Steer-sensitive variable damper and method utilizing a ring valve

A system for controlling the compression and rebound action of a vehicular suspension spring with a variable hydraulic damper, the system comprising:

• (a) a reservoir tube;
• (b) a fluid-filled cylinder fixedly mounted within the reservoir tube and cooperating therewith to form a fluid reservoir;
• (c) base valve means mounted at one end of the cylinder for controlling fluid flow between the cylinder and the reservoir tube;
• (d) a piston slidably mounted in the cylinder for both reciprocable and rotary motions and dividing the interior of the cylinder into upper and lower chambers;
• (e) a piston rod rotatably connected at one end to the piston rod and extending from the reservoir tube;
• (f) means for rotating the cylinder along its axis in response to a steering input to the vehicle;
• (g) means for rotatably fixing the piston rod to the vehicle;
• (h) slit means provided in a portion of the inner cylinder in fluid communication with the lower chamber;
• and
• (i) control valving means establishing a variable flow from the lower chamber to the reservoir, the control valving means rotatably fixed to the piston, wherein the slit means is opened and closed by the relative rotation between the control valve means and the inner cylinder in response to a steering input to the vehicle.

A method for varying the damping force of a hydraulic damper in a vehicular suspension system as a vehicle is steered, the damper of the type having a fluid-filled cylinder divided into upper and lower chambers by a reciprocable piston slidably mounted in the cylinder, the cylinder cooperating with a reservoir tube to form a reservoir, the method comprising the steps of:

• (a) rotatably fixing the piston to the vehicle;
• (b) rotatably fixing the cylinder to a steerable wheel assembly;
• (c) providing slit means in the cylinder in fluid communication with the lower chamber;
• (d) rotatably fixing control valve means to the piston in the lower chamber adjacent the slit means;
• and
• (e) rotating the wheel assembly to selectively align the control valve means with the slit means, thereby varying fluid flow from the lower chamber to the reservoir.

A method for varying damping of a sprung vehicle in a suspension system, the method comprising the steps of:

• (a) installing a hydraulic damper between sprung and unsprung portions of a vehicle, the damper including a fluid-filled cylinder mounted in and rotatably fixed to a reservoir tube;
• (b) attaching the reservoir tube to a steerable wheel assembly;
• (c) dividing an interior of the cylinder into upper and lower chambers with a reciprocable and rotatable piston;
• (d) rotatably fixing the piston to a sprung portion of the vehicle;
• (e) restricting fluid flow through internal passage means in the piston with a piston valving assembly;
• (f) rotatably fixing base valve means to the cylinder for controlling fluid flow between the lower chamber and a reservoir;
• (g) forming slit means in the cylinder in communication with the lower chamber;
• and
• (h) rotatably fixing control valve means having openings to the piston in the lower chamber adjacent the slit means;
• and
• (i) rotating the wheel assembly to selectively align the openings of the control valve means with the slit means to vary fluid flow from the lower chamber to the reservoir.

A method of varying fluid flow in a steerable hydraulic damper of a vehicular suspension system, the method comprising the steps of:

• (a) providing a fluid-filled cylinder;
• (b) dividing an interior of the cylinder into first and second chambers with a piston slidably mounted in cylinder;
• (c) fixedly connecting a first end of a piston rod to the piston and fixedly connecting a second end of the piston rod to a vehicle;
• (d) restricting fluid flow through the piston between the first and second chambers with piston valving means;
• (e) forming slit means in the cylinder in fluid communication with the second chamber;
• (f) establishing a variable flow between the second chamber and a reservoir with control valve means rotatably fixed with respect to the piston;
• (g) rotating the cylinder as the vehicle is steered to selectively align the control valve means with the slit means to vary flow from the second chamber to the reservoir.

A method of using a hydraulic damper in a vehicular suspension system, the method comprising the steps of:

• (a) mounting the damper having a fluid-filled cylinder mounting a reciprocable piston between sprung and unsprung portions of a vehicle;
• (b) rotatably fixing the piston to the sprung portion of the vehicle;
• (c) rotatably fixing the cylinder to the unsprung portion of the vehicle;
• (d) providing first and second fluid chambers in the cylinder separated by the piston;
• (e) providing slit means in the cylinder in fluid communication with the second chamber;
• (f) restricting fluid flow between the second fluid chamber and a reservoir as the piston reciprocates with a base valve means rotatably fixed to the cylinder;
• (g) providing variable fluid flow between the second fluid chamber and the reservoir with slotted control valve means rotatably fixed to the piston;
• and
• (h) rotating the cylinder to selectively align the slotted control valve means with the slit means to provide variable damping from the damper.