Control system for adjustable pedal assembly

Information

  • Patent Grant
  • 6810765
  • Patent Number
    6,810,765
  • Date Filed
    Wednesday, December 19, 2001
    23 years ago
  • Date Issued
    Tuesday, November 2, 2004
    20 years ago
Abstract
An adjustable control pedal for a motor vehicle includes a lower arm which moves relative to an upper arm to adjust the position of a pedal. A control system includes a sensor and a controller in communication with the sensor. The controller determines a position of lower arm based on signals from the sensor and automatically stops movement when the lower arm reaches a stored position or an end of travel without engaging mechanical stops, when sensors indicate that there is a failure in the drive system, and when sensors indicate that a predetermined fore/aft offset between two pedals is not maintained. The controller automatically moves the lower arm to a predetermined position when signals indicate the driver may egress the vehicle. A lock-out switch prevents movement of the lower arm so that the lower arm is not accidentally moved.
Description




STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH




Not Applicable




REFERENCE TO MICROFICHE APPENDIX




Not Applicable




FIELD OF THE INVENTION




The present invention generally relates to a control pedal for a motor vehicle and, more particularly, to a control system for selectively adjusting the control pedal to desired positions.




BACKGROUND OF THE INVENTION




Control pedals are typically provided in a motor vehicle, such as an automobile, which are foot operated by the driver. Separate control pedals are provided for operating brakes and an engine throttle. When the motor vehicle has a manual transmission, a third control pedal is provided for operating a transmission clutch. A front seat of the motor vehicle is typically mounted on tracks so that the seat is forwardly and rearwardly adjustable along the tracks to a plurality of positions so that the driver can adjust the front seat to the most advantageous position for working the control pedals.




This adjustment method of moving the front seat along the tracks generally fills the need to accommodate drivers of various size, but it raises several concerns. First, this adjustment method still may not accommodate all drivers due to very wide differences in anatomical dimensions of drivers. Second, the position of the seat may be uncomfortable for some drivers. Therefore, it is desirable to have an additional or alternate adjustment method to accommodate drivers of various size.




Many proposals have been made to selectively adjust the position of the control pedals relative to the steering wheel and the front seat in order to accommodate drivers of various size. For example, U.S. Pat. Nos. 5,632,183, 5,697,260, 5,722,302, 5,819,593, 5,937,707, and 5,964,125, the disclosures of which are expressly incorporated herein in their entirety by reference, each disclose an adjustable control pedal assembly. The control pedal assembly includes a hollow guide tube, a rotatable screw shaft coaxially extending within the guide tube, a nut in threaded engagement with the screw shaft and slidable within the guide tube, and a control pedal rigidly connected to the nut. The control pedal is moved forward and rearward when an electric motor rotates the screw shaft to translate the nut along the screw shaft within the guide tube. A potentiometer is provided at the motor which sends signals to a CPU regarding motor shaft position for determining the position of the nut. While this control pedal assembly may adequately adjust the position of the control pedal to accommodate drivers of various size, this control pedal may be prone to undetected failures. Accordingly, there is a need in the art for an adjustable control pedal assembly which selectively adjusts the position of the pedal to accommodate drivers of various size, is relatively simple and inexpensive to produce, and is highly reliable in operation.




SUMMARY OF THE INVENTION




The present invention provides a control system for an adjustable control pedal which overcomes at least some of the above-noted problems of the related art. According to the present invention, a control pedal includes a first support, a screw secured to the first support, a nut threadably engaging the screw and adapted to move axially along the screw upon rotation of the screw, and a motor operatively connected to the screw to selectively rotate the screw. A second support carries a pedal at a lower end and is operatively connected to the nut for fore-aft movement of the second support relative to the first support upon axial movement of the nut along the screw. A control system includes a sensor located near the screw and adapted to sense rotations of the screw and a controller in communication with the sensor to receive signals from the sensor. With the sensor located near the screw, rotation of the screw can be directly determined from the sensor.




According to another aspect of the present invention, a control includes a first support, a screw secured to the first support, a nut threadably engaging the screw and adapted to move axially along the screw upon rotation of the screw, and a motor operatively connected to the screw to rotate the screw and axially move the nut along the screw in response to rotation of the screw. A second support carries a pedal and is operatively connected to the nut for fore-aft movement of the second support relative to the first support upon axial movement of the nut along the screw. The control pedal also includes a sensor and a controller in communication with the sensor to receive signals from the sensor. The controller is adapted to determine a position of the nut along the screw based on signals from the sensor and to automatically stop the motor when the nut reaches a predetermined end of travel for the nut along the screw. By utilizing electronic or “soft” stops rather than engaging mechanical or “hard” stops at the ends of travel, undesired stress on the motor and premature failure of the motor can be prevented.




According to yet another aspect of the present invention, a control pedal includes a first support, a screw secured to the first support, a nut threadably engaging the screw and adapted to move axially along the screw upon rotation of the screw, and a motor operatively connected to the screw to selectively rotate the screw and axially move the nut along the screw in response to the rotation of the screw. A second support carries a pedal and is operatively connected to the nut for fore-aft movement of the second support relative to the first support upon axial movement of the nut along the screw. The control pedal further includes a sensor and a controller in communication with the sensor to receive signals from the sensor. The controller is adapted to automatically stop the motor when signals from the sensor indicate that the screw is not rotating. An early detection of a failure in the mechanical system allows the pedal assembly to be “shut down” to prevent damage or further damage to the system.




According to even yet another aspect of the present invention, a control pedal assembly includes first and second control pedals Each control pedal includes a first support, a screw secured to the first support, and a nut threadably engaging the screw. Each control pedal also includes a second support carrying a pedal and operatively connected to the nut for fore-aft movement of the second support relative to the first support upon axial movement of the nut along of the screw. A control system includes at least one motor operatively connected to the screws to selectively rotate the screws and axially move the nuts along the screws in response to rotation of the screws, a sensor located near the screw of the first control pedal and adapted to sense rotation of the screw of the first control pedal, and a controller in communication with the sensor to receive signals from the sensor. In one embodiment the screws are connected in series with the motor and the sensor is located near the last screws so that a single sensor is required to indicate failure anywhere along the drive chain. In another embodiment, a second sensor is located at the screw of the second control pedal. This embodiment is particularly advantageous to automatically stop the motor when positions of the nuts indicate that a predetermined fore-aft relationship between the pedals has not been maintained. An example of such a predetermined fore-aft relationship is the rearward positioning of an accelerator pedal relative to a brake pedal which is typically referred to as step over. Early detection of a change in the predetermined relationship between the two control pedals allows the control pedal assembly to be “shut down” to minimize the change in the predetermined relationship between the control pedals.




According to even yet another aspect of the present invention, a control pedal includes a first support, a screw secured to the first support, a nut threadably engaging the screw and adapted to axially move along the screw upon rotation of the screw; and a motor operatively connected to the screw to selectively rotate the screw and axially move the nut along the screw. A second support carries a pedal and is operatively connected to the nut for fore-aft movement of the second support relative to the first support upon axial movement of the nut along the screw. A controller is in communication with the motor and is adapted to automatically operate the motor to move the second support in a forward direction relative to the first support to a predetermined position when predetermined conditions are met. By Automatically moving the control pedal forward when the predetermined conditions indicate the driver is about to egress the motor vehicle, the driver is provided additional leg room to egress the vehicle and the next driver has additional room to ingress the vehicle.




According to even yet another aspect of the present invention, a control pedal assembly includes a first support, a screw secured to the first support, a nut threadably engaging the screw and adapted to axially move along the screw upon rotation of the screw, and a motor operatively connected to the screw to selectively rotate the screw and axially move the nut along the screw. A second support carries a pedal and is operatively connected to the nut for fore-aft movement of the second support relative to the first support upon axial movement of the nut along the screw. A control system includes a lock-out switch adapted to be manually engaged and a controller which operatively connects the lock-out switch and the motor to prevent movement of the second support relative to the first support when the lock-out switch is engaged. The lock-out switch enables the driver to prevent undesired or accidental movement of the control pedal.




From the foregoing disclosure and the following more detailed description of various preferred embodiments it will be apparent to those skilled in the art that the present invention provides a significant advance in the technology and art of control pedal assemblies. Particularly significant in this regard is the potential the invention affords for providing a high quality, feature-rich, low cost assembly. Additional features and advantages of various preferred embodiments will be better understood in view of the detailed description provided below.











BRIEF DESCRIPTION OF THE DRAWINGS




These and further features of the present invention will be apparent with reference to the following description and drawing, wherein:





FIG. 1

is a perspective view of an adjustable control pedal assembly according to the present invention having two control pedals wherein each control pedal has a lower arm selectively movable relative to an upper arm along a horizontal slot provided in the upper arm;





FIG. 2

is a rear elevational view of the adjustable control pedal assembly of

FIG. 1

;





FIG. 3

is a perspective view of the adjustable control pedal assembly of

FIGS. 1 and 2

showing the opposite side of

FIG. 1

;





FIG. 4

is a top plan view of the adjustable control pedal assembly of

FIGS. 1-3

;





FIG. 5A

is an enlarged, fragmented perspective view of a portion of

FIG. 3

showing a drive assembly of one of the control pedals of

FIGS. 1-4

, wherein the view is partially exploded and some components are removed for clarity;





FIG. 5B

is a perspective view of a drive screw attachment of the drive assembly of

FIG. 5A

;





FIG. 6

is an enlarged, fragmented elevational view, in cross section, of the drive assembly of

FIG. 5A

;





FIG. 7

is a schematic view of a control system for the adjustable control pedal assembly of

FIGS. 1-6

; and





FIG. 8

is a control logic diagram for the control system of FIG.


6


.











It should be understood that the appended drawings are not necessarily to scale, presenting a somewhat simplified representation of various preferred features illustrative of the basic principles of the invention. The specific design features of a control pedal assembly as disclosed herein, including, for example, specific dimensions of the upper and lower arms will be determined in part by the particular intended application and use environment. Certain features of the illustrated embodiments have been enlarged or distorted relative to others to facilitate visualization and clear understanding. In particular, thin features may be thickened, for example, for clarity or illustration. All references to direction and position, unless otherwise indicated, refer to the orientation of the control pedal assembly illustrated in the drawings. In general, up or upward refers to an upward direction in the plane of the paper in FIG.


1


and down or downward refers to a down direction in the plane of the paper in FIG.


1


. Also in general, fore or forward refers to a direction toward the front of the motor vehicle and aft or rearward refers to a direction toward the rear of the motor vehicle.




DETAILED DESCRIPTION OF CERTAIN PREFERRED EMBODIMENTS




It will be apparent to those skilled in the art, that is, to those who have knowledge or experience in this area of technology, that many uses and design variations are possible for the improved control pedal assemblies disclosed herein. The following detailed discussion of various alternative and preferred embodiments will illustrate the general principles of the invention with reference to a control pedal assembly for use with a motor vehicle. Other embodiments suitable for other applications will be apparent to those skilled in the art given the benefit of this disclosure. The term “snap-fit connection” is used herein and in the claims to mean a connection between at least two components wherein one of the components has an opening and the other component has a protrusion extending into the opening, and either the protrusion or the opening has a resiliently deformable to allow insertion of the protrusion into the opening as the deformable portion deforms upon entry but to deny undesired withdrawal of the protrusion from the opening after the deformable portion resiliently snaps back such that the two components are secured together.




Referring now to the drawings,

FIGS. 1-6

show a control pedal assembly


10


for a motor vehicle, such as an automobile, according to the present invention which is selectively adjustable to a desired position by a driver. While the illustrated embodiments of the present invention are particularly adapted for use with an automobile, it is noted that the present invention can be utilized with any vehicle having at least one foot operated control pedal including trucks, buses, vans, recreational vehicles, earth moving equipment and the like, off road vehicles such as dune buggies and the like, air borne vehicles, and water borne vehicles.




The control pedal assembly


10


includes first and second control pedals


12




a


,


12




b


and a control system


13


for selectively adjusting the position of the control pedals


12




a


,


12




b


. In the illustrated embodiment, the control pedals


12




a


,


12




b


are adapted as brake and accelerator pedals respectively. While the illustrated control pedal assembly includes two control pedals


12




a


,


12




b


, it is noted that the control pedal assembly can have a single control pedal within the scope of the present invention such as, for example, a single pedal adapted as a clutch, brake or accelerator pedal. It is also noted that the control pedal assembly can have more than two control pedals within the scope of the present invention such as, for example, three pedals adapted as clutch, brake and accelerator pedals respectively.




The control pedals


12




a


,


12




b


are selectively adjustable by the operator in a forward/rearward direction. In multiple pedal embodiments, the control pedals


12




a


,


12




b


are preferably adjusted together simultaneously to maintain desired relationships between the pedals such as, for example, “step over”, that is, the forward position of the accelerator pedal


12




b


relative to the brake pedal


12




a


(best shown in FIG.


4


). It is noted however, that individual adjustment of each control pedal


12




a


,


12




b


is within the scope of the present invention.




Each pedal assembly is generally the same except as shown in

FIGS. 1-6

and as noted herein below. Accordingly, only one control pedal


12




a


will be described in detail. The control pedal


12




a


includes an upper arm


14


, a lower arm


16


, and a drive assembly


18


. The upper arm


14


is sized and shaped for pivotal attachment to a mounting bracket. The mounting bracket is adapted to rigidly attach the adjustable control pedal assembly


10


to a firewall or other rigid structure of the motor vehicle in a known manner. The upper arm


14


is generally an elongate plate oriented in a vertical plane. The illustrated upper arm


14


is generally “L-shaped” having an upper or vertical portion


14




a


which generally vertically extends downward from the mounting bracket and a lower or horizontal portion


14




b


which generally horizontally extends in a rearward direction from a lower end of the upper portion


14




a.






The upper portion


14




a


of the upper arm


14


is adapted for pivotal attachment to the mounting bracket. The illustrated upper arm


14


has an opening


22


formed for cooperation with the mounting bracket and a pivot pin. With the pivot pin extending through the mounting bracket and the opening


22


of and the upper arm


14


, the upper arm


14


is pivotable about a horizontally and laterally extending pivot axis


26


formed by the axis of the pivot pin. The upper arm


14


is operably connected to a control device such as a clutch, brake or throttle such that pivotal movement of the upper arm


14


operates the control device in a desired manner. The upper arm


14


can be connected to the control device by, for example, a push-pull cable for mechanical actuation or electrical wire or cable for electronic signals. The illustrated upper arm


14


is provided with a pin


28


for connection to the control device of a mechanical actuator.




The lower portion


14




b


of the upper arm


14


is adapted for supporting the lower arm


16


and for selected fore and aft movement of the lower arm


16


along the lower portion


14




b


of the upper arm


14


. A horizontally extending slot


32


is formed in the lower portion


14




b


of the upper arm


14


and extends the entire thickness of the plate. The lower portion


14




b


is substantially planar or flat in the area of the slot. The slot


32


is adapted for cooperation with the lower arm


16


as described in more detail hereinbelow. The illustrated upper arm


14


includes an insert


34


forming the slot


32


but it is noted that the slot


32


can be formed solely by the plate of the upper arm


14


. The insert


34


is formed of any suitable low friction and/or high wear resistant material such as, for example, an acetyl resin such as DELRIN. The insert


32


preferably extends along each side of the upper arm


14


around the entire periphery of the slot


32


to form planar laterally facing bearing surfaces


36


,


38


adjacent the slot


32


.




The lower arm


16


is sized and shaped for attachment to the upper arm


14


and selected fore and aft movement along the slot


32


of the upper arm


14


. The lower arm


16


is generally an elongate plate oriented in a vertical plane so that it is generally a downward extension of the upper arm


14


. The lower arm


16


includes a pedal


40


at its lower end and a guide


42


at its upper end. The pedal


40


is adapted for depression by the driver of the motor vehicle to pivot the lower and upper arms


14


,


16


about the pivot axis


26


to obtain a desired control input to the motor vehicle. The guide


42


is sized and shaped for cooperation with the slot


32


of the upper arm


14


. The illustrated guide


42


is a laterally and horizontally extending tab formed by bending the upper end of the lower arm


16


substantially perpendicular to the main body of the lower arm


16


. The guide


42


and the slot


32


are preferably sized to minimize vertical movement of the guide


42


within the slot


32


. It is noted that the guide


42


can take many alternative forms within the scope of the present invention. It is also noted that while the illustrated guide


42


is unitary with the main body of the lower arm


16


, that is of one piece construction, the guide


42


can alternatively be integrally connected to the main body of the lower arm


16


, that is a separate component rigidly secured to the main body of the lower arm


16


.




The guide


42


extends through the slot


32


of the upper arm


14


so that the lower arm


16


is supported by the upper arm


14


by contact of the guide


42


and a bottom bearing surface of the slot


32


and the lower arm


16


is movable fore and aft relative to the upper arm


14


as the guide


42


slides along the bottom bearing surface of the slot


32


. The main body of the lower arm


16


engages the bearing surface


36


adjacent the slot


32


on one side of the upper arm


14


. Upper and lower bearing members


44


,


46


are secured to the free end of the guide


42


on the opposite side of the upper arm


16


and engage the bearing surface


38


adjacent the slot


32


on the other side of the upper arm


14


above and below the slot


32


respectively. The upper and lower bearing members


44


,


46


have a first portion for attachment to the guide


42


and a second portion forming a planar bearing surface


48


for engagement with the bearing surface


38


of the upper arm


14


. The illustrated upper and lower bearing members


44


,


46


are bent plates wherein the first portion is bent substantially perpendicular to the second portion. The lower arm


16


and the upper and lower bearing members


44


,


46


are preferably sized to minimize lateral movement, or “side slash”, of the guide


42


. Assembled in this manner, the guide


42


is held in the slot


32


to secure the lower arm


16


to the upper arm


14


such that the lower arm guide


42


and lower arm


16


are only movable, relative to the upper arm


14


, fore and aft along the slot


32


.




As best shown in

FIGS. 5 and 6

, the drive assembly


18


includes a screw shaft or drive screw


50


, a drive screw housing or attachment


52


for securing the drive assembly


18


to the upper arm


14


, a drive nut


54


adapted for movement along the drive screw


50


in response to rotation of the drive screw


50


, a drive nut mounting bracket or attachment


56


for securing the drive assembly


18


to the lower arm


16


, an electric motor


58


for rotating the drive screw


50


(best shown in FIGS.


1


-


4


), and a drive cable


60


for connecting the motor


58


to the drive screw


50


(best shown in FIGS.


1


-


4


).




The drive screw


50


is an elongate shaft having a central threaded portion


62


adapted for cooperation with the drive nut


54


. The drive screw


50


is preferably formed of resin such as, for example, NYLON but can be alternately formed of a metal such as, for example, steel. The forward end of the drive screw


50


is provided with a bearing surface


66


which cooperates with the drive screw attachment


52


to form a first self-aligning joint


68


, that is, to freely permit pivoting of the drive screw


50


relative to the drive screw attachment


52


and the upper arm


14


about at least axes perpendicular to the drive screw rotational axis


64


. The first self-aligning joint


68


automatically corrects misalignment of the drive screw


50


and/or the drive nut


54


. The illustrated first self aligning joint


68


also forms a snap-fit connection between the drive screw


50


and the drive screw attachment


52


. The illustrated bearing surface


66


is generally frusto-spherically shaped and unitary with the drive screw


50


. It is noted that the bearing surfaces


66


, and thus the first self-aligning joint


68


, can have other forms within the scope of the present invention such as, for example, the embodiment shown in FIG.


8


and described in more detail hereinbelow.




As best shown in

FIGS. 5B and 6

, the drive screw attachment


52


is sized and shaped for supporting the drive screw


50


and attaching the drive screw


50


to the upper arm


14


. The drive screw attachment


52


is preferably molded of a suitable plastic material such as, for example, NYLON but can alternatively be formed of metal such as steel. The drive screw attachment


52


includes a support portion


76


and an attachment portion


78


. The support portion


76


is generally tubular-shaped having open ends. The rearward end of the support portion


76


forms a hollow portion or cavity


80


sized and shaped for cooperating the bearing surface


66


of the drive screw


50


to form the first self-aligning joint


68


. The cavity


80


forms a bearing surface


82


sized and shaped to cooperate with the bearing surfaces


66


of the drive screw


50


. The illustrated bearing surface


82


is a curved groove or race facing the rotational axis


64


. The forward end of the support portion


76


is adapted for connection of the drive cable


60


in a known manner.




The attachment portion


78


of the drive screw attachment


52


is adapted for securing the support portion


76


to the upper arm


14


. The illustrate attachment portion


78


is adapted as a “snap-in connection” having a tubular body


84


laterally extending from the support portion


76


main body, upper and lower tabs


85


extending from the body


84


, and a pair of resiliently deformable fingers


86


carrying abutments


87


. The body


84


is sized and shaped to extend through an opening formed in the upper arm


14


located generally above and forward of the slot


32


. The tabs


85


are sized and shaped to engage the side of the upper arm


14


to limit insertion of the body


84


into the opening of the upper arm


14


. The deformable fingers


86


are sized and shaped so that the fingers


86


are inwardly deflected into the hollow interior of the body


84


as the body


84


is inserted into the opening and resiliently return or spring back upon exiting the opening on the other side of the upper arm


14


. Each deformable finger


86


is preferably provided with an angled camming surface to automatically deflect the finger


86


upon insertion of the body


84


into the opening of the upper arm


14


. The abutments


87


formed by the fingers


86


are each sized and shaped to prevent undesired withdrawal of the body


84


from the opening of the upper arm


14


by creating an interference against withdrawal. To withdraw the body


84


, the fingers


86


are depressed to inwardly move the abutments into the hollow interior of the body


84


and remove the interference.




As best shown in

FIGS. 5A and 6

, the drive nut


54


is adapted for movement along the drive screw


50


in response to rotation of the drive screw


50


. The drive nut


54


is preferably molded of a suitable plastic material such as, for example, NYLON but can alternatively be formed of metal such as, for example steel. The illustrated drive nut


54


is generally “T-shaped” having a horizontally extending and tubular shaped top portion


88


and a vertically extending and tubular shaped bottom portion


89


downwardly extending from the center of the top portion


88


. The top portion


88


has an opening extending therethrough which is provided with threads for cooperation with the drive screw


50


. The threads can be unitary with the drive nut


54


or formed by an insert secured therein. The bottom portion


89


has a downward facing cavity forming a bearing surface


90


which is sized and shaped for cooperating with the drive nut attachment


56


to form a second self-aligning joint


92


, that is, to freely permit pivoting of the drive nut


54


relative to the drive nut attachment


56


about at least axes perpendicular to the rotational axis


64


. The illustrated second self-aligning joint


92


is a ball joint which permits pivoting of the drive nut


54


about every axis. The second self-aligning joint


92


automatically corrects misalignment of the drive nut


54


and/or drive screw


50


. The illustrated second self aligning joint


92


also forms a snap-fit connection between the drive nut


54


and the drive nut attachment


56


. The illustrated bearing surface


90


is generally frusto-spherically shaped. It is noted that the bearing surfaces


90


, and thus the second self-aligning joint


92


, can have other forms within the scope of the present invention.




The drive nut attachment


56


is sized and shaped for supporting the drive nut


54


and attaching the drive nut


54


to the lower arm


16


. The drive nut attachment


56


is preferably molded of a suitable plastic material such as, for example, NYLON but can alternatively be formed of metal such as, for example, steel. The drive nut attachment


56


includes a support portion


93


and an attachment portion


94


. The support portion


93


forms a bearing surface


96


for cooperation with the bearing surface


90


of the drive nut


54


as described above. The illustrated bearing surface


96


is a ball joint, that is, a generally frusto-spherically-shaped and is sized and shaped for receipt in the cavity of the drive nut


54


to engage the bearing surface


90


of the drive nut


54


. The attachment portion


94


is adapted for securing the support portion


93


to the guide


42


of the lower arm


16


. The illustrated attachment portion


96


is a generally cylindrically shaped protrusion which downwardly extends from the support portion


93


. The attachment portion


94


is sized and shaped to extend through openings in the lower arm guide


42


and the upper and lower bearing members


44


,


46


. A collar


98


is preferably provided to limit downward passage of the protrusion


96


through the openings. The protrusion of the attachment portion


94


can be held in position by for example, a cotter pin, spring clip, snap-in fingers or members, or any other suitable method.




As best shown in

FIGS. 1-4

, the electric motor


58


can be of any suitable type and can be secured to the firewall or other suitable location such as, for example, the mounting bracket of the control pedal


12




a


. The drive cable


60


is preferably a flexible cable and connects the motor


58


and the drive screw


50


so that rotation of the motor


58


rotates the drive screw


50


. It is noted that the drive screw


50


and the motor can be alternatively connected with a rigid connection. An input end of the drive cable


60


is connected to an output shaft of the motor


58


and an output end of the drive cable


60


is connected to the end of the drive screw


50


. It is noted that suitable gearing is provided between the motor


58


and the drive screw


50


as necessary depending on the requirements of the assembly


10


. It is also noted that the fixed portion or sheath of the drive cable


60


is rigidly secured to the forward end of the drive screw attachment


52


and a rotating portion or cable is operatively connected to the forward end of the drive screw


50


to rotate the drive screw


50


therewith.




As best shown in

FIGS. 1-6

, the illustrated drive assembly


18


also includes a cable support


100


for connecting the drive cable of the


60


of the second control pedal


12




b


to the rearward end of the drive screw


50


. Connecting or chaining the drive screws


50


with the electric motor


58


in series enables a single motor


58


to be utilized to adjust multiple control pedals


12




a


,


12




b


. It should be noted that additional control pedals


12




a


,


12




b


can be connected in this manner. It is also noted that if the control pedal assembly


10


has a single control pedal


12




a


, the drive screw


50


is the final control pedal


12




b


of the drive chain, or each control pedal


12




a


,


12




b


is driven by a separate motor


58


, the cable support


100


is not necessary.




As best shown in

FIGS. 5A and 6

, the cable support


100


has a attachment portion


102


, a support portion


104


, and a connecting portion


106


. The attachment portion


102


is generally tubular shaped and adapted to form a “snap fit connection” with the drive screw attachment


52


. The illustrated attachment portion is sized and shaped to snap over the rearward end of the drive screw attachment


52


at the first self-aligning joint


68


. The support portion


104


is generally tubular shaped and adapted to support the drive cable


60


at the rearward end of the drive screw


50


. The connecting portion


106


is sized and shaped to connect the attachment portion


102


and the support portion


104


such that the support portion


104


is supported by the attachment portion


102


in a cantilevered manner. The illustrated connecting portion


106


extends along the drive screw


50


at the lateral side opposite the upper arm to act as a shield or cover for the drive screw


50


. Configured in this manner, the drive cable


60


is supported without additional attachment to the upper arm


14


.




As best shown in

FIG. 7

, the control system


13


preferably includes a central processing unit (CPU) or controller


110


for activating the motor


58


, control switches


112


for inputting information from the driver to the controller


110


, and at least one sensor


114


for detecting motion of the control pedals


12




a


,


12




b


such as rotation of the drive screws


50


. The control system


13


forms a control loop wherein the controller


110


selectively sends signals to the motor


58


to activate and deactivate the motor


58


. When activated, the motor


58


rotates the drive screws


50


through the drive cables


60


. The sensor or sensors


14


detect movement of the control pedals


12




a


,


12




b


, such as rotations of the drive screws


50


, and sends signals to the controller


110


.




The controller


110


includes processing means and memory means which are adapted to control operation of the adjustable control pedal assembly


10


. The controller


110


is preferably in communication with a motor vehicle control unit


116


through a local bus


118


of the motor vehicle so that motor vehicle information can be supplied to or examined by the controller


110


and status of the control pedal assembly


10


can be supplied to or examined by the motor vehicle control unit


116


. It is noted that while the control system


13


of the illustrated embodiment utilizes a dedicated controller


110


, the controller


110


can alternatively be the motor vehicle control unit


116


or can be a controller of another system of the motor vehicle such as, for example, a keyless entry system or a powered seat system.




The control switches


112


are preferably push-button type switches but alternatively can be in many other forms such as, for example, toggle switches. The control switches


112


include at least a forward switch


120


which when activated sends control signals to move the control pedal


40


in a forward direction and a reverse or rearward switch


122


which when activated sends control signals to move the control pedal


40


in a rearward direction. Preferably, the control switches


112


include memory switches


124


,


126


which when activated return the control pedal


40


to preferred locations previously saved in memory of the controller


110


, a lock out switch


128


which when activated sends control signals preventing movement of the control pedal


40


, an override switch


130


which when activated permits the control pedal


40


to be moved by the driver in a desired manner regardless of existing conditions, and a memory save switch


132


which when activated sends a signal to save the current position of the control pedal


40


in memory of the controller


110


.




The sensor


114


is adapted to detect movement of the control pedal assembly


10


and send signals relating to such movement to the controller


110


. The sensor


114


is preferably located adjacent the drive screw


50


and adapted to detect rotations of the drive screw


50


. It is noted, however, that other sensors for detecting motion would be readily apparent to those skilled in the art such as, for example, a sensor for detecting rotational movement between upper and lower arms. The sensor


114


is preferably a Hall effect device mounted adjacent the drive screw


50


to directly sense each rotation of the drive screw


50


and to send a pulse or signal to the controller


110


for each revolution of the drive screw. Note that the pulses or signals can alternatively be for a portion of a rotation or for more than one rotation. The sensor


114


can alternately be another suitable non-contact sensor such as, for example, an inductance sensor, a potentiometer, an encoder, or the like. This rotational information obtained by sensor


114


is utilized by the controller


110


in many ways such as described hereinbelow.




The rotational information can be utilized to detect a failure in the control pedal assembly


10


. A failure in the control pedal assembly


10


is detected if signals (or lack thereof) from the sensor


114


to the controller


110


indicate that the drive screw


50


is not rotating, after the controller


110


has sent signals to activate the motor


58


. If the sensor


114


detects a control pedal assembly failure, the control pedal assembly


10


is preferably “shut down” to prevent any further activation of the motor


58


and possible damage to the control pedal assembly


10


. By directly sensing rotation of the drive screw


50


rather than at an intermediate point such as, for example, the shaft of the motor


58


, failure of any component of the control pedal assembly


10


is detected. Failures which are detected include failure of the motor


58


, failure of the sensor


104


, failure of the drive assembly


18


, and failure of the drive cable


60


. A visible warning instrument or audible alarm


134


, such as the illustrated LCD, is preferably provided so that a failure condition can be indicated to the driver.




The rotational information can additionally be utilized to automatically stop the drive nut


54


at ends of travel along the drive screw


50


. The controller


110


is adapted to stop the motor


58


when the rotational information indicates that the drive nut


54


has reached a predetermined end of travel along the drive screw


50


. The stop points are preprogrammed in the controller


110


. When the controller


110


receives signals from the sensor


104


indicating that the drive nut


54


has reached the predetermined stop points, the controller


110


stops the motor


58


and thus the movement of the drive nut


54


along the drive screw


50


. For example, the total travel of the pedal assembly


110


is defined by a predetermined number of sensor pulses and the controller


110


sends a stop signal to the motor


58


just prior to the pedal assembly


10


reaching the saved pulse number indicating a desired end of travel so that the pedal assembly


10


stops at the desired end of travel. Fore-aft movement of the lower arm


16


, therefore, is electronically stopped without engaging mechanical stops and resulting stress on the motor


58


and mechanical components. When a “hard stop” is engaged, the motor


58


stalls and current increases which may cause overheating of the motor


58


and a resulting shortened life of the motor


58


. It is noted, however, that the pedal assembly


10


is preferably provided with mechanical or “hard” stops for limiting travel of the drive nut


54


just beyond the “soft stops” for use in the event of a failure of the electronic or “soft” stops. In the illustrated embodiment, the hard stops include the ends of the slot


32


which form abutments which are engaged by the guide


42


at the end of travel along the slot to limit fore-aft movement of the lower arm


16


and axial movement of the drive nut


54


.




The rotational information can be further utilized to return the control pedal assembly


10


to a stored preferred location when selected by the driver. The driver adjusts the pedal assembly


10


to a preferred location and engages the memory save switch


132


so that the rotational information indicating the position of the drive nut


54


in the preferred location is saved in memory. At a later time, when the driver engages a memory switch


124


,


126


, the controller


110


automatically starts the motor


58


to rotate the drive screw


50


and move the drive nut


54


toward the saved position of the drive nut


54


. The controller


110


automatically stops the motor


58


when the rotational information (pulse count) from the sensor


114


indicates that the drive nut


54


has reached the saved position (saved pulse count) along the drive screw


50


.




The controller


110


is preferably adapted so that the pedal assembly


10


automatically moves forward to a predetermined location such as, for example, a full forward position under predetermined conditions. The predetermined conditions for moving the pedal assembly


10


forward are preferably the ignition key off and/or the door open. The pedal assembly


10


is then returned to the previous position or a memorized position once other predetermined conditions are met. The predetermined conditions for moving the pedal assembly


10


back to the previous position are preferably the ignition key on and/or the door closed. By moving the pedal assembly


10


to a forward position, the driver is able to more easily egress and/or ingress the motor vehicle.




The controller


110


is also preferably adapted so that the pedal assembly


10


cannot be adjusted under predetermined conditions. That is, the adjustment feature of the pedal assembly


10


is “locked-out” under certain conditions. The predetermined conditions which lock-out the pedal assembly


10


are preferably ignition key on, motor vehicle speed exceeds a predetermined speed, door is open, trunk is open, and/or driver's seat belt not fastened. Preferably, the driver can override the lock-out by engaging the override switch


130


and/or manually engage the lock-out when desired by engaging the lock out switch


128


.




Each control pedal


12




a


,


12




b


preferably includes a separate sensor


114


at the drive screw


50


so that rotation information is obtained regarding each of the drive screws


50


. By having rotation information regarding each drive screw


50


, the controller


110


can identify when the control pedals


12




a


,


12




b


, are not moving in the same manner. Preferably, the controller


110


sends a signal to stop the motor


58


if there is an indication that a predetermined relationship between two or more of the control pedals


12




a


,


12




b


is not maintained. For example, the predetermined relationship can be the step over of the brake and accelerator pedals. It is noted that alternatively, a single sensor


114


can be utilized which is located at the drive screw


50


at the end of the drive chain and/or separate motors


58


can be used for each of the control pedals


12




a


,


12




b


. It is also noted that while brake pedal is at the beginning of the chain and the accelerator pedal is at the end of the chain in the illustrated embodiment, the control pedals


12




a


,


12




b


can be connected in other arrangements.





FIG. 8

illustrates a control logic diagram of a preferred control system


13


using finite-state-machine theory. The states of the control pedal assembly


10


are stop, stall or motor failure, step over, sensor or drive mechanism failure, forward, reverse (rearward), memory


1


, and memory


2


. Each state can be defined in terms of the sensor output or the controller output to the motor (pedal positions and motor torque). At the stop state, T


e


=0 or<T


min


where T


e


is the motor output torque and T


min


is the minimum torque required to move the motor. At the stall or motor failure state, the condition is either T


c


≠0 and the event set is [T


e


=0 and Δ C


i


=0] where T


c


is the controller output signal to the motor which may be positive or negative, Δ C


i


represents an increment of pulse or the condition is T


c


≠0 and the event set is [ΔC


i


=0,i=1,2,3] where C


i


(i=1,2,3) is the pulse counting of each pedal. At the step over, sensor, or drive mechanism (including the drive screw) failure state, the condition is T


c


≠0 and T


e


≠0 and the condition set is either [ΔC


i


=0, ΔC


j


≠0, (i≠j)] or |C


i


-C


j


|>C


limit


(i≠j, i,j=1,2,3)] where C


limit


denotes a certain pulse limit, exceeding which a step over failure occurs. At the forward state, T


e


>0. At the reverse state T


e


<0. At the memory


1


state, T


e


=0, C


i


=C


mem1


, (i=1,2,3) where C


mem1


is the first memorized pulse count. At the memory


2


state, T


e


=0, C


i


=C


mem2


, (i=1,2,3) where C


mem2


is the second memorized pulse count. The switch signals are denoted as follows: F=1 indicates the forward switch is pushed or engaged; R=1 indicates the reverse switch is engaged or activated; M=1 indicates that the memory


1


switch is pushed or engaged; M=2 indicates that the memory


2


switch is pushed or engaged; L=1 indicates that the lock out switch is pushed or engaged; O=1 indicates that the override switch is pushed or engaged; I=1 indicates that the ignition key is on (this may also include or be replaced by D=1 which indicates the door is open); S=1 indicates save pulse count to memory; and FL=1 indicates the fault light or alarm is activated.




When the ignition key is on (I=1), the control pedals


12




a


,


12




b


automatically move to the previous memorized position and are ready to move. If the lock out feature is on (L=1), however, the control pedals


12




a


,


12




b


will remain in the present position and are unable to move until or unless the override switch


130


is engaged (O=1). Within the operation loop, there are three levels: a memory level wherein the control pedals


12




a


,


12




b


move to predefined positions stored in memory and stop; a moving level wherein the motor


58


will move the control pedals


12




a


,


12




b


forward and rearward depending of input signals from the switches


112


; and a fault or failure level wherein the system has problems and the alarm


134


is activated. In the move level, the driver can adjust the control pedals


12




a


,


12




b


forward or rearward, by engaging the forward and rearward switches (F=1, R=1)


120


,


122


respectively, until the control pedals


12




a


,


12




b


reach a desired position. The position of the control pedals


12




a


,


12




b


, that is the pulse count, is saved in memory if the save switch


132


is activated (s=1) or some predetermined conditions are satisfied such as, for example, one of the memory switches


124


,


126


are activated (M=1 or M=2) and no further movement occurs in a certain period of time. If a fault or failure is detected, the control pedals


12




a


,


12




b


are immediately stopped at the present position and the alarm


134


is activated (FL=1).




The electronic or “soft” stops can be implemented by establishing the number of pulses received from the sensor


114


over the desired stroke of the control pedals


12




a


,


12




b


(a total pulse count). Upper and lower pulse count limits (C


upper-limit


and C


lower-limit


) are established where the control pedal


12




a


,


12




b


can be stopped prior to engaging the mechanical or “hard” stops. For example, if the total pulse count is 130 where 130 is the far forward position and 0 is the far rearward position, the control pedal


12




a


,


12




b


can be operated between lower and upper pulse limits of about 5 and about 125 respectively.




From the foregoing disclosure and detailed description of certain preferred embodiments, it will be apparent that various modifications, additions and other alternative embodiments are possible without departing from the true scope and spirit of the present invention. For example, it will be apparent to those skilled in the art, given the benefit of the present disclosure, that the control pedal assembly can at least partly be operated from a remote control unit such as a keyless entry device. The embodiments discussed were chosen and described to provide the best illustration of the principles of the present invention and its practical application to thereby enable one of ordinary skill in the art to utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated. All such modifications and variations are within the scope of the present invention as determined by the appended claims when interpreted in accordance with the benefit to which they are fairly, legally, and equitably entitled.



Claims
  • 1. A control pedal comprising, in combination:a first support; a screw secured to the first support; a nut threadably engaging the screw and adapted to axially move along the screw upon rotation of the screw; a second support operatively connected to the nut for fore-aft movement of the second support relative to the first support upon axial movement of the nut along the screw; a sensor adjacent to one of the first support and second support; a motor operatively connected to the screw to selectively rotate the screw and axially move the nut along the screw; and a controller in communication with the motor and the sensor and adapted to automatically operate the motor to move the second support in a forward direction relative to the first support to a predetermined position when predetermined conditions are met; wherein the predetermined conditions includes at least one of an ignition switch turned off and an open door.
  • 2. The control pedal according to claim 1, wherein the predetermined position is a full forward position.
  • 3. The control pedal according to claim 2, wherein the predetermined conditions include both an ignition switch turned off and an open door.
  • 4. The control pedal according to claim 1, wherein the predetermined conditions include both an ignition switch turned off and an open door.
CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of patent application Ser. No. 09/492,636 filed Jan. 27, 2000 now U.S. Pat. No. 6,352,007.

US Referenced Citations (7)
Number Name Date Kind
4661752 Nishikawa et al. Apr 1987 A
4809180 Saitoh Feb 1989 A
5722302 Rixon et al. Mar 1998 A
5996438 Elton Dec 1999 A
6247381 Toelke et al. Jun 2001 B1
6293584 Levine Sep 2001 B1
6450061 Chapman et al. Sep 2002 B1
Continuations (1)
Number Date Country
Parent 09/492636 Jan 2000 US
Child 10/026499 US