Abstract:
A steering system disengages a wheel assembly of a vehicle in response to an event while driving. The steering system includes a suspension knuckle, a tie rod, and a puller. The puller includes a connector that removably engages the suspension knuckle and the tie rod to interconnect the suspension knuckle and the tie rod. The puller is operable to move the connector to disconnect the connector from at least one of the suspension knuckle and the tie rod in response to the event. The vehicle is operated along a longitudinal axis while driving and a moment of the vehicle about the longitudinal axis is sensed. If the moment exceeds the threshold, the puller is energized to disconnect the suspension knuckle from the tie rod.

Description:
TECHNICAL FIELD 
       [0001]    The present invention relates to a system for disengaging a wheel assembly of a vehicle and a method of doing the same. 
       BACKGROUND OF THE INVENTION 
       [0002]    A typical vehicle includes a steering system having a steering mechanism, a pair of tie rods, and a pair of suspension knuckles. The steering mechanism includes a body and a rack that extends through the body to opposing ends. The rack is movable with respect to body. One of the tie rods are pivotally attached to a selective end of the rack. Each of the tie rods extend from the end of the rack to a tie joint. A suspension knuckle is pivotally attached to a selective tie joint. Each suspension knuckle is attached to a wheel assembly. Each suspension knuckle turns the respective wheel assembly in response to the rack moving with respect to the body of the steering assembly to steer the vehicle. 
         [0003]    Each suspension knuckle includes a support member which is adapted to support one of the wheel assemblies. An upper and a lower support arm extend from the support member. A steering arm extends from the support member to a steering joint. The tie joint of the tie rod is connected to the steering joint of the steering arm to turn the wheel assemblies and steer the vehicle. An upper control arm is pivotally connected to the upper support arm and a lower control arm is pivotally connected to the lower support arm. The upper and lower control arms are also pivotally connected to a chassis of the vehicle. The pivotal connections between the upper and lower control arms and the respective suspension knuckles and the chassis allow the wheel assemblies to move up and down, relative to the chassis, while driving the vehicle. 
       SUMMARY OF THE INVENTION 
       [0004]    A steering system for a vehicle includes a suspension knuckle and a tie rod. A puller has a connector for engaging each of the suspension knuckle and the tie rod to interconnect the suspension knuckle and the tie rod when the connector is in an extended position. The connector is movable to a retracted position to disconnect the connector from at least one of the suspension knuckle and the tie rod in response to an event. 
         [0005]    A steering system for steering a vehicle while driving the vehicle includes a first and a second suspension knuckle and a steering mechanism. A first tie rod, for turning the first suspension knuckle, is disposed between the steering mechanism and the first suspension knuckle. A second tie rod, for turning the second suspension knuckle, is disposed between the steering mechanism and the second suspension knuckle. A first puller is configured for engaging the first suspension knuckle and the first tie rod to interconnect the first suspension knuckle and the first tie rod when the first puller is in a de-energized position. A second puller is configured for engaging the second suspension knuckle and the second tie rod to interconnect the second suspension knuckle and the second tie rod when the second puller is in a de-energized position. At least one of the pullers is movable from the de-energized position to an energized position in response to an event while driving the vehicle such that at least one of the pullers disconnects the suspension knuckle from the respective tie rod. 
         [0006]    A method of controlling a vehicle in response to an event while driving the vehicle includes operating the vehicle along a longitudinal axis while driving the vehicle. A moment of the vehicle about the longitudinal axis is sensed. One of a first and a second suspension knuckle is disconnected from a respective one of a first and second tie rod when the moment of the vehicle about the longitudinal axis is sensed to exceed a threshold. 
         [0007]    The above features and advantages and other features and advantages of the present invention are readily apparent from the following detailed description of the best modes for carrying out the invention when taken in connection with the accompanying drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0008]    Referring now to the figures, which are exemplary embodiments and wherein like elements are numbered alike: 
           [0009]      FIG. 1  is a perspective view of a steering system for a vehicle having pullers for removably connecting tie rods to suspension knuckles; 
           [0010]      FIG. 2  is a partial schematic perspective view of the puller in a de-energized position interconnecting a steering arm of one of the suspension knuckles to a tie joint of one of the tie rods; and 
           [0011]      FIG. 3  is a partial schematic perspective view of the puller of  FIG. 2  in an energized position disconnecting the steering arm from the tie joint. 
       
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0012]    Referring to the drawings, wherein like reference numbers refer to like components,  FIG. 1  shows a steering system  10  for steering a vehicle. The steering system  10  includes a steering assembly  12  and a first and second wheel assembly  22 ,  24 . 
         [0013]    The steering assembly  12  includes a steering mechanism  13  having a body  40  that extends between a first end  42  opposing a second end  44 . The steering assembly  12  also includes a rack (not shown) that extends through the body  40  between the opposing ends  42 ,  44 . The rack is movable back and forth within the body  40 . The steering assembly  12  also includes a first tie rod  14  that extends from the first end  42  and a second tie rod  16  that extends from the second end  44 . One of the tie rods  14 ,  16  is pivotally attached to a respective end  42 ,  44  of the rack of the mechanism  13 . The tie rods  14 ,  16  extend from the steering mechanism  13  in opposing directions, as shown in  FIG. 1 . The first tie rod  14  extends from the steering mechanism  13  to a first tie joint  48  and the second tie rod  16  extends from the steering mechanism  13  to a second tie joint  50 . 
         [0014]    The wheel assemblies  22 ,  24  include a first and a second suspension knuckle  18 ,  20 . As will be described in more detail below, the first tie joint  48  is operatively connected to the first suspension knuckle  18  and the second tie joint  50  is operatively connected to the second suspension knuckle  20 . Each wheel assembly  22 ,  24  also includes a rotor  26 , a wheel  28 , a tire  30 , a brake assembly  32 , and the like. However, the wheel assemblies  22 ,  24  may have more or less components as known to those skilled in the art. 
         [0015]    The steering assembly  12  is operatively connected to a steering wheel (not shown). Turning the steering wheel moves the rack back and forth relative to the body  40  such that the wheel assemblies  22 ,  24  of the vehicle turn in response to rotating the steering wheel. Therefore, referring to  FIG. 1 , when the steering wheel is turned in a first direction  34 , i.e., toward the left of the vehicle, both of the wheel assemblies  22 ,  24  also turn toward the left of the vehicle to turn the vehicle to the left as the vehicle is driving along a longitudinal axis  36 . Conversely, when the steering wheel is turned in a second direction  38 , i.e., toward the right of the vehicle, the wheel assemblies  22 ,  24  also turn toward the right of the vehicle to turn the vehicle to the right as the vehicle is driving along the longitudinal axis  36 . 
         [0016]    Each of the suspension knuckles  18 ,  20  include a support member  52  which is adapted to support the wheel  28  assembly. In one embodiment, an upper and a lower support arm  54 ,  56  extend from the support member  52  in spaced relationship to one another. A steering arm  58  extends from the support member  52 , between the support arms  54 ,  56 . The steering arm  58  extends to a steering joint  60 . The tie joint  48 ,  50  of the respective tie rod  14 ,  16  is disposed over, and is connected to, the steering joint  60  of the steering arm  58 . The connection between each of the tie joints  48 ,  50  and the respective steering joint  60  allows the wheel assemblies  22 ,  24  to turn in the first direction  34 , toward the left, or in the second direction  38 , toward the right, relative to the longitudinal axis  36 , to steer the vehicle in response to moving the tie rods  14 ,  16  back and forth. It should be appreciated, however, that suspension knuckles  18 ,  20  having other configurations known to those skilled in the art may also be used. 
         [0017]    An upper control arm  62  is pivotally connected to each of the upper support arms  54  and a lower control arm  64  is pivotally connected to each of the lower support arms  56 , as shown in  FIG. 1 . The upper and lower control arms  62 ,  64  are also pivotally connected to a chassis (not shown) of the vehicle. The pivotal connections between the upper and lower control arms  62 ,  64 , the respective first and second suspension knuckles  18 ,  20 , and the chassis allows each wheel assembly  22 ,  24  to move up and down, relative to the chassis, while driving the vehicle. 
         [0018]    Referring to  FIGS. 1-3 , a puller  66  operatively connects the tie joint  48 ,  50  of the tie rod  14 ,  16  to the steering joint  60  of the steering arm  58 . The puller  66  is movable between a de-energized position, as shown in  FIG. 2 , and an energized position, as shown in  FIG. 3 . In the de-energized position, the puller  66  interconnects the tie joint  48 ,  50  of the tie rod  14 ,  16  and the steering joint  60  of the steering arm  58 . In the energized position, the puller  66  is moved to disconnect the tie joint  48 ,  50  from steering joint  60 . A bracket  68  may extend from the puller  66  and connect the puller  66  to the respective suspension knuckle  18 ,  20 . It should be appreciated, however, that the puller  66  is not limited to extending from the suspension knuckles  18 ,  20 , but may extend from any other component of the vehicle as known to those skilled in the art. 
         [0019]    Referring to  FIGS. 2 and 3 , the puller  66  includes a connector  70 . The connector  70  may be a pin  76  that is movable linearly between an extended position, corresponding to the de-energized position shown in  FIG. 2 , and a retracted position, corresponding to the energized position shown in  FIG. 3 . In one embodiment, the tie joint  48 ,  50  defines a first hole  72  and the steering joint  60  defines a second hole  74  and the holes  72 ,  74  are aligned. The connector  70  extends through the first and second holes  72 ,  74  to interconnect the tie joint  48 ,  50  of the tie rod  14 ,  16  and the steering joint  60  of the steering arm  58  when the puller  66  is in the de-energized position, i.e., the extended position. Likewise, the connector  70  is removed from the first and second holes  72 ,  74  to disconnect the tie joint  48 ,  50  of the tie rod  14 ,  16  and the steering joint  60  of the steering arm  58  when the puller  66  is in the energized position, i.e., retracted position. It should be appreciated that the invention is not limited to having holes  72 ,  74  defined in each of the tie joint  48 ,  50  and the steering joint  60  as other configurations for connecting the tie rod  14 ,  16  to the steering arm  58  may be used as known to those skilled in the art. 
         [0020]    Referring again to  FIGS. 2 and 3 , the puller  66  also includes an actuator  78  that moves the connector  70  in response to the application of a signal to disconnect one of the tie rods  14 ,  16 , from the respective suspension knuckle  18 ,  20 . In one embodiment, the actuator  78  is electromagnetic. It should be appreciated, however, that the actuator  78  is not limited to being electromagnetic, but may be any type of actuator  78  known to those skilled in the art for moving the connector  70  in response to the signal to disconnect the tie rod  14 ,  16  from the respective suspension knuckle  18 ,  20 . This means that in the presence of the signal, the actuator  78  moves the connector  70  from the extended position to the retracted position to disconnect the tie rod  14 ,  16  from the respective suspension knuckle  18 ,  20 . In one embodiment, the vehicle includes a controller  80 . The controller  80  is operatively connected to each of the actuators  78  and the controller  80  sends the signal to the actuator  78  of the puller  66 . In response to the signal, the actuator  78  is energized to move the connector  70  to the retracted position and disconnect the tie joint  48 ,  50  of the tie rod  14 ,  16  from the steering joint  60  of the steering arm  58 . 
         [0021]    At least one sensor  82  may be disposed in the vehicle. The sensor  82 , which is operatively connected to the controller  80 , is for sensing a moment of the vehicle about the longitudinal axis  36  as the vehicle is driving along the longitudinal axis  36 . As the vehicle is driving along the longitudinal axis  36 , the vehicle may experience an event that results in a moment about the longitudinal axis  36 . The sensor  82  communicates the moment of the vehicle about the longitudinal axis  36  to the controller  80 . The controller  80  determines a direction of the moment of the vehicle about the longitudinal axis  36  as being either a first direction  34  of the moment, i.e., toward the left of the vehicle, or a second direction  38  of the moment of inertia, i.e., toward the right of the vehicle, opposite the first direction  34  of the moment of inertia. When the controller  80  determines from the sensor  82  that the direction of the moment is in the first direction  34  about the longitudinal axis  36  and is above a threshold amount or value, the controller  80  sends the signal to the first puller  66  to disconnect the first suspension knuckle  18  from the first tie rod  14  to reduce the moment of the vehicle about the longitudinal axis  36 . Likewise, when the sensor  82  senses that the direction of the moment is in the second direction  38  about the longitudinal axis  36  and is above the threshold amount, the controller  80  sends the signal to the second puller  66  to disconnect the second suspension knuckle  20  from the first tie rod  14  to reduce the moment of the vehicle about the longitudinal axis  36 . 
         [0022]    While the best modes for carrying out the invention have been described in detail, those familiar with the art to which this invention relates will recognize various alternative designs and embodiments for practicing the invention within the scope of the appended claims.