Abstract: A wind tunnel for measuring the aerodynamics of a vehicle may comprise a test section. Air moving through the test section may be collected in a plurality of individual ducts, each with a fan for moving the air through the test section and ducts. The vehicle or vehicle wheels may be supported at an incine.

Abstract: The parking brakes on a truck or other vehicle having plural axles are applied such that at least one wheel at a first end of a first axle receives a parking brake force without applying a parking brake force to any wheel at the opposite end of the first axle. In addition, at least one wheel at a second end of a second axle, the second end of the second axle being opposite to the first end of the first axle, receives a parking brake force. Desirably, any wheels at the opposite end of the second axle from the second end of the second axle are not the recipient of a parking brake force such that diagonally disposed parking brake forces are applied upon activation of the vehicle parking brakes. The first axle in one example is forwardly of the second axle and the first end of the first axle may be at the longitudinal side of the vehicle which is the heaviest.

Abstract: A wind tunnel for measuring the aerodynamics of a vehicle may comprise a test section. Air moving through the test section may be collected in a plurality of individual ducts, each with a fan for moving the air through the test section and ducts. The vehicle or vehicle wheels may be supported at an incine.

Abstract: The parking brakes on a truck or other vehicle having plural axles are applied such that at least one wheel at a first end of a first axle receives a parking brake force without applying a parking brake force to any wheel at the opposite end of the first axle. In addition, at least one wheel at a second end of a second axle, the second end of the second axle being opposite to the first end of the first axle, receives a parking brake force. Desirably, any wheels at the opposite end of the second axle from the second end of the second axle are not the recipient of a parking brake force such that diagonally disposed parking brake forces are applied upon activation of the vehicle parking brakes. The first axle in one example is forwardly of the second axle and the first end of the first axle may be at the longitudinal side of the vehicle which is the heaviest.

Abstract: A seat suspension system includes a vibration dampener adapted to operate over less than the full range over which a seat may be raised and lowered by a seat height adjuster, such as an air spring. The dampener may apply dampening forces which vary non-linearly, depending upon the extent a seat moves as a result of seat vibration. In several specific forms, the dampening mechanism is unlatched to permit relative movement of the seat and seat support mechanism relative to the dampener during seat height adjustment, with the dampener being relatched to again apply a dampening force. A mechanically simply seat leveling system may be employed to return the seat to a desired elevation in the event loading on the seat is varied, for example if a seat occupant gets up off a seat.

Abstract: A seat suspension method in one approach involves applying a dampening force over less than the full range over which a seat may be raised and lowered by a seat height adjuster. The step of applying a dampening force may comprise applying such a force which varies non-linearly, depending upon the extent a seat moves as a result of seat vibration. In several specific approaches, unlatching of the dampening mechanism may be accomplished to permit relative movement of the seat and seat support mechanism during seat height adjustment. Relatching of the vibration damper may be accomplished to again apply a dampening force. The seat may automatically be returned toward a desired elevation in the event loading on the seat is varied, for example if a seat occupant leaves the seat.

Abstract: The present invention relates to vehicle frame rails, preferably of steel, which are formed with a web section which is not of a constant thickness. Preferably, the frame rail is formed by roll forming to produce the variable thickness, although other techniques, such as machining, could be used.

Abstract: A stairway assembly is pivoted between deployed and stowed positions. The stairway in one form includes a sliding support from which the stairway is suspended at a location spaced from a stairway pivot. A link, which may be adjustable in length, couples the coupler to the stairway. A snubber is provided to limit vibration of the stairway when stowed. An actuator, which may comprise an electric motor, is positioned above and overlies a portion of a platform of the stairway. Extension and retraction of the actuator pivots the stairway between stowed and deployed positions.

Abstract: A seat support includes first and second link members coupling a seat supporting member to a base. The second link member has a first end portion pivoted to the base at a first pivot axis and a second end portion pivoted to the seat supporting member at a second pivot axis. The first link member has a first end portion pivoted to the base at a third pivot axis and a second end portion pivoted to the seat supporting member at a fourth pivot axis. The distance between the third and fourth pivot axes is greater than the distance between the first and second pivot axes and may be from about twelve percent to about twenty percent greater. The location of the pivot axes may be expressed by the formula L<(S+R−B). In this formula, L is the distance between the first and second pivot axes; S is the distance between the second and fourth pivot axes; R is the distance between the third and fourth pivot axes; and B is the distance between the first and third pivot axes.

Abstract: A method and apparatus involves selectively relieving the load from the rearmost wheels of a trailer to shorten the effective wheel base of the trailer. When the effective wheel base is shortened, off-tracking of the trailer during turning is reduced. The load may relieved while the trailer and vehicle are traveling at, for example, less than a first speed, with the vehicle turning at least at a first angle. The axle may be reloaded when the vehicle speed is increased to a second speed above the first speed and the vehicle is turning at an angle which is less than the first angle.

Abstract: An underhood air flow management system for a truck which includes cowl openings defined between cowl extensions and the rear edges of depending hood sections. Most preferably the cowl extension extends forwardly and inwardly toward the longitudinal centerline of the truck. The cowl extensions assist in deflecting air to the cowl openings, the air having passed through a radiator, along the sides of an engine and engine compartment, and through the cowl openings. The cowl openings preferably extend the full height of the depending hood sections. The bumper of the truck includes a lower extension. In addition, the front wheel wells of the truck are sealed at the front, partially sealed at the side and may be sealed at their rear to reduce the escape of air from the engine compartment through the front wheel wells. The cowl openings are preferably door-free and also lack air flow hindering severe transitions.

Abstract: A retractable stairway assembly for entering and exiting a vehicle with a cab has a stairway with steps. The stairway assembly is movable between a retracted position, in which the stairway is beneath the cab, and an extended position, in which the stairway is exposed to allow entering and exiting of the vehicle. The stairway assembly also has a panel that substantially hides the stairway when in the retracted position. An actuator moves the stairway assembly between the retracted and extended positions in response to closing and opening the door.

Abstract: A method of controlling a retractable stairway assembly for a vehicle includes monitoring at least one vehicle status condition such as (a) whether the vehicle is stopped, (b) whether the parking brake is set, (c) whether the cab is tilted in excess of a threshold, and (d) whether excess current is being required by a motor used to shift the stairway between stowed and deployed positions in the event an electric motor is used for this purpose. In the event any of these monitored conditions are not in a predetermined state, deployment of the stairway from a stowed position is blocked. Deployment and stowing of the stairway may also be interrupted depending upon vehicle status and other conditions. Interior and exterior vehicle alarms may be activated depending on vehicle status conditions and the mode of operation of the stairway.

Abstract: An electronic shift control lever assembly that transmits signal indicating a driver's desired gear selection to a variety of types of vehicle's transmissions in one form includes a steering column mounted shift lever. The shift lever is actuatable by the driver to signal a gear selection.