43 , between this plane and the top wall  11  of the cradle  10 , and lies beside the pedal  1  on the same side thereof as the bearings  39  and  40 , that is to say on the opposite side to the mount  19 . It is oriented in the direction  16  and, for this purpose, between the axes  55  and  56  has a length equal to the distance separating the axes  41  and  42  in the direction  16 , and the distance separating the axis  55  from the axis  41  is identical to the distance separating the axis  56  from the axis  42 . It may be seen that, from the axis  41 ,  42 , respectively, to its free end  50 ,  51 , each branch  46 ,  47  is shorter than the distance separating the plane  43  from the top wall  11  of the cradle  10 , so that, like the rod  54 , the branches  46  and  47  of the levers  44  and  45  are always located under the top wall  11  of the cradle  10 . 
     On the same side as the rod  54 , the pedal  1  carries, between its lower end region  21  and the top wall  11  of the cradle  10  in any orientation of the pedal  1 , from one of its aforementioned extreme orientations to the other, a sleeve  57  which is articulated to the pedal  1  about an axis  58  parallel to the axis  9  and located at a distance therefrom which is identical to the distance separating the axis  55  from the axis  41  or the axis  56  from the axis  42 . The sleeve  57 , free to pivot about the axis  58  with respect to the pedal  1  without any other possibility for relative displacement, is pierced right through, along an axis  59  perpendicular to the axis  58  and offset on the same side as the rod  54  with respect to the pedal  1 , by a bore  60  which is cylindrical of revolution about the axis  59  and carries internally, secured to it, a bushing  61  for sliding engaged coaxially over the rod  54 , so that the axis  59  which is therefore common to it intersects the axes  55  and  56  and so that, by means of the bushing  61 , the sleeve  57  can slide along the rod  54  in the direction  16  when the position of the axis  9  is adjusted in this direction. 
     It may be seen that the rod  54 , articulated about the axes  55  and  56  to the branches  46  and  47  of the levers  44  and  45 , these branches  46  and  47 , articulated about the axes  41  and  42  to the bearings  39  and  40 , and the plane  43  passing through the axes  41  and  42  which are stationary with respect to the cradle  10  constitute a deformable parallelogram articulated about the axes  41 ,  42 ,  55 ,  56 , and that the pedal  1 , articulated to the mount  19  about the axis  9  located in the same plane  43  as the axes  41  and  42  and to the rod  54  about the axis  58  located in an unreferenced plane common to the axes  55  and  56 , defines with the rod  54 , the plane  43  and, respectively, one or other of the lever branches  46 ,  47 , another deformable parallelogram, it being understood that on assembly, care is taken to orientate an unreferenced plane defined by the axes  9  and  58  parallel to unreferenced planes defined respectively by the axes  41  and  55  and by the axes  42  and  46 , each of these unreferenced planes being, in practice, inclined upward at the front in a pronounced way when the pedal  1  occupies the extreme orientation illustrated in FIG. 4, and a less pronounced way when it occupies its extreme orientation illustrated in FIG.  5 . 
     Thus, regardless of the position of the axis  9  between the axes  41  and  42 , as a result of the distance between the pedal  1  and the seat  3  being adjusted, a rotation of the pedal  1  through a determined angle from the extreme orientation illustrated in FIG. 4, by pivoting about the axis  9  with respect to the mount  19 , results in a rotational movement through the same angle, and in the same direction, of the branches  46  and  47  of the levers  44  and  45 , that is to say of these levers  44  and  45  in their entirety. For reasons of geometry which will be readily understood by the person skilled in the art, the sleeve  57  cannot slide along the rod  54  during such pivoting, but on the other hand encounters no difficulty in sliding along the rod  54  when the position between the axis  9  and the seat  3  is being adjusted and this sliding does not in any way affect the deformable parallelogram structure described earlier nor does it lead to a change in orientation of the pedal  1  about its axis  9  or to a change in the level of the end  22  of the pedal  1  with respect to the floor  2  of the vehicle. 
     To allow it to transmit its pivoting movement to the rod  6 , each lever  44 ,  45  has a second straight branch  60 ,  61  located on the opposite side of the respective bearing  39 ,  40  to the branch  46 ,  47 . Each of the branches  60 ,  61  has one end  62 ,  63  for articulation to the bearing  39 ,  40  about the corresponding axis  41 ,  42 , the end  62  being secured to the end  48  of the branch  46 , while the end  63  is secured to the end  49  of the branch  67 , through the bearings  39  and  40 , respectively. Each branch  60 ,  61  also has a free end  64 ,  65  which itself defines a respective axis  66 ,  67  of articulation to a respective free end  68 ,  69  of a straight rod forming a coupling rod  70  parallel to the rod  54  and, like the latter, located between the plane  43  and the top wall  11  of the cradle  10  under normal conditions of use of the device. The distance separating the axes  66  and  67  from each other is identical to the distance separating the axes  41  and  42  from each other or alternatively separating the axes  55  and  56  from each other, and the distance separating the axis  66  from the axis  41  is identical to the distance separating the axis  67  from the axis  42  so that the connecting rod  70 , the branches  60  and  61  of the levers  44 ,  45  and the plane  43  considered as being connected with the cradle  10  also define a deformable parallelogram. The length of the branches  60 ,  61  of the levers  44 ,  45  measured from the respective axis  41 ,  42  is shorter than the distance separating each of these axes from the top wall  11  of the cradle  10 , which means that the connecting rod  70  just like the free ends  64 ,  65  of the branches  60 ,  61  are always located below the top wall  11  of the cradle  10  under normal conditions of use of the device. 
     The orientation of the branches  60 ,  61  of the levers  44 ,  45 , defined, for example, by the orientation of an unreferenced plane passing through the axes  41  and  66  and of an unreferenced plane passing through the axes  42  and  67 , may be different than that of the branches  46  or  47 , or identical to it. In the example illustrated, if reference is made to the extreme orientation of the pedal  1  illustrated in FIG. 4, the branches  60  and  61  slope upward toward the rear with reference to the direction  4  whereas, in the orientation illustrated in FIG. 5, they slope upward toward the front with reference to this direction, although this example is not in any way restrictive. 
     It will be seen that the distance separating the axes  66  and  41  or the axes  67  and  42  may be identical to the distance separating the axes  55  and  41  or the axes  56  and  42  or be different than it, as is the case in the example illustrated in which this distance is greater so that the axes  66  and  67  effect a longer circumferential travel than the axes  55  and  56 , with reference to the axis  41  or  42  respectively, for a pivoting of the pedal  1  through a given angle starting from its extreme orientation illustrated in FIG.  4 . 
     A movement step-up effect or likewise a step-down effect or neutral effect can thus be applied between the pedal  1  and the free ends  64  and  65  of the branches  60  and  61  of the levers  44  and  45 , particularly depending on the installation of the servo-brake  7 , and on a need for matching between the permissible limiting travel of the rod  6  for controlling the servo-brake  7  and the pivoting travel available between the two extreme orientations of the pedal  1 . 
     For this purpose, depending on the installation of the servo-brake  7  in the vehicle, articulated to the free end  65  of the branch  61  of the lever  45  about the axis  67 , and this is not illustrated, or to the free end  64  of the branch  60  of the lever  44  about the axis  66 , and which is illustrated, is a free front end  71  of a straight linking connecting rod  72  which lies approximately as a continuation of the connecting rod  70  which couples the two levers  44  and  45 . The linking connecting rod  72 , thus directed toward the rear from the axis  66  in the example illustrated, also has a free rear end  73  by which it is articulated, about an axis  74  parallel to the axis  66 , to a free lower end  75  of a transmission lever  76  which also has a free upper end  77  in engagement with a free end  78  of the rod  6  of the servo-brake  7 . Between these two free ends  75 ,  77 , the lever  76  is articulated about an axis  79  parallel to the axis  74  on a component, not depicted, secured to the bearing structure of the vehicle and consisting, for example, of part of the bodywork thereof. While all the aforementioned pivoting movements occur about axes which are stationary with respect to the components which are articulated about them, the method of collaboration between the free end  77  of the lever  76  and the free end  78  of the rod  6  is an articulation about an axis  81  parallel to the axes  74  and  79  and coplanar with the latter, stationary with respect to the rod  6  but mobile with respect to the lever  76  in the direction toward or away from the axes  74  and  79  while remaining coplanar with these latter, according to an arrangement known to the person skilled in the art so that a pivoting of the lever  76  about the axis  79  with respect to the bearing structure of the vehicle through an angle that is determined by the angle of pivoting of the pedal  1  from its orientation illustrated in FIG. 4 causes a rectilinear translation of the rod  6  along the axis  80  toward the inside of the servo-brake  7 , without the possibility of relative play along this axis  80  but with a possibility of relative play in an unreferenced direction perpendicular to the axes  74  and  79 , in a way which is readily understandable to a person skilled in the art, in order to take account of the fact that the movement of the lever  76  is a rotational movement and that of the rod  6  is a translational movement. Thus, the travel of the rod  6  along the axis  80  in the direction of penetration into the servo-brake  7  and braking when the pedal  1  is pivoted from its orientation illustrated in FIG. 4 toward its orientation illustrated in FIG. 5, or out of the servo-brake  7 , releasing the braking effect, when the pedal is allowed to return to its orientation illustrated in FIG. 4, occurs with an amplitude that is linked by a one-to-one relationship to the amplitude of the pivoting of the pedal  1 , the position of the rod  6  along the axis  80  with respect to the servo-brake  7  being at every moment representative of the angular position of the pedal  1  about the axis  9 . Naturally, it would not be departing from the scope of the present invention if each lever  44 ,  45  had just one branch  46 ,  47 , that is to say if the second branches  60 ,  61  and the connecting rod  70  coupling them together were omitted and if the linking connecting rod  72  were articulated directly about an axis parallel to the axes  41  and  42 , either directly about the axis  55  on the branch  46  or the axis  56  on the branch  47 , or about an axis offset angularly and/or by a distance, with reference to the axis  41  or  42  respectively, on the branch  46  or the branch  47 , in an arrangement that the person skilled in the art may easily deduce from the exemplary application of the invention which will now be described, with reference to FIG.  6 . 
     This second example corresponds to a so-called “suspended” approach to mounting the pedal box of a motor vehicle, that is to say that the pedals hang down from the steering column, not depicted, instead of standing up from the floor. 
     There are, however, broad similarities between this embodiment and the one described with reference to FIGS. 1 to  5 , which means that the same numerical references will be used to denote identical or similar elements. 
     This example again shows the servo-brake  7 , its actuating rod  6  which can move in terms of translation with respect to it along a rectilinear axis  80 , and the cradle  10 , which, however, is then confined to a single wall similar to the top wall  11  of the cradle  10  described with reference to FIGS. 1 to  5 , and which therefore also has the reference  11 . This wall  11  is fastened securely to the bearing structure of the vehicle, or forms an integral part of this bearing structure, and is arranged under the steering column, not illustrated, perpendicularly to a longitudinal mid-plane, also not illustrated, of the vehicle and more specifically parallel to that region of the floor (the floor is not illustrated) thereof which lies directly forward of the driver&#39;s seat  3 , with reference to a normal direction  4  in which the vehicle is travelling forward. 
     Like the top wall  11  of the cradle  10  described with reference to FIGS. 1 to  5 , the wall  11  forming the cradle  10  in this example has a large cut-out  18  and bears secured to it, on each side of this cut-out  18 , respectively two slideways  14 ,  15  which are identical to those described with reference to FIGS. 1 to  5  and which have a common direction  16  which is parallel both to the floor of the vehicle and to the longitudinal mid-plane thereof. 
     Likewise, the two slideways  14  and  15  serve to guide the translation in the direction  16  with respect to the wall  11  of a plate  17  resting on this wall  11 , and the position of the plate  17  in sliding along the slideways  14 ,  15 , that is to say in the direction  16 , may be controlled by means  23  to  36  which in every respect are identical to those described with reference to FIGS. 1 to  5  and which are arranged, like the latter components, at least for the most part on top of the wall  11 . These means in particular employ an electric motor  23  powered with electricity from the vehicle&#39;s on-board battery and controlled remotely from the vehicle&#39;s instrument panel so as to cause two lead screws  27 ,  28 , which run respectively alongside the slideway  14  and alongside the slideway  15 , between these slideways to rotate in one direction or the other, or to remain stationary, so that these screws cooperate with nuts  35 ,  36  borne securely by the plate  17 , on top thereof. 
     From underneath, the plate  17  bears, secured to it, inside the cut-out  18 , a clevis mount  82  defining, under the wall  11 , an axis  83  perpendicular to the aforementioned longitudinal mid-plane of the vehicle, that is to say perpendicular to the direction  4  and to the direction  16  and horizontal when the vehicle is resting on a horizontal surface. The clevis mount  82  bears, so that it can rotate about the axis  83  with respect to the plate  17 , an upper end region  84  of a brake pedal  85  placed facing the driver&#39;s seat  3  in the direction  16  and also having, at a level lower down than its upper end region  84 , a lower end region  86  constituting its region which is acted upon by the driver&#39;s foot, not depicted. It can be seen that, like the plate  17  described with reference to FIGS. 1 to  5 , the plate  17  of this embodiment may also bear, articulated about axes which are coincident with the axis  83  or parallel thereto, and suspended through the cut-out  18  in the wall  11 , an accelerator pedal  87  and, possibly, a clutch pedal  88 , which are mounted on the plate  17  and connected respectively to a throttle control and to a clutch control by conventional means known to the person skilled in the art and not illustrated. 
     Naturally, the size of the cut-out  18  in the direction  16  is such as to allow the position of the axis  83  to be adjusted in the direction  16  with respect to the cradle  10  and with respect to the entire bearing structure of the vehicle, between two predetermined extreme positions, namely a forward extreme position in which the pedal  85  is illustrated in solid line in FIG. 6, which is the position furthest from the driver&#39;s seat  3 , and a rear extreme position illustrated in chain line in FIG. 6, which is the position closest to the driver&#39;s seat  3 . 
     Between its two extreme regions  84  and  86 , the pedal  85  bears, so that it can rotate about an axis  89  parallel to the axis  83  and located lower down than the latter, a sleeve  90  arranged beside the pedal  85  and having a construction which in every respect is similar to that of the sleeve  57 . In particular, this sleeve  90  is pierced right through with an unreferenced bore of axis  91  perpendicular to the axis  89  and lined with a bushing, not illustrated, in which it receives, with the possibility of relative sliding along the axis  91  without any other possibility of relative displacement, a straight rod  92  arranged under the wall  11 , in every respect similar to the rod  54  and guided, like the latter rod, in such a way as to allow the pedal  85  to pivot forward, about the axis  83 , from an extreme orientation illustrated in solid line in FIG. 6, corresponding to the absence of action by the driver&#39;s foot and the absence of braking, and to a rear extreme position of the lower end region  86 , into an unillustrated extreme orientation which corresponds to maximum braking and in which the lower end region  86  of the pedal  85  occupies a forward extreme position under the effect of action applied by the driver&#39;s foot, with elastic return from the extreme orientation for maximum braking into the extreme orientation for the absence of braking by elastic return means mounted in a way known to a person skilled in the art, while keeping the axis  91 , common to the rod  92  and to the sleeve  90 , parallel to the direction  16 . 
     For this purpose, the rod  92  has a rear free end  93  and a front free end  94  which are articulated, about a respective axis  95 ,  96  parallel to the axis  89  located in one same unreferenced plane as these axes  95  and  96 , on a free lower end  97 ,  98  of a respective lever  99 ,  100  which is also articulated, by an upper end  101 ,  102 , about a respective axis  103 ,  104  parallel to the axis  83  with which the axes  103  and  104  are coplanar just as the axes  41  and  42  are coplanar with the axis  9 , under a respective clevis mount  105 ,  106  fixed securely under the wall  11 , respectively to the rear of the cut-out  18  and at the front thereof, that is to say respectively to the rear of the rear extreme position of the axis  83  and forward of the forward extreme position of the axis  83 , within the limits of sliding of the plate  17  in the direction  16  of the wall  11 . The distance separating the axes  95  and  96  is identical to the distance separating the axes  103  and  104 , just as the distance separating the axes  103  and  93  is identical to the distance separating the axes  104  and  94  and to the distance separating the axes  83  and  89 , which means that the levers  99  and  100 , together with the rod  92  and the wall  11 , or more specifically the plane  113  of the axes  103  and  104  which are stationary with respect to this wall, form a deformable parallelogram articulated about the axes  93 ,  96 ,  103 ,  104 , and so that the pedal  85 , appropriately orientated when mounting in such a way that a plane passing through the axes  89  and  83  is parallel to the planes passing respectively through the axes  95  and  103  and through the axes  96  and  104 , itself forms a deformable parallelogram with the rod  92 , the wall  11  to which the plate  17  is secured once any adjustment has been made, or more specifically the plane  113  containing not only the axes  103  and  104  but also the axis  85 , and each of the levers  99  and  100  respectively. 
     In order to provide a kinematic link between the pedal  86  and the rod  6  of the servo-brake  7 , the lever  99 , and this is not illustrated, or the lever  100 , and this is illustrated, is articulated about an axis  107  parallel to the axis  106  and which may be coincident with the axis  96 , and this is not illustrated, or offset with respect to this axis away from the axis  104  and/or at an angle, as is illustrated, on a free rear end  108  of a straight linking connecting rod  109  extending forward from this free end  108  as far as a second free end or front end  110  articulated about an axis  111  parallel to the axis  109  in a clevis mount  112  secured to the rod  6  of the servo-brake  7 . 
     It will be readily understood that a pivoting of the pedal  85  from its extreme orientation for the absence of action and absence of braking results directly in a thrust applied, via the lever  100 , possibly with a step-up or step-down effect, the linking connecting rod  109  and the clevis mount  112 , to the rod  6  in the direction of a translation toward the inside of the servo-brake  7 , placed forward of this rod  6 , with a translational travel of the rod  6  which is representative of the pivoting travel imparted to the pedal  85 , the sleeve  90  behaving as if it were as one with the rod  92  during pivoting of the pedal  85 . Likewise, the return of this pedal to its position for the absence of action results in the rod  6  re-emerging from the servo-brake  7 , and the configuration is such that at every moment the position of the rod  6  is representative of that of the pedal  86  in terms of orientation about the axis  83  with respect to the plate  17  and with respect to the wall  11 , and that this is the case irrespective of the position of the axis  83  between the front and rear extreme positions obtained by adjusting the position of the plate  17  in the direction  16  with respect to the wall  11 . By contrast, the sleeve  90 , capable of sliding along the rod  92 , does not oppose this adjusting of the position of the axis  83 . 
     In this respect, reference is made to the explanations given with regard to FIGS. 1 to  5 , which can be read across directly to this embodiment. 
     Naturally, the two examples which have just been described are not in any way limiting, and numerous alternative forms may be envisaged without in any way departing from the scope of the present invention. In particular, in the case of the suspended pedal, a double-lever arrangement similar to the one described with reference to FIGS. 1 to  5  could be adopted, each of the levers  99  and  100  being replaced by a double lever similar to the levers  44  and  45 , one branch of which would be connected to the rod  92  and the other branch of which would be connected to a coupling connecting rod which, together with the respective branches of the levers and the plate  11 , would form a deformable parallelogram, the connecting rod  109  then being articulated to that one of the branches of one of the levers which is connected to this coupling connecting rod. 
     Furthermore, depending on the installation of the servo-brake  7 , it would be possible to use a direct connection between the connecting rod  72  and the rod of this servo-brake, with reference to the example illustrated in FIGS. 1 to  5 , in the manner described with reference to FIG. 6, just as it would be possible to provide an indirect connection, similar to what was described with reference to FIGS. 1 to  5 , in a setup which in other respects was similar to the one described with reference to FIG.  6 . 
     Likewise, the device according to the invention could be adapted to areas of application other than that of the control of the braking of a motor vehicle without in any way departing from the scope of the invention.