Abstract:
A throttle pedal assembly comprises a housing having a first and second side, top, bottom, front and back walls; a main chamber open to the front and bottom of the housing and a sensor cavity. A pedal assembly comprises a pedal, a pedal arm, and a head at an end of the pedal arm rotatable a pivot axis. A magnet is operatively connected to the pedal assembly to rotate on the pivot axis as the pedal assembly rotates about the pivot axis. A Hall effect sensor assembly mounted in the sensor cavity to be proximate the magnet yet separated from the magnet. The cavity and Hall effect sensor assembly are respectively shaped and sized such that the Hall chip and the magnet lay on a common axis such that the Hall chip and the magnet are coaxially aligned. The sensor cavity is sealed to prevent contaminants from entering the cavity.

Description:
RELATED APPLICATIONS 
       [0001]    This application claims priority to U.S. Pat. App. No. 62/030,923 which was filed on Jul. 30, 2014 and which is incorporated herein by reference. 
     
    
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
       [0002]    Not Applicable. 
       BACKGROUND OF THE INVENTION 
       [0003]    This application relates to throttle pedals, for example, for use with vehicles, and in particular to an improved throttle pedal that utilizes non-contact Hall effect technology. 
         [0004]    Hall effect sensors have been used in throttle pedals. However, such existing pedals have numerous parts, making them expensive and difficult to assemble. Further, during manufacture, these numerous parts can affect the correlation between the device rotation and the sensor output. 
       BRIEF SUMMARY OF THE INVENTION 
       [0005]    The throttle pedal disclosed has fewer moving parts relative to existing throttle pedals. This reduces the number of components required by the throttle device, thus making assembly of the throttle pedal easier. Additionally, it facilitates a closer correlation between device rotation and sensor output. This will provide for a more accurate indication of the position of the throttle pedal. 
     
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
         [0006]      FIG. 1  is a perspective view of the disclosed throttle pedal assembly; 
           [0007]      FIG. 2  is an exploded perspective view of the throttle pedal assembly; 
           [0008]      FIG. 3  is a vertical cross-section of the throttle pedal assembly taken along line  3 - 3  of  FIG. 1 ; 
           [0009]      FIG. 4  is a vertical cross-section of the throttle pedal assembly at 90° relative to  FIG. 3 , and taken along line  4 - 4  of  FIG. 1 ; 
           [0010]      FIG. 5  is a horizontal cross-sectional view of the throttle pedal assembly taken along line  5 - 5  of  FIG. 3   
           [0011]      FIG. 6  is a vertical cross-sectional view through the PC Board housing of the throttle pedal assembly, taken along line  6 - 6  of  FIG. 1 ; 
           [0012]      FIGS. 7 and 8  are front and back perspective views, respectively of the housing for the throttle pedal assembly; 
           [0013]      FIGS. 9 and 10  are cross-sectional views of the housing taken along lines  9 - 9  and  10 - 10 , respectively, of  FIG. 7 ; and 
           [0014]      FIG. 11  is a cross-sectional view of the housing taken along line  11 - 11  of  FIG. 10 . 
       
    
    
       [0015]    Corresponding reference numerals will be used throughout the several figures of the drawings. 
       DETAILED DESCRIPTION OF THE INVENTION 
       [0016]    The following detailed description illustrates the invention by way of example and not by way of limitation. This description will clearly enable one skilled in the art to make and use the claimed invention, and describes several embodiments, adaptations, variations, alternatives and uses of the claimed invention, including what I presently believe is the best mode of carrying out the claimed invention. Additionally, it is to be understood that the claimed invention is not limited in its application to the details of construction and the arrangements of components set forth in the following description or illustrated in the drawings. The claimed invention is capable of other embodiments and of being practiced or being carried out in various ways. Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. 
         [0017]    A throttle pedal assembly  10  is shown generally in  FIG. 1  and in an exploded view in  FIG. 2 . The throttle pedal assembly  10  comprises a housing  12  having a front wall  12   a , a rear wall  12   b , a right side wall  12   c , a left side wall  12   d , a top  12   e  and a bottom  12   f . A mounting plate or support bracket assembly  14  for mounting the throttle pedal assembly  10  in a vehicle extends from the edges of the rear surface  12   b , and, as seen, is effectively a continuation of the rear surface  12   b  of the housing. The manner of mounting the throttle pedal assembly is well known to those of ordinary skill in the art, and will not be described. The throttle pedal assembly, for example, may be affixed to an adaptor plate to facilitate mounting with various vehicle configurations. 
         [0018]    A pedal assembly  20  is pivotally mounted to the housing  12 . The pedal assembly  20  comprises a pedal  22  and a pedal arm  24  extending rearwardly from the pedal  22 . The pedal arm  24  ends in a head  26  that is remote from the pedal  22 . A spring bracket  28  extends upwardly from the pivot head  26  and includes a spring positioning button  28   a . The pedal assembly head  26  includes a passage  30  that extends the side-to-side width of the head  26 . The passage  30 , as seen in  3  and  7 , has generally straight or flat sidewalls joined by arced top and bottom walls, making the passage more or less of an elongated circle in cross-section. The passage  30  could be other shapes, such as polygonal, if desired. The passage  30  has at least one opening or depression  32 , and preferably two opposed openings or depressions, formed in the wall of the passage  30 . The openings  32  can be formed from a hole  32   a  extending radially through head  26 , with the hole  32   a  intersecting, and passing slightly beyond, the passage  30 . 
         [0019]    The housing  12  defines a chamber  40  which receives the head  26  of the pedal assembly  20 . The chamber  40  includes a lower portion  40   a  which opens to the front  12   a  wall and bottom  12   f  wall of the housing  12  and an upper portion  40   b  which opens to the back wall  12   b  of the housing. The housing lower portion  40   a  includes a back wall  41  comprising an upper curved portion  41   a  and a lower, more straight portion  41   b  which angles back slightly. The back wall  41  is below the opening of the chamber upper portion  40  to the back wall of the housing. As seen in  FIG. 3 , the back surface of the pedal assembly head  26  rides along the back wall upper surface  41   a . The chamber upper portion  40   b  includes an inner spring positioning member  42   a  and an outer spring positioning member  42   b  which are on the inner surface of the front wall  12   a . The housing  12  further includes an opening  44  in the right side wall  12   c  and a closed bore  46  in a left wall  48  of the chamber. The closed bore  46  is aligned with the right wall opening  44 . 
         [0020]    The pedal assembly  20  is mounted in the housing chamber  40  by means of a magnet carrier  50  to pivot between a normal raised position and a lowered pressed position, as seen in  FIG. 1 . The magnet carrier  50  includes a generally circular head  52  which is received in the housing right wall opening  44  and a body  54  which extends through the passage  30  of the pedal assembly head  26  into the closed bore  46  in the chamber wall  48 . The circular head  52  of the carrier  50  rides in the opening  44  (which is preferably circular) of the housing right side wall  12   b  to allow for the carrier to rotate relative to the housing. Preferably, the opening  44  is countersunk, as shown in  FIG. 6 , such that the outer surface of the carrier head is generally flush with the outer surface of the housing  12 . The carrier body  54  is shaped generally complimentarily to the pedal assembly head passage  30 . Hence, as seen in  FIGS. 2 and 3 , the magnet carrier body has a generally flat side wall. The corresponding shapes (flattened elongated circles) of the magnet carrier body  54  and the pedal head passage  30  rotationally fix the carrier  50  relative to the pedal head  26 . Thus, the magnet carrier  50  defines a pivot axle for the pedal assembly  20 . Movement of the pedal arm (such as by a driver stepping on or removing pressure from the pedal) translates to rotational motion of the magnet carrier. 
         [0021]    The magnet carrier  50  is also axially fixed to the pedal assembly head  26  to prevent axial movement of the magnet carrier relative to the pedal assembly head  26 . Because the pedal assembly head is generally axially fixed in the housing by the chamber  40 , the carrier is also axially fixed relative to the housing  12 . To axially fix the carrier  50  to the pedal assembly head  26 , the carrier includes opposed projections or nubs  56  which extend radially outwardly from the magnet carrier body  54 . The nubs  56  are sized and positioned to be received in the openings  32  in the head passage  30 . The nubs  56  engage the openings  32  to axially fix the position of the carrier to the pedal assembly head  26 . The nubs further rotationally fix the carrier  50  to the pedal assembly head  26 . The magnet carrier body (or shaft)  54  is preferably hollow, and the nubs  56  are formed on flexible or bendable arms  58  which can deflect inwardly. Thus, the pedal is rotationally mounted in the housing chamber  40  by first positioning the pedal assembly head  26  in the chamber  40  with the head bore  30  aligned with the right wall opening  44  and the closed hole  46  in the housing. The carrier  50  is then inserted through the right wall opening  44  and the head bore  30  until the nubs  56  engage the head bore openings  32 . As can be appreciated, the carrier arms  56  deflect inwardly to allow the carrier body  54  to pass through the pedal assembly head bore  30 . When the nubs  56  are aligned with bore openings  32 , the carrier arms snap back to their normal position. At that point, the carrier snaps into engagement with the pedal head. This snap connection allows for assembly of pedal assembly  20  to the housing  12  to be accomplished without the use of tools. 
         [0022]    An inner spring  62  and an outer spring  64  are positioned in the housing chamber upper portion  40   b . The two springs are coaxial with each other, and extend between the spring positioning members  42   a,b  on the chamber front wall and the spring positioning button  28   a  in the spring bracket  28  of the pedal assembly. The springs  62 ,  64  are, for example, torsion springs, which return the pedal to the normal, raised, position after the pedal has been released from the pressed position (i.e., after a driver lifts his or her foot off the pedal). Although two springs are shown, it will be appreciated that a single spring could be used if desired. Alternatively, a different biasing or spring material could be used which would return the pedal to its raised position after being released from a pressed position. The housing chamber  40  and the pedal assembly head  26  are sized and shaped such that the pedal can move along an arc of between about 15° to about 25°, and preferably between about 18° to about 22°. 
         [0023]    As best seen in  FIG. 5 , the carrier  50  has a magnet  60  mounted in the end of the magnet carrier body  54  opposite the carrier head  52 . The magnet carrier body  54  is sized such that the magnet  60  is proximate the inner surface of the closed bore  46 . Because the magnet  50  is mounted to the shaft  36 , the magnet  40  will rotate with the shaft as the pedal  22  is depressed. In a preferred embodiment, the magnet is molded into the magnet carrier body (which is made from a plastic). Alternatively, the magnet  50  can be glued or snapped into a depression formed at the end of the magnet carrier body. 
         [0024]    A sensor cavity  70  is formed in the left surface  12   d  of the housing. The cavity  70  opens to the top surface  12   e  of the housing. The housing includes a sleeve  71  extending upwardly from the top of the cavity  70 . A Hall effect sensor assembly or PC board  72  having a Hall chip  74  is received in the cavity  70 . As seen in  FIG. 6 , the closed bore  46  in the housing chamber  40  extends toward the sensor cavity  70 , but is separated from the sensor cavity by the end wall of the bore  46 . When mounted in the sensor cavity, the Hall chip  74  is located opposite, and in alignment with, the magnet  60 , and the two are separated only by the thin end wall of the closed bore  46 . Further, the cavity  70  is sized and positioned such that when the Hall effect sensor assembly  72  and the pedal assembly  20  are mounted in the housing, the Hall chip  74  and the magnet  60  will be on the same axis. That is, the Hall chip  74  and magnet  60  will be coaxial. 
         [0025]    The PC board  72  and the Hall effect chip  74  are encased in resin  78 . In a preferred method, the PC board with the Hall effect chip are first encapsulated in the resin, and then then the encapsulated PC board with the Hall effect chip is secured in the sensor cavity  70 , such as by heat staking the assembly in the cavity  70 . Alternatively, the resin could be molded around the PC board and the sensor cavity  70  could be shaped to enable the hall effect sensor assembly (encapsulated PC board with Hall effect sensor) to be snap fitted into the cavity. As a further alternative, the sensor assembly  72  can be positioned in the sensor cavity  70 , and then the sensor cavity can be filled with the resin  78  to surround and encapsulate the sensor assembly. The resin can be any settable resin which is not electrically conductive. The resin seals the sensor assembly and totally isolates the sensor assembly  72  from the environment, thereby preventing dirt, dust, water, etc. from contacting the sensor assembly  72 . Thus, dirt, dust, water, etc. cannot interfere or compromise the sensor signals. 
         [0026]    The sensor housing includes a connector sleeve  71 , as noted, which extends upwardly from the housing top  12   e . The sensor assembly include pins  78 A-F which extend up from the PC board into the sleeve  71 . The sleeve  71 , however, extends above the ends of the pins  78 A-F. The sleeve  71  is sized to accept a connector body which can connect to the pins  78 A-F. As is known, the connector body will connect the sensor assembly  72  to a controller by means of a wire (such as a ribbon wire). 
         [0027]    An illustrative pin layout is as follows: 
         [0000]                                            Pin   Function                           78A   APSI-Signal           78B   APSI-Return/Ground           78C   APSI-Supply           78D   APSI-Supply           78E   APSI-Return/Ground           78F   APSI-Signal                        
However, it will be appreciated that other pin layout configurations can be used. Further, more or fewer pins can be used, as may be dictated by either the controller or the sensor assembly board.
 
         [0028]    In the throttle pedal assembly  10 , the magnet  60  and the Hall chip  74  are positioned on the same axis; the magnet  60  is an integral part of the magnet carrier  50  which defines the pivot axis for the pedal assembly  20 ; and because the hall chip  74  is encapsulated by the resin, it is an integral part of the housing  12 . This design gives the throttle pedal assembly significant advantages. First of all, as noted above, the design of the carrier  50  makes assembly of the throttle pedal assembly simple, and allows for production of the throttle pedal assembly to be accomplished without the use of tools. Further, because the magnet  60  is fixed to (or embedded in) the carrier  50 , rather than being fixed to the housing, there are no moving components in the sensor cavity  70 . Thus, the sensor cavity  70  can effectively be filled with the sealant  78  (that is, the sealant  78  can occupy the space defined by the sensor cavity  70 ) to ensure against ingress of water and/or dust which can affect the functioning of the Hall chip assembly  72 . 
         [0029]    As can be appreciated, the throttle pedal assembly  10  is produced from a minimal number of parts and is easy to manufacture. To manufacture the throttle pedal assembly, the sensor assembly is fixed in the sensor cavity  70  of the housing  12 . The head  26  of the pedal assembly  20  is inserted into the chamber  40  of the housing  12 . With the pedal assembly head passage  30  aligned with the housing openings  44  and  45 , the magnet carrier  50  is inserted through the housing opening  44 , the pedal assembly passage  30 , and into the blind bore  46 . When the magnet carrier is inserted into the bore  30 , the arms  58  flex inwardly. When the carrier body nubs  56  engage the passage  32   a  in the pedal assembly head, the arms pop back out, and the nubs  56  are urged into the pedal assembly head bore  32   a  to lock the magnet carrier to the pedal assembly  20 . As best seen in  FIG. 5 , a portion of the housing wall  12   c  will be between the pedal assembly head  26  and the magnet carrier head  52 . Thus, the interconnection of the magnet carrier to the pedal assembly, and the portion of the housing between pedal assembly head  26  and the magnet carrier head  52  will prevent the pedal assembly  20  from separating from the housing. Thus, the snap connection of the magnet carrier to the pedal assembly also connects the pedal assembly to the housing. 
         [0030]    To further facilitate manufacturing of the throttle pedal assembly  10 , the main components, i.e., the housing  12 , the pedal assembly  20 , and the magnet carrier  50  can all be made (for example, by molding) from an appropriate plastic. 
         [0031]    As various changes could be made in the above constructions without departing from the scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense. 
         [0032]    In the illustrative embodiment, the magnet  60  is mounted to the carrier  50  which defines the pivot axle for the pedal. Thus, the magnet  60  is operatively connected to the pedal to rotate about the axis defined by the carrier  50  as the pedal is depressed. It could also be possible to mount the magnet  60  to the side of the pedal assembly head  26  proximate the Hall effect chip  74 . This would achieve the same desired result—elimination of moving parts in the sensor cavity to thereby allow for sealing of the sensor cavity, preferably with an encapsulating sealant. 
         [0033]    The snap connection of the magnet carrier  50  to the pedal assembly head  26  could be accomplished in other ways. Although the projection/nub  56  is formed on the carrier  50  to be received in a recess in the wall of the head passage  28 , the projection could be formed on the head passage wall and the shaft could be provided with a depression or opening in the arm  58  which then engages the projection. In other possible embodiments, the individual depressions  30  of the head passage could be replaced with a circumferential groove (which could alternatively be formed on the outer surface of the shaft  38 ). The projections  38  could remain as individual projections, or they could be formed by a circumferential ring. Although the head passage  30  and the carrier  50  are both shown as being generally elongated circles, the passage  30  and a carrier body  54  could be polygonal. These matching polygonal shapes of the head passage and the carrier body would further help rotationally fix the carrier and pedal head together. In this instance, the projection (or depression/groove) would be formed along the polygonal portion of the carrier. Additionally, the carrier and pedal head can be rotationally fixed together by means of axially extending splines which are received in axially extending grooves. The spline could be formed on either the outer surface of the shaft or the wall of the head passage  30 , and the splines would be formed on the other of the two. In a further alternative, the carrier could define a passage which extends through the carrier generally normal to the axis of the shaft, and the pedal assembly arm  24  could be inserted into this channel to rotationally fix the pedal assembly  20  and carrier  50  together. These examples are merely illustrative.