Abstract:
A damper assembly with a bypass for a vehicle comprises a pressure cylinder with a piston and piston rod for limiting the flow rate of damping fluid as passes from a first to a second side of said piston. A bypass provides fluid pathway between the first and second sides of the piston separately from the flow rare limitation. In one aspect, the bypass is remotely controllable from a passenger compartment of the vehicle. In another aspect, the bypass is remotely controllable based upon one or more variable parameters associated with the vehicle.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims benefit of U.S. provisional patent application Ser. No. 61/296,826, filed Jan. 20, 2010, which is herein incorporated by reference in its entirety, and is also a continuation-in-part of U.S. patent application Ser. No. 12/684,072 filed Jan. 7, 2010, which claims benefit of U.S. provisional patent application No. 61/143,152, filed Jan. 7, 2009, both of which are also incorporated herein in their entirety. 
     
    
     BACKGROUND 
       [0002]    1. Field of the Invention 
         [0003]    Embodiments of the present invention generally relate to a damper assembly for a vehicle. More specifically, certain embodiments relate to a remotely operated bypass device used in conjunction with a vehicle damper. 
         [0004]    Vehicle suspension systems typically include a spring component or components and a dampening component or components. Typically, mechanical springs, like helical springs are used with some type of viscous fluid-based dampening mechanism and the two are mounted functionally in parallel. In some instances features of the damper or spring are user-adjustable. What is needed is an improved method and apparatus for adjusting dampening characteristics, including remote adjustment. 
       SUMMARY OF THE INVENTION 
       [0005]    The present invention may be used with a damper assembly having a bypass. In one aspect, the assembly comprises a cylinder with a piston and piston rod for limiting the flow rate of damping fluid as it passes from a first to a second portion of said cylinder. A bypass provides fluid pathway between the first and second portions of the cylinder and may be independent of, or in conjunction with, the aforementioned flow rate limitation. In one aspect, the bypass is remotely controllable from a passenger compartment of the vehicle. In another aspect, the bypass is remotely controllable based upon one or more variable parameters associated with the vehicle. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0006]    So that the manner in which the above recited features can be understood in detail, a more particular description may be had by reference to embodiments, some of which are illustrated in the appended drawings. It is to be noted, however, that the appended drawings illustrate only typical embodiments of this invention and are therefore not to be considered limiting of its scope, for the invention may admit to other equally effective embodiments. 
           [0007]      FIG. 1  is a section view showing a suspension damping unit with a remotely operable bypass. 
           [0008]      FIG. 2  is an enlarged section view showing the remotely operable valve of the bypass in the open position. 
           [0009]      FIG. 3  is a section view showing the valve of  FIG. 2  in a closed position. 
           [0010]      FIG. 4  is a section view showing the valve of  FIG. 2  in a locked-out position. 
           [0011]      FIG. 5  is a schematic diagram showing a control arrangement for a remotely operated bypass. 
           [0012]      FIG. 6  is a schematic diagram showing another control arrangement for a remotely operated bypass. 
           [0013]      FIG. 7  is a graph showing some operational characteristics of the arrangement of  FIG. 4 . 
       
    
    
     DETAILED DESCRIPTION 
       [0014]    As used herein, the terms “down” “up” “downward” “upward” “lower” “upper” and other directional references are relative and are used for reference only.  FIG. 1  is a section view of a suspension damping unit  100 . The damper includes a cylinder portion  102  with a rod  107  and a piston  105 . Typically, the fluid meters from one side of the piston  105  to the other side by passing through flow paths  110 ,  112  formed in the piston  105 . In the embodiment shown, shims  115 ,  116  are used to partially obstruct the flow paths  110 ,  112  in each direction. By selecting shims  115 ,  116  having certain desired stiffness characteristics, the dampening effects caused by the piston  105  can be increased or decreased and dampening rates can be different between the compression and rebound strokes of the piston  105 . For example, shims  115  are configured to meter rebound flow from the rebound portion  103  of the cylinder  102  to the compression portion  104  of the cylinder  102 . Shims  116 , on the other hand, are configured to meter compression flow from the compression portion of the cylinder to the rebound portion. In one embodiment, shims  116  are not included on the rebound portion side, nor is there a compression flow path such as path  112 , leaving the piston essentially “locked out” in the compression stroke without some means of flow bypass. Note that piston apertures (not shown) may be included in planes other than those shown (e.g. other than apertures used by paths  110  and  112 ) and further that such apertures may, or may not, be subject to the shims  115 ,  116  as shown (because for example, the shims  115 ,  116  may be clover-shaped or have some other non-circular shape). 
         [0015]    A reservoir  125  is in fluid communication with the damper cylinder  102  for receiving and supplying damping fluid as the piston rod  107  moves in and out of the cylinder  102 . The reservoir includes a cylinder portion  128  in fluid communication with a rebound portion  103  of the damper cylinder  102  via fluid conduit  129 . The reservoir also includes a floating piston  130  with a volume of gas on a backside  131  (“blind end” side) of it, the gas being compressible as the reservoir cylinder  128 , on the “frontside”  132  fills with damping fluid due to movement of the damper rod  107  and piston  105  into the damper cylinder  102 . Certain features of reservoir type dampers are shown and described in U.S. Pat. No. 7,374,028, which is incorporated herein, in its entirety, by reference. The upper portion of the rod  107  is supplied with a bushing set  109  for connecting to a portion of a vehicle wheel suspension linkage. In another embodiment, not shown, the upper portion of the rod  107  (opposite the piston) may be supplied with an eyelet to be mounted to one part of the vehicle, while the lower part of the housing shown with an eyelet  108  is attached to another portion of the vehicle, such as the frame, that moves independently of the first part. A spring member (not shown) is usually mounted to act between the same portions of the vehicle as the damper. As the rod  107  and piston  105  move into cylinder  102  (during compression), the damping fluid slows the movement of the two portions of the vehicle relative to each other due to the incompressible fluid moving through the shimmed paths  112  (past shims  116 ) provided in the piston  105  and/or through a metered bypass  150 , as will be described herein. As the rod  107  and piston  105  move out of the cylinder  102  (during extension or “rebound”) fluid meters again through shimmed paths  110  and the flow rate and corresponding rebound rate is controlled by the shims  115 . 
         [0016]    In  FIG. 1 , the piston is shown at full extension and moving downward in a compression stroke, the movement shown by arrow  157 . A bypass  150  includes a tubular body  155  that communicates with the damper cylinder  102  through entry  160  and exit  165  pathways. The bypass assembly  150  permits damping fluid to travel from a first side of the piston  105  to the other side without traversing shimmed flow paths  110 ,  112  that may otherwise be traversed in a compression stroke of the damper. In  FIG. 1 , the bypass  150  is shown in an “open” position with the flow of fluid through the bypass shown by arrows  156  from a compression side to a rebound side of the piston  105 . In the embodiment of  FIG. 1 , the bypass includes a remotely controllable, needle-type check valve/throttle valve  200 , located proximate an exit pathway  165  allowing flow in direction  156  and checking flow in opposite direction. 
         [0017]    The entry pathway  160  to the bypass  150  in the embodiment shown in  FIG. 1 , is located towards a lower end of the damper cylinder  102 . In one embodiment, as selected by design, the bypass will not operate after the piston  105  passes the entry pathway  160  near the end of a compression stroke. This “position sensitive” feature ensures increased dampening will be in effect near the end of the compression stoke to help prevent the piston from approaching a “bottomed out” position (e.g. impact) in the cylinder  102 . In some instances, multiple bypasses are used with a single damper and the entry pathways for each may be staggered axially along the length of the damper cylinder in order to provide an ever-increasing amount of dampening (and less bypass) as the piston moves through its compression stroke and towards the bottom of the damping cylinder. Each bypass may include some or all of the features described herein. Certain bypass damper features are described and shown in U.S. Pat. Nos. 6,296,092 and 6,415,895, each of which are incorporated herein, in its entirety, by reference. Additionally, the bypass and valve of the present embodiments can be used in any combination with the bypass valves shown and described in co-pending U.S. patent application Ser. No. 12/684,072. 
         [0018]      FIGS. 2 ,  3  and  4  are enlarged views showing the remotely operable needle valve  200  in various positions. In  FIG. 2 , the valve is in a damping-open position (fluid path shown by arrow  201 ) permitting the bypass to operate in a compression stroke of the damper  100 . The valve includes a valve body  204  housing a movable piston  205  which is sealed within the body. Three fluid communication points are provided in the body including an inlet  202  and outlet  203  for fluid passing through the valve  200  as well as an inlet  225  for control fluid as will be described herein. Extending from a first end of the piston  205  is a shaft  210  having a cone-shaped member  212  (other shapes such as spherical or flat, with corresponding seats, will also work suitably well) disposed on an end thereof. The cone-shaped member  212  is telescopically mounted relative to, and movable on, the shaft  210  and is biased in an extended position ( FIG. 3 ) due to a spring  215  coaxially mounted on the shaft  210  between the member  212  and the piston  205 . Due to the spring biasing, the cone-shaped member  212  normally seats itself against a seat  217  formed in an interior of the body  204 . In the damping open position shown however, fluid flow through the bypass has provided adequate force on the member  212  to urge it backwards, at least partially loading the spring  215  and creating fluid path  201  from the bypass into a rebound area of the damper cylinder as shown in  FIG. 1 . The characteristics of the spring  215  are typically chosen to permit the valve  200  (e.g. member  212 ) to open at a predetermined bypass pressure, with a predetermined amount of control pressure applied to inlet  225 , during a compression stroke of the damper  100 . For a given spring  215 , higher control pressure at inlet  225  will result in higher bypass pressure required to open the valve  200  and correspondingly higher damping resistance in the bypass  150  (more compression damping due to that bypass). In one embodiment, the valve is open in both directions when the valve member  205  is “topped out” against valve body  204 . In another embodiment however, when the valve piston  205  is abutted or “topped out” against valve body  204  the spring and relative dimensions of the valve  200  still allow for the cone member to engage the valve seat thereby closing the valve. In such embodiment backflow from the rebound side of the cylinder  102  to the compression side is always substantially closed and cracking pressure from flow along path  156  is determined by the pre-compression in the spring. In such embodiment, additional fluid pressure may be added to the inlet through port  225  to increase the cracking pressure for flow along path  156  and thereby increase compression damping through the bypass over that value provided by the spring compression “topped out.” It is generally noteworthy that while the descriptions herein often relate to compression damping bypass and rebound shut off, some or all of the bypass channels (or channel) on a given suspension unit may be configured to allow rebound damping bypass and shut off or impede compression damping bypass. 
         [0019]      FIG. 3  shows the valve  200  in a closed position (which it assumes during a rebound stroke of the damper). As shown, the cone shaped member  212  is seated against seat  217  due to the force of the spring  215  and absent an opposite force from fluid entering the valve along path  156  from the bypass. As member  212  telescopes out, a gap  220  is formed between the end of the shaft  210  and an interior of member  212 . A vent  221  is provided to relieve any pressure formed in the gap. With the fluid path  201  closed, fluid communication is substantially shut off from the rebound side of the cylinder into the valve body (and hence through the bypass back to the compression side is closed) and its “dead-end” path is shown by arrow  219 . 
         [0020]    Inlet  225  is formed in the valve body  204  for operation of the valve. In one embodiment inlet  225  may be pressurized to shift the valve to a third or “locked-out” position. In  FIG. 4 , the valve  200  is shown in the locked-out position, thereby preventing fluid flow through the bypass in either direction regardless of compression or rebound stroke. In the embodiment shown, the control inlet  225  provides a fluid path  230  to a piston surface  227  formed on an end of the piston  205 , opposite the cone-shaped member  212 . Specifically, activating pressure is introduced via inlet  225  to move the piston  205  and with it, member  212  toward seat  217 . Sufficient activating pressure fully compresses the spring  215  (substantial stack out) and/or closes the gap  220  thereby closing the cone  212  against the seat, sealing the bypass to both compression flow and rebound flow. In the embodiment shown, the valve  200  can be shifted to the third, locked-out position from either the first, open position or the second, closed position. Note that, when in the “locked out” position, the valve as shown will open to compression flow along path  156  when the compression flow pressure acting over the surface area of the seated valve cone  212  exceeds the inlet  225  pressure acting over the surface area of the piston  205 . Such inlet  225  pressure may be selected to correspond therefore to a desired compression overpressure relief value or “blow off” value thereby allowing compression bypass under “extreme” conditions even when the bypass is “locked out”. 
         [0021]    In the embodiment illustrated, the valve  200  is intended to be shifted to the locked-out position with control fluid acting upon piston  205 . In one embodiment, the activating pressure via inlet  225  is adjusted so that the valve  200  is closed to rebound fluid (with the cone-shaped member  212  in seat  217 ) but with the spring  215  not fully compressed or stacked out. In such a position, a high enough compression force (e.g. compression flow) will still open the valve  200  and allow fluid to pass through the valve in a compression stroke. In one arrangement, the activating pressure, controlled remotely, may be adjusted between levels where the lock-out is not energized and levels where the lock-out is fully energized. The activating pressure may also be adjusted at intermediate levels to create more or less damping resistance through the bypass. The activating pressure may be created by hydraulic or pneumatic input or any other suitable pressure source. 
         [0022]    In one example, the valve  200  is moved to a locked-out position and the bypass feature disabled by remote control from a simple operator-actuated switch located in the passenger compartment of the vehicle. In one embodiment, fluid pressure for controlling (e.g. locking-out) the valve  200  is provided by the vehicle&#39;s on-board source of pressurized hydraulic fluid created by, for example, the vehicle power steering system. In one embodiment, pneumatic pressure is used to control (e.g. close) the valve  200  where the pneumatic pressure is generated by an on-board compressor and accumulator system and conducted to the valve via a fluid conduit. In one embodiment, a linear electric motor (e.g. solenoid), or other suitable electric actuator, is used, in lieu of the aforementioned inlet  225  pressure, to move the “piston” axially within valve body. A shaft of the electric actuator (not shown) may be fixed to the piston such that axial movement of the shaft causes axial movement of the piston which in turn causes movement of the cone  212  (and compression of the spring as appropriate). In one embodiment, the electric actuator is configured to “push” the piston towards a closed position and to “pull” the piston away from the closed position depending on the direction of the current switched through the actuator. 
         [0023]      FIG. 5  is a schematic diagram illustrating a sample circuit  400  used to provide remote control of a bypass valve using a vehicle&#39;s power steering fluid (although any suitable fluid pressure source may be substituted for reservoir  410  as could be an electrical current source in the case of an electrically actuated valve  200 ). As illustrated, a fluid pathway  405  having a switch-operated valve (and/or pressure regulator)  402  therein runs from a fluid (or current) reservoir  410  that is kept pressurized by, in one embodiment, a power steering pump (not shown) to a bypass valve  200  that is operable, for example, by a user selectable dash board switch  415 . The valve  402  permits fluid to travel to the bypass valve  200 , thereby urging it to a closed position. When the switch  415  is in the “off” position, working pressure within the damper, and/or a biasing member such as a spring or annular atmospheric chamber (not shown), returns the bypass to its normally-open position (with or without residual spring compression as designed). Hydraulically actuated valving for use with additional components is shown and described in U.S. Pat. No. 6,073,536 and that patent is incorporated by reference herein in its entirety. 
         [0024]    While  FIG. 5  is simplified and involves control of a single bypass valve, it will be understood that the valve  402  could be plumbed to simultaneously or selectively (e.g. multi-position valve) provide a signal to two or more (e.g. four) bypass valves operable with two or more vehicle dampers and/or with a single damper having multiple bypass channels and multiple corresponding valves (e.g.  200 ) (or multiple dampers having multiple bypass channels). Additional switches could permit individual operation of separate damper bypass valves in individual bypass channels, whether on separate dampers or on the same multiple bypass damper, depending upon an operator&#39;s needs. While the example of  FIG. 5  uses fluid power for operating the bypass valve, a variety of means are available for remotely controlling a valve. For instance, a source of electrical power from a 12 volt battery could be used to operate a solenoid member, thereby shifting a piston in bypass valve  200  between open and closed positions. The valve or solenoid operating signal can be either via a physical conductor or an RF signal (or other wireless such as Bluetooth, WiFi, ANT) from a transmitter operated by the switch  415  to a receiver operable on the bypass valve  200  (which would derive power from the vehicle power system such as 12 volt). 
         [0025]    A remotely operable bypass like the one described above is particularly useful with an on/off road vehicle. These vehicles can have as much as 20″ of shock absorber travel to permit them to negotiate rough, uneven terrain at speed with usable shock absorbing function. In off-road applications, compliant dampening is necessary as the vehicle relies on its long travel suspension when encountering often large off-road obstacles. Operating a vehicle with very compliant, long travel suspension on a smooth road at higher speeds can be problematic due to the springiness/sponginess of the suspension and corresponding vehicle handling problems associated with that (e.g. turning roll, braking pitch). Such compliance can cause reduced handling characteristics and even loss of control. Such control issues can be pronounced when cornering at high speed as a compliant, long travel vehicle may tend to roll excessively. Similarly, such a vehicle may pitch and yaw excessively during braking and acceleration. With the remotely operated bypass dampening and “lock out” described herein, dampening characteristics of a shock absorber can be completely changed from a compliantly dampened “springy” arrangement to a highly dampened and “stiffer” (or fully locked out) system ideal for higher speeds on a smooth road. In one embodiment where compression flow through the piston is completely blocked, closure of the bypass  150  results in substantial “lock out” of the suspension (the suspension is rendered essentially rigid). In one embodiment where some compression flow is allowed through the piston (e.g. port  112  and shims  116 ), closure of the bypass  150  (closure of valve  200 ) results in a stiffer but still functional compression damper. In one embodiment, the shims  116  are sized, to optimize damping when the bypass  150  is open and when bypass  150  is closed based on total anticipated driving conditions. In one embodiment the bypass valve  200  is closed but may be opened at a predetermined compression flow pressure resulting in fairly stiff handling but maintaining an ability for the vehicle to absorb relatively large bumps. In one embodiment a bypass channel having an opening  160  located axially toward an upward (or “rebound” end) end of cylinder  102  remains wide open while other bypass channels having corresponding openings  160  located axially more toward the compression end of cylinder  102  are closed or highly restricted. Such would result in a suspension that would readily absorb small amplitude compressions (smooth highway ride) but would resist large compression deflections of low force magnitude (as during heavy cornering or braking) and would absorb large deflections of high force magnitude. A vehicle so configured would ride well on pavement (smooth surface), would absorb large unexpected bumps and would generally not wallow when cornering or braking. 
         [0026]    In addition to, or in lieu of, the simple, switch operated remote arrangement of  FIG. 5 , the remote bypass can be operated automatically based upon one or more driving conditions.  FIG. 6  shows a schematic diagram of a remote control system  500  based upon any or all of vehicle speed, damper rod speed, and damper rod position. One embodiment of  FIG. 6  is designed to automatically increase dampening in a shock absorber in the event a damper rod reaches a certain velocity in its travel towards the bottom end of a damper at a predetermined speed of the vehicle. In one embodiment the system adds dampening (and control) in the event of rapid operation (e.g. high rod velocity) of the damper to avoid a bottoming out of the damper rod as well as a loss of control that can accompany rapid compression of a shock absorber with a relative long amount of travel. In one embodiment the system adds dampening (e.g. closes or throttles down the bypass) in the event that the rod velocity in compression is relatively low, but the rod progresses past a certain point in the travel. Such configuration aids in stabilizing the vehicle against excessive low rate suspension movement events such as cornering roll, braking and acceleration yaw and pitch and “g-out.” 
         [0027]      FIG. 6  illustrates, for example, a system including three variables: rod speed, rod position and vehicle speed. Any or all of the variables shown may be considered by processor  502  in controlling the valve  200 . Any other suitable vehicle operation variable may be used in addition to or in lieu of the variables  515 ,  505 ,  510  such as for example piton rod compression strain, eyelet strain, vehicle mounted accelerometer (or tilt/inclinometer) data or any other suitable vehicle or component performance data. In one embodiment piston  105  position within cylinder  102  is determined using an accelerometer to sense modal resonance of cylinder  102 . Such resonance will change depending on the position of the piston  105  and an on-board processor (computer) is calibrated to correlate resonance with axial position. In one embodiment, a suitable proximity sensor or linear coil transducer or other electro-magnetic transducer is incorporated in the dampening cylinder to provide a sensor to monitor the position and/or speed of the piston (and suitable magnetic tag) with respect to the cylinder. In one embodiment, the magnetic transducer includes a waveguide and a magnet, such as a doughnut (toroidal) magnet that is joined to the cylinder and oriented such that the magnetic field generated by the magnet passes through the piston rod and the waveguide. Electric pulses are applied to the waveguide from a pulse generator that provides a stream of electric pulses, each of which is also provided to a signal processing circuit for timing purposes. When the electric pulse is applied to the waveguide a magnetic field is formed surrounding the waveguide. Interaction of this field with the magnetic field from the magnet causes a torsional strain wave pulse to be launched in the waveguide in both directions away from the magnet. A coil assembly and sensing tape is joined to the waveguide. The strain wave causes a dynamic effect in the permeability of the sensing tape which is biased with a permanent magnetic field by the magnet. The dynamic effect in the magnetic field of the coil assembly due to the strain wave pulse, results in an output signal from the coil assembly that is provided to the signal processing circuit along signal lines. By comparing the time of application of a particular electric pulse and a time of return of a sonic torsional strain wave pulse back along the waveguide, the signal processing circuit can calculate a distance of the magnet from the coil assembly or the relative velocity between the waveguide and the magnet. The signal processing circuit provides an output signal, either digital, or analog, proportional to the calculated distance and/or velocity. A transducer-operated arrangement for measuring rod speed and velocity is described in U.S. Pat. No. 5,952,823 and that patent is incorporated by reference herein in its entirety. 
         [0028]    While a transducer assembly located at the damper measures rod speed and location, a separate wheel speed transducer for sensing the rotational speed of a wheel about an axle includes housing fixed to the axle and containing therein, for example, two permanent magnets. In one embodiment the magnets are arranged such that an elongated pole piece commonly abuts first surfaces of each of the magnets, such surfaces being of like polarity. Two inductive coils having flux-conductive cores axially passing therethrough abut each of the magnets on second surfaces thereof, the second surfaces of the magnets again being of like polarity with respect to each other and of opposite polarity with respect to the first surfaces. Wheel speed transducers are described in U.S. Pat. No. 3,986,118 which is incorporated herein by reference in its entirety. 
         [0029]    In one embodiment, as illustrated in  FIG. 6 , a logic unit  502  with user-definable settings receives inputs from the rod speed  510  and location  505  transducers as well as the wheel speed transducer  515 . The logic unit is user-programmable and depending on the needs of the operator, the unit records the variables and then if certain criteria are met, the logic circuit sends its own signal to the bypass to either close or open (or optionally throttle) the bypass valve  200 . Thereafter, the condition of the bypass valve is relayed back to the logic unit  502 . 
         [0030]      FIG. 7  is a graph that illustrates a possible operation of one embodiment of the bypass assembly  500  of  FIG. 6 . The graph assumes a constant vehicle speed. For a given vehicle speed, rod position is shown on a y axis and rod velocity is shown on an x axis. The graph illustrates the possible on/off conditions of the bypass at combinations of relative rod position and relative rod velocity. For example, it may be desired that the bypass is operable (bypass “on”) unless the rod is near its compressed position and/or the rod velocity is relatively high (such as is exemplified in  FIG. 7 ). The on/off configurations of  FIG. 7  are by way of example only and any other suitable on/off logic based on the variable shown or other suitable variables may be used. In one embodiment it is desirable that the damper become relatively stiff at relatively low rod velocities and low rod compressive strain (corresponding for example to vehicle roll, pitch or yaw) but remains compliant in other positions. In one embodiment the piston rod  107  includes a “blow off” (overpressure relief valve typically allowing overpressure flow from the compression side to the rebound side) valve positioned in a channel coaxially disposed though the rod  107  and communicating one side of the piston (and cylinder) with the other side of the piston (and cylinder) independently of the apertures  110 , 112  and the bypass  150 . 
         [0031]    In one embodiment, the logic shown in  FIG. 6  assumes a single damper but the logic circuit is usable with any number of dampers or groups of dampers. For instance, the dampers on one side of the vehicle can be acted upon while the vehicles other dampers remain unaffected. 
         [0032]    While the examples illustrated relate to manual operation and automated operation based upon specific parameters, the remotely operated bypass can be used in a variety of ways with many different driving and road variables. In one example, the bypass is controlled based upon vehicle speed in conjunction with the angular location of the vehicle&#39;s steering wheel. In this manner, by sensing the steering wheel turn severity (angle of rotation), additional dampening can be applied to one damper or one set of dampers on one side of the vehicle (suitable for example to mitigate cornering roll) in the event of a sharp turn at a relatively high speed. In another example, a transducer, such as an accelerometer measures other aspects of the vehicle&#39;s suspension system, like axle force and/or moments applied to various parts of the vehicle, like steering tie rods, and directs change to the bypass valve positioning in response thereto. In another example, the bypass can be controlled at least in part by a pressure transducer measuring pressure in a vehicle tire and adding dampening characteristics to some or all of the wheels in the event of, for example, an increased or decreased pressure reading. In one embodiment the damper bypass or bypasses are controlled in response to braking pressure (as measured for example by a brake pedal sensor or brake fluid pressure sensor or accelerometer) In still another example, a parameter might include a gyroscopic mechanism that monitors vehicle trajectory and identifies a “spin-out” or other loss of control condition and adds and/or reduces dampening to some or all of the vehicle&#39;s dampers in the event of a loss of control to help the operator of the vehicle to regain control. 
         [0033]    While the foregoing is directed to embodiments of the present invention, other and further embodiments of the invention may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow.