Abstract:
An adjustable pedal apparatus for a motor vehicle is provided. The apparatus includes a pedal that can be translated in a longitudinal fashion parallel to the vehicle floor. The pedal is translated by use of a screw that is threadedly attached to the pedal and also pivotally attached to a motion linkage. The position and movement of the motion linkage is uniform irrespective of the longitudinal position of the pedal. The pedal includes a pivot pin that is received by a slot formed in a body structure; translation of the pedal along screw causes longitudinal movement of the pivot pin the said slot. The pivot pin is free to translate within said slot while the pedal is not depressed, when the pedal is depressed the pivot pin becomes fixed longitudinally by a camming formation and locking element arrangement. This allows depression of the pedal to cause the pedal to pivot about the pivot pin.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    1. Technical Field  
           [0002]    The present invention relates in general to motor vehicle pedals. More particularly, but without restriction to the particular embodiment and/or use which is shown and described for purposes of illustration, the present invention relates to pedal systems that provide for adjustment of the brake, clutch, or accelerator pedal relative to a vehicle driver.  
           [0003]    2. Discussion  
           [0004]    In a conventional automobile, pedals are provided for controlling the acceleration and braking functions of the vehicle. If the vehicle includes a manual transmission, a clutch pedal is typically provided. In most motor vehicles today, the pedals have fixed locations. Typically, these pedals are fixed to the body of the vehicle at a point, so that the pedal will pivot about the fixed point when foot pressure is applied by the operator. In order to accommodate driver&#39;s of varying physiques, the driver&#39;s seat is, generally, slidingly engaged to the vehicle such that a driver can position himself or herself relative to either the steering wheel or the pedals. This adjustment provides, to a certain degree, an improvement of driver comfort.  
           [0005]    However, it is nearly impossible to such a single adjustment to accommodate all possible variances in human physiques. In particular, the proportional relation between the lengths of a driver&#39;s arms and legs in relation to the driver&#39;s overall torso size cannot be accommodated through a single adjustment. For example, many smaller people have small legs. Therefore, when they drive a motor vehicle, they must position the seat in its foremost position to properly reach the pedals. Unfortunately, their arms and torso are s typically too close to the steering wheel of the vehicle to be comfortable. Accordingly, it has been widely recognized that some type of pedal adjustment is desirable to provide optimal comfort to the driver while he or she is operating the vehicle.  
           [0006]    Many approaches to providing adjustable pedals have been suggested in the prior art. The most common approach is to provide some type of pushrod, ratcheting, or camming device so that the pedal will operate in a different pivotal range. By utilizing such a device, the static position of the pedal can be modified in the forward and rearward direction. An example of this approach is provided in U.S. Pat. No. 5,771,752, issued Jun. 30, 1998. Although, in general, this type of system works satisfactorily in providing an adjustable pedal, the distance of the pedal to the floor will change as the pedal is pivoted. This may be not desirable because it changes the angle at which foot pressure needs to be applied, and may affect the angle at which the master cylinder pushrod for a brake pedal is activated.  
           [0007]    Many other adjustable pedal systems have been developed in the recent years that provide a linear movement of the pedals so as to maintain the relationship between the pedal and floor. A few examples of such applications can be found in U.S. Pat. No. 4,870,871, issued Oct. 3, 1989, U.S. Pat. No. 5,722,302, issued Mar. 3, 1998, and U.S. Pat. No. 5,010,782, issued Apr. 30, 1991. Although prior art devices such as those described above have proven to be successful, there is a need to develop a system that can be implemented on a vehicle currently in production while, effective, robust, and compact enough to be used in future vehicle development efforts. The present invention also represents substantial improvements over the pedal design disclosed in the aforementioned patents.  
         SUMMARY OF THE INVENTION  
         [0008]    Accordingly, it is a principal objective of the present invention to provide a truly versatile and effective adjustable pedal apparatus for use in a motor vehicle.  
           [0009]    It is another objective of the present invention to provide an adjustable pedal apparatus that can mimic the action of a standard pedal to the master cylinder pushrod while being linearly adjustable in the longitudinal direction.  
           [0010]    It is still another objective of the present invention to provide an adjustable pedal apparatus that includes structure to lock the pivot pin of the pedal in position only while the pedal is depressed.  
           [0011]    It is a further objective of the present invention to provide an adjustable pedal apparatus that can be utilized in an existing vehicle with minimal modification, while effective, robust, and compact enough to be utilized in future vehicle development efforts.  
           [0012]    In one form, the present invention provides an adjustable pedal apparatus for a motor vehicle. The apparatus includes a pedal having a pivot pin disposed near the top end thereof and a footpad disposed near the bottom end thereof. The pedal can be translated in a longitudinal manner parallel to the floor of the motor vehicle. The apparatus also includes a body structure that is attached to the body or chassis of the motor vehicle. The body structure includes a first and second longitudinally extending slots, the first being elevated from the second. The elevated first slot is adapted to receive the pivot pin and to allow for movement of said pivot pin within said first slot. The body structure also has a motion linkage pivotally connected thereto. The pivoting of the motion linkage is designed to mimic the swing of a non-adjustable brake pedal. A tie rod is pivotally attached to the motion linkage and pivotally attached to an attaching unit that is disposed about a screw. The screw extends from the attaching unit and is pivotally and threadedly attached to the pedal via a threaded unit. The attaching unit is received by the second longitudinally extending slot in the body structure. Attaching unit is fixed in position by flanges disposed on the screw. Attaching unit includes a bore of a diameter greater than that of the screw, such that the screw is allowed to rotate freely therein. The pushrod controlling the desired vehicle function is attached to either the tie rod or the motion linkage. This will provide uniform motion for the pushrod when the pedal is depressed irrespective of the longitudinal location of the pedal. A motor is attached to the screw to cause movement of the pedal about the screw. As the screw is translated rearward the attaching unit contacts an abutment formed by the second slot and forces the threaded pedal attachment to translate the pedal rearward. Accordingly, the pivot pin in the first slot translates rearward therewith. As the screw is translated forward the pushrod keeps the attaching unit substantially in place while the pedal, including the pivot pin in the first slot, is translated forward. When the pedal is in the static or non-depressed position the pivot pin is free to translate within the first slot. As soon as the pedal is depressed the pivot pin is locked in place. This is accomplished by a cam, locking mechanism, and spring arrangement. A series of teeth are disposed on the body structure above the first slot, and a lever having mating teeth is pivotally attached to the pedal. The lever is biased towards the pedal by interconnecting the pivot pin and the lever by a spring element. The spring element ensures contact between the teeth on the body structure and the mating teeth on the lever while the pedal is depressed. When the pedal is not depressed, i.e. the static position, a cam formation on the top portion of the pedal contacts the lever. The cam formation acts against the biasing force of the spring to disengage the two sets of teeth, thereby allowing the pivot pint to translate freely within the first slot. It can be appreciated that longitudinal movement of the pedal is designed to occur only when the pedal is in the static position.  
           [0013]    Additional benefits and advantages of the present invention will become apparent to those skilled in the art to which this invention relates from a reading of the subsequent description of the preferred embodiment and the appended claims, taken in conjunction with the accompanying drawings.  
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0014]    [0014]FIG. 1 is a side view of a motor vehicle;  
         [0015]    [0015]FIG. 2 is a perspective view of the adjustable pedal apparatus;  
         [0016]    [0016]FIG. 3 is a side view of the adjustable pedal apparatus illustrating the s pedal in the full forward location and in the static or non-depressed position;  
         [0017]    [0017]FIG. 4 is a side view of is a side view of the adjustable pedal apparatus illustrating the pedal in the full forward location and in the fully depressed position;  
         [0018]    [0018]FIG. 5 is a side view of the adjustable pedal apparatus illustrating the pedal in an intermediate location and in the static position;  
         [0019]    [0019]FIG. 6 is a side view of the adjustable pedal apparatus illustrating the pedal in an intermediate location and in the fully depressed position;  
         [0020]    [0020]FIG. 7 is a side view of the adjustable pedal apparatus illustrating the pedal in the full rearward location and in the static or position; and  
         [0021]    [0021]FIG. 8 is a side view of the adjustable pedal apparatus illustrating the pedal in the full rearward location and in the fully depressed position.  
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0022]    Referring now to the drawings, there is depicted an adjustable pedal apparatus illustrating the preferred embodiment of the present invention. Turning first to FIG. 1, a motor vehicle  10  is shown. Vehicle  10  includes a driver&#39;s seat  12  slidingly engaged to the floor  14  of vehicle  10 . Vehicle  10  also includes a steering vehicle  16  extending from an instrument panel  18 . Disposed below instrument panel  18  and above floor  14  is an adjustable pedal apparatus  20 . Apparatus  20  includes a pedal  22  having a foot pad  24  on the bottom end  25  thereof. In the preferred embodiment, pedal  22  operates the braking functions of the vehicle. It should be appreciated that the teachings of this invention can be utilized on acceleration and clutch pedals as well as brake pedals.  
         [0023]    Turning to FIG. 2, a perspective view of apparatus  20  is illustrated. Apparatus  20  includes a body structure  26  that is attached to vehicle  10 , preferably by bolts. Body structure  26  has a base formation  28  with two opposing walls  30  and  30 ′ projecting therefrom. Each wall  30  and  30 ′ includes a first longitudinally extending slot  32  and  32 ′. Wall  30  further includes a second longitudinally extending slot  34  disposed vertically below first slot  32 .  
         [0024]    Pedal  22  is formed such that it has two upwardly extended arms  36  and  36 ′. The span of arms  36  and  36 ′ is slightly less than the distance between opposing walls  30  and  30 ′. Each arm  36  and  36 ′ terminates in a cam formation  38  and  38 ′. The cam formations  38  and  38 ′ are curved in a way to effectively reduce the height of the top edge of the arm  36  and  36 ′ as the pedal  22  is pivoted by depression thereof. Each arm  36  and  36 ′ also includes a pivot pin  40  and  40 ′ near the top end  41  thereof. Pivot pins  40  and  40 ′ are, preferably, cylindrical projections from arms  36  and  36 ′ and adapted to be received within first slots  32  and  32 ′. It should be appreciated that the diameter of the pivots pins  40  and  40 ′ is just slightly less than the height of the first slot  32  and  32 ′.  
         [0025]    Body structure  26  includes a flange  42  extending from the base formation  28  thereof. Pivotally attached to flange  42  at hinge  43  are a pair of motion linkages  44  and  44 ′. Motion linkages  44  and  44 ′ are attached to flange  42  at their top end and extend downward and terminate around a pivotal attachment to a tie rod  46 . Tie rod  46  extends laterally, as well as rearwardly in some locales, and terminates on one end in a pivotal attachment to an attaching unit  48 . Attaching unit  48  is adapted to receive a translational structure or screw  50 . Screw  50  includes two circular flanges  49  and  51  extending therefrom. Flanges  49  and  51  lock attaching unit  48  in place along screw  50 . Screw  50  extends forward from attaching unit  48  to a pivotal attachment to arm  36  of pedal  22 . Screw  50  extends through threaded unit  47 , threaded unit  47  is pivotally attached to pedal  22 . As screw  50  is rotated, pedal  22  will translate thereon due to the threaded attachment. Therefore, as screw  50  is rotated in a first direction, pedal  22  is translated rearward; and as screw  50  is rotated in a second direction, pedal  22  is translated forward. It should be appreciated that the translation of pedal about screw can be achieved in a variety of different ways. For example, the attaching unit  48  can be threaded and the threaded unit  47  can include a bearing race instead of being threaded. Furthermore, screw  50  may be replaced by any structure that allows translation thereon. Moreover, the screw  50  or translation structure does not need to be motorized, as long as there is some means of translating the units upon the translation structure. Another embodiment may include a threaded attachment in both the attaching unit and the threaded unit that is utilized with a screw having portions threaded in one direction and portions threaded in the other direction, whereby rotation of the screw would cause the units to translate towards each other or to translate away from each other.  
         [0026]    [0026]FIG. 3 illustrates apparatus  20  with pedal  22  in the full forward location. Pedal  22  is non-depressed or static position, in other words, no pressure is placed on foot pad  24  of pedal  22  that would depress the pedal and activate the vehicle function controlled by pedal  22 . With pedal  22  in its full forward position, pivot pin  40  is disposed at the forwardmost end of first slot  32 .  
         [0027]    This position of pivot pin  40  will stay constant even when foot pressure is placed on foot pad  24  to depress pedal  22 . When pedal  22  begins to be depressed, cam formation  38  effectively lowers lever  52 . Lever  52  is v-shaped and pivotally attached to pedal  22  one its lower prong  54 . Preferably, lever  52  is s pivotally attached to pivot pin  40 . The upper prong  56  includes a locking element  58  disposed on the lower surface thereof. Locking element  58  is formed by teeth  60 . The top surface  62  of body structure  26  has a locking element  64  disposed above first slot  32  and extending substantially the length of slot  32 . Locking element  58  is adapted to mate with locking element  64  to ensure the position of pivot pin  40  when pedal  22  is depressed. A biasing element  66  urges contact between locking element  64  and its mating locking element  58 . When the pedal  22  is in the static or non-depressed position, the cam formation  38  acts against biasing element  66  to interrupt the contact between locking elements  58  and  64 , as illustrated in FIG. 3. As the pedal is depressed, cam formation  38  effectively lowers so that biasing element  66  can establish cooperation between locking elements  58  and  64  so as to secure the longitudinal position of pivot pin  40  within first slot  32 , as illustrated in FIG. 4. Biasing element  66  is comprised of a spring  68  interconnecting upper prong  56  of lever  52  and pedal  22 . Spring  68 , preferably, attaches to pedal  22  at pivot pin  40 .  
         [0028]    [0028]FIG. 4 illustrates pedal  22  in the full forward location with foot pressure  70  applied to foot pad  24 . Pedal  22  is termed fully depressed in this illustration. As the pedal  22  is depressed from its static position, FIG. 3, cam formation  38  effectively lowers so that biasing element  66  can establish cooperation between locking elements  58  and  64  so as to secure the longitudinally position of pivot pin  40 . The vertical position of pivot pin  40  is secured by slot  32 . Therefore, the only movement available is pivoting of pedal  22  about pivot pin  40 . The depression of pedal  22  also causes the attaching unit  48 , due to its link with pedal  22  by screw  50 , to move rearward within second slot  34 . In the static position, attaching unit  48  is located against abutment  72  of second slot  34 . During depression of pedal  22 , attaching unit  48  travels until it contacts rear abutment  74  of second slot  34 . It can be appreciated that the length of second slot  34  effectively establishes the maximum amount of throw for pedal  22 . It should as be appreciated that as pedal  22  is depressed, threaded unit  47  pivots about its attachment to pedal  22 . During pedal  22  depression, motion linkages  44  pivot about hinge  43  formed with flange  42 . This motion is attributed to tie rod  46  linking attaching unit  48  and motion linkages  44 . A pushrod  45  (shown in FIG. 2) is preferably pivotally attached to either tie rod  46  or to motion linkages  44 . Force from the motion linkages  44  or tie rod  46  upon the pushrod  45  will activate the braking functions of vehicle  10  in the preferred embodiment. It should be appreciated that the motion linkages  44  and tie rod  66  move in a consistent manner during depression of pedal  22 , irrespective of the location of pedal  22 . It should also be appreciated that the motion linkages  44  effectively mimic the motion of a nonadjustable vehicle pedal. Due to the inherent nature of a brake pushrod  45  that is typically attached directly or indirectly to the master cylinder of the brake system, force is constantly provided from the brake system that encourages the pushrod  45  and thus pedal  22  to return to its static position. It should also be appreciated that a similar return force is available for an accelerator or clutch pedal, thus offering similar function of pedal  22 .  
         [0029]    Turning now to FIG. 5 and its relation to FIG. 3, the translation of pedal  22  from a full forward location to an intermediate location is provided. When the pedal  22  is in the full forward location, it can be translated to an intermediate location by activation of screw  50 . It should be appreciated that the present invention can create numerous intermediate locations between the full forward and full rearward locations. In the preferred embodiment, the screw  50  can be activated by a small electric motor or even manually. As screw  50  is rotated, threaded unit  47  is transitioned along screw  50 . It can be appreciated that any means to translate threaded unit  47  along screw  50  would not deviate from the scope of the present invention. As threaded unit  47  is translated along screw  50 , pedal  22  is translated therewith. As pedal  22  is forced rearward, pivot pin  40  slides rearward within first slot  32 . It can be appreciated that precise tolerances are required for rearward movement of pedal  22  while retaining its axial orientation. It should also be appreciated that by pivotally attaching screw  50  to pedal  22  near its center also contributes to the ability of pedal  22  to maintain its axial orientation while moving rearward. It can further be appreciated that locking elements  58  and  64  are not engaged during the rearward movement of pedal  22 . The engagement of locking elements  58  and  64  may hinder the forward or rearward movement of pedal  22 . In fact, one can develop ways to electronically limit translation of threaded unit  47  along screw  50  when the pedal is depressed.  
         [0030]    To aid in retaining the axial orientation of pedal  22  during translation, spring  80  is provided. Preferably, spring  80  attaches to a fixed projection  82  on the pedal and screw  50  to provide a force directed in a upward and backward direction, as indicated by arrow  83 . This provides an added force to compel the top portion of the pedal  22  to translate consistent with the portion of the pedal  22  that is attached to the screw to insure retention of the axial orientation.  
         [0031]    While in the intermediate location, the pedal can now be depressed as illustrated in FIG. 6. The depression of pedal  22  occurs in the same manner as outlined while the pedal  22  was in the full forward location. The only appreciable difference is that pedal  22  is now closer to attaching unit  48  and motion linkages  44 .  
         [0032]    [0032]FIG. 7 illustrates pedal  22  in its static position in its full rearward location. FIG. 8 illustrates pedal  22  in its fully depressed position in its full rearward location. The full rearward location is achieved from an intermediate position in a manner similar to that previously described when moving from the full forward position to an intermediate position. When transitioning between the full rearward location to an intermediate location, screw  50  is rotated in the opposite direction to cause threaded unit  47  to translate along screw in a direction away from attaching unit  48 . Actual movement of attaching unit  48  is limited by the return force placed on the tie rod  46  or motion linkages  44  from the pushrod. This return force is sufficient enough to maintain attaching unit  48  against abutment  72  thereby causing pedal  22  to move forward.  
         [0033]    While the above description constitutes the preferred embodiment of the invention, it will be appreciated that the invention is susceptible to modification, variation, and change without departing from the proper scope or fair meaning of the accompanying claims.